diff --git a/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Constants.java b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Constants.java
new file mode 100644
index 0000000000..b646c686b2
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Constants.java
@@ -0,0 +1,47 @@
+package com.baeldung.algorithms.multiswarm;
+
+/**
+ * Constants used by the Multi-swarm optimization algorithms.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class Constants {
+
+	/**
+	 * The inertia factor encourages a particle to continue moving in its
+	 * current direction.
+	 */
+	public static final double INERTIA_FACTOR = 0.729;
+
+	/**
+	 * The cognitive weight encourages a particle to move toward its historical
+	 * best-known position.
+	 */
+	public static final double COGNITIVE_WEIGHT = 1.49445;
+
+	/**
+	 * The social weight encourages a particle to move toward the best-known
+	 * position found by any of the particle’s swarm-mates.
+	 */
+	public static final double SOCIAL_WEIGHT = 1.49445;
+
+	/**
+	 * The global weight encourages a particle to move toward the best-known
+	 * position found by any particle in any swarm.
+	 */
+	public static final double GLOBAL_WEIGHT = 0.3645;
+
+	/**
+	 * Upper bound for the random generation. We use it to reduce the
+	 * computation time since we can rawly estimate it.
+	 */
+	public static final int PARTICLE_UPPER_BOUND = 10000000;
+
+	/**
+	 * Private constructor for utility class.
+	 */
+	private Constants() {
+	}
+
+}
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/FitnessFunction.java b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/FitnessFunction.java
new file mode 100644
index 0000000000..2d86ec8d94
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/FitnessFunction.java
@@ -0,0 +1,21 @@
+package com.baeldung.algorithms.multiswarm;
+
+/**
+ * Interface for a fitness function, used to decouple the main algorithm logic
+ * from the specific problem solution.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public interface FitnessFunction {
+
+	/**
+	 * Returns the fitness of a particle given its position.
+	 * 
+	 * @param particlePosition
+	 *            the position of the particle
+	 * @return the fitness of the particle
+	 */
+	public double getFitness(long[] particlePosition);
+
+}
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Multiswarm.java b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Multiswarm.java
new file mode 100644
index 0000000000..ef60726278
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Multiswarm.java
@@ -0,0 +1,227 @@
+package com.baeldung.algorithms.multiswarm;
+
+import java.util.Arrays;
+import java.util.Random;
+
+/**
+ * Represents a collection of {@link Swarm}.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class Multiswarm {
+
+	/**
+	 * The swarms managed by this multiswarm.
+	 */
+	private Swarm[] swarms;
+
+	/**
+	 * The best position found within all the {@link #swarms}.
+	 */
+	private long[] bestPosition;
+
+	/**
+	 * The best fitness score found within all the {@link #swarms}.
+	 */
+	private double bestFitness = Double.NEGATIVE_INFINITY;
+
+	/**
+	 * A random generator.
+	 */
+	private Random random = new Random();
+
+	/**
+	 * The fitness function used to determine how good is a particle.
+	 */
+	private FitnessFunction fitnessFunction;
+
+	/**
+	 * Instantiates a new Multiswarm.
+	 * 
+	 * @param numSwarms
+	 *            the number of {@link #swarms}
+	 * @param particlesPerSwarm
+	 *            the number of particle for each {@link #swarms}
+	 * @param fitnessFunction
+	 *            the {@link #fitnessFunction}
+	 */
+	public Multiswarm(int numSwarms, int particlesPerSwarm, FitnessFunction fitnessFunction) {
+		this.fitnessFunction = fitnessFunction;
+		this.swarms = new Swarm[numSwarms];
+		for (int i = 0; i < numSwarms; i++) {
+			swarms[i] = new Swarm(particlesPerSwarm);
+		}
+	}
+
+	/**
+	 * Main loop of the algorithm. Iterates all particles of all
+	 * {@link #swarms}. For each particle, computes the new fitness and checks
+	 * if a new best position has been found among itself, the swarm and all the
+	 * swarms and finally updates the particle position and speed.
+	 */
+	public void mainLoop() {
+		for (Swarm swarm : swarms) {
+			for (Particle particle : swarm.getParticles()) {
+
+				long[] particleOldPosition = particle.getPosition().clone();
+
+				// Calculate the particle fitness.
+				particle.setFitness(fitnessFunction.getFitness(particleOldPosition));
+
+				// Check if a new best position has been found for the particle
+				// itself, within the swarm and the multiswarm.
+				if (particle.getFitness() > particle.getBestFitness()) {
+					particle.setBestFitness(particle.getFitness());
+					particle.setBestPosition(particleOldPosition);
+
+					if (particle.getFitness() > swarm.getBestFitness()) {
+						swarm.setBestFitness(particle.getFitness());
+						swarm.setBestPosition(particleOldPosition);
+
+						if (swarm.getBestFitness() > bestFitness) {
+							bestFitness = swarm.getBestFitness();
+							bestPosition = swarm.getBestPosition().clone();
+						}
+
+					}
+				}
+
+				// Updates the particle position by adding the speed to the
+				// actual position.
+				long[] position = particle.getPosition();
+				long[] speed = particle.getSpeed();
+
+				position[0] += speed[0];
+				position[1] += speed[1];
+
+				// Updates the particle speed.
+				speed[0] = getNewParticleSpeedForIndex(particle, swarm, 0);
+				speed[1] = getNewParticleSpeedForIndex(particle, swarm, 1);
+			}
+		}
+	}
+
+	/**
+	 * Computes a new speed for a given particle of a given swarm on a given
+	 * axis. The new speed is computed using the formula:
+	 * 
+	 * <pre>
+	 * ({@link Constants#INERTIA_FACTOR} * {@link Particle#getSpeed()}) + 
+	 * (({@link Constants#COGNITIVE_WEIGHT} * random(0,1)) * ({@link Particle#getBestPosition()} - {@link Particle#getPosition()})) +
+	 * (({@link Constants#SOCIAL_WEIGHT} * random(0,1)) * ({@link Swarm#getBestPosition()} - {@link Particle#getPosition()})) + 
+	 * (({@link Constants#GLOBAL_WEIGHT} * random(0,1)) * ({@link #bestPosition} - {@link Particle#getPosition()}))
+	 * </pre>
+	 *
+	 * @param particle
+	 *            the particle whose new speed needs to be computed
+	 * @param swarm
+	 *            the swarm which contains the particle
+	 * @param index
+	 *            the index of the particle axis whose speeds needs to be
+	 *            computed
+	 * @return the new speed of the particle passed on the given axis
+	 */
+	private int getNewParticleSpeedForIndex(Particle particle, Swarm swarm, int index) {
+		return (int) ((Constants.INERTIA_FACTOR * particle.getSpeed()[index])
+				+ (randomizePercentage(Constants.COGNITIVE_WEIGHT)
+						* (particle.getBestPosition()[index] - particle.getPosition()[index]))
+				+ (randomizePercentage(Constants.SOCIAL_WEIGHT)
+						* (swarm.getBestPosition()[index] - particle.getPosition()[index]))
+				+ (randomizePercentage(Constants.GLOBAL_WEIGHT)
+						* (bestPosition[index] - particle.getPosition()[index])));
+	}
+
+	/**
+	 * Returns a random number between 0 and the value passed as argument.
+	 *
+	 * @param value
+	 *            the value to randomize
+	 * @return a random value between 0 and the one passed as argument
+	 */
+	private double randomizePercentage(double value) {
+		return random.nextDouble() * value;
+	}
+
+	/**
+	 * Gets the {@link #bestPosition}.
+	 *
+	 * @return the {@link #bestPosition}
+	 */
+	public long[] getBestPosition() {
+		return bestPosition;
+	}
+
+	/**
+	 * Gets the {@link #bestFitness}.
+	 *
+	 * @return the {@link #bestFitness}
+	 */
+	public double getBestFitness() {
+		return bestFitness;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#hashCode()
+	 */
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		long temp;
+		temp = Double.doubleToLongBits(bestFitness);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result + Arrays.hashCode(bestPosition);
+		result = prime * result + ((fitnessFunction == null) ? 0 : fitnessFunction.hashCode());
+		result = prime * result + ((random == null) ? 0 : random.hashCode());
+		result = prime * result + Arrays.hashCode(swarms);
+		return result;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#equals(java.lang.Object)
+	 */
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		Multiswarm other = (Multiswarm) obj;
+		if (Double.doubleToLongBits(bestFitness) != Double.doubleToLongBits(other.bestFitness))
+			return false;
+		if (!Arrays.equals(bestPosition, other.bestPosition))
+			return false;
+		if (fitnessFunction == null) {
+			if (other.fitnessFunction != null)
+				return false;
+		} else if (!fitnessFunction.equals(other.fitnessFunction))
+			return false;
+		if (random == null) {
+			if (other.random != null)
+				return false;
+		} else if (!random.equals(other.random))
+			return false;
+		if (!Arrays.equals(swarms, other.swarms))
+			return false;
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#toString()
+	 */
+	@Override
+	public String toString() {
+		return "Multiswarm [swarms=" + Arrays.toString(swarms) + ", bestPosition=" + Arrays.toString(bestPosition)
+				+ ", bestFitness=" + bestFitness + ", random=" + random + ", fitnessFunction=" + fitnessFunction + "]";
+	}
+
+}
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Particle.java b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Particle.java
new file mode 100644
index 0000000000..5930a94267
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Particle.java
@@ -0,0 +1,204 @@
+package com.baeldung.algorithms.multiswarm;
+
+import java.util.Arrays;
+
+/**
+ * Represents a particle, the basic component of a {@link Swarm}.
+ * 
+ * @author Donato Rimenti
+ * 
+ */
+public class Particle {
+
+	/**
+	 * The current position of this particle.
+	 */
+	private long[] position;
+
+	/**
+	 * The speed of this particle.
+	 */
+	private long[] speed;
+
+	/**
+	 * The fitness of this particle for the current position.
+	 */
+	private double fitness;
+
+	/**
+	 * The best position found by this particle.
+	 */
+	private long[] bestPosition;
+
+	/**
+	 * The best fitness found by this particle.
+	 */
+	private double bestFitness = Double.NEGATIVE_INFINITY;
+
+	/**
+	 * Instantiates a new Particle.
+	 *
+	 * @param initialPosition
+	 *            the initial {@link #position}
+	 * @param initialSpeed
+	 *            the initial {@link #speed}
+	 */
+	public Particle(long[] initialPosition, long[] initialSpeed) {
+		this.position = initialPosition;
+		this.speed = initialSpeed;
+	}
+
+	/**
+	 * Gets the {@link #position}.
+	 *
+	 * @return the {@link #position}
+	 */
+	public long[] getPosition() {
+		return position;
+	}
+
+	/**
+	 * Gets the {@link #speed}.
+	 *
+	 * @return the {@link #speed}
+	 */
+	public long[] getSpeed() {
+		return speed;
+	}
+
+	/**
+	 * Gets the {@link #fitness}.
+	 *
+	 * @return the {@link #fitness}
+	 */
+	public double getFitness() {
+		return fitness;
+	}
+
+	/**
+	 * Gets the {@link #bestPosition}.
+	 *
+	 * @return the {@link #bestPosition}
+	 */
+	public long[] getBestPosition() {
+		return bestPosition;
+	}
+
+	/**
+	 * Gets the {@link #bestFitness}.
+	 *
+	 * @return the {@link #bestFitness}
+	 */
+	public double getBestFitness() {
+		return bestFitness;
+	}
+
+	/**
+	 * Sets the {@link #position}.
+	 *
+	 * @param position
+	 *            the new {@link #position}
+	 */
+	public void setPosition(long[] position) {
+		this.position = position;
+	}
+
+	/**
+	 * Sets the {@link #speed}.
+	 *
+	 * @param speed
+	 *            the new {@link #speed}
+	 */
+	public void setSpeed(long[] speed) {
+		this.speed = speed;
+	}
+
+	/**
+	 * Sets the {@link #fitness}.
+	 *
+	 * @param fitness
+	 *            the new {@link #fitness}
+	 */
+	public void setFitness(double fitness) {
+		this.fitness = fitness;
+	}
+
+	/**
+	 * Sets the {@link #bestPosition}.
+	 *
+	 * @param bestPosition
+	 *            the new {@link #bestPosition}
+	 */
+	public void setBestPosition(long[] bestPosition) {
+		this.bestPosition = bestPosition;
+	}
+
+	/**
+	 * Sets the {@link #bestFitness}.
+	 *
+	 * @param bestFitness
+	 *            the new {@link #bestFitness}
+	 */
+	public void setBestFitness(double bestFitness) {
+		this.bestFitness = bestFitness;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#hashCode()
+	 */
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		long temp;
+		temp = Double.doubleToLongBits(bestFitness);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result + Arrays.hashCode(bestPosition);
+		temp = Double.doubleToLongBits(fitness);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result + Arrays.hashCode(position);
+		result = prime * result + Arrays.hashCode(speed);
+		return result;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#equals(java.lang.Object)
+	 */
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		Particle other = (Particle) obj;
+		if (Double.doubleToLongBits(bestFitness) != Double.doubleToLongBits(other.bestFitness))
+			return false;
+		if (!Arrays.equals(bestPosition, other.bestPosition))
+			return false;
+		if (Double.doubleToLongBits(fitness) != Double.doubleToLongBits(other.fitness))
+			return false;
+		if (!Arrays.equals(position, other.position))
+			return false;
+		if (!Arrays.equals(speed, other.speed))
+			return false;
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#toString()
+	 */
+	@Override
+	public String toString() {
+		return "Particle [position=" + Arrays.toString(position) + ", speed=" + Arrays.toString(speed) + ", fitness="
+				+ fitness + ", bestPosition=" + Arrays.toString(bestPosition) + ", bestFitness=" + bestFitness + "]";
+	}
+
+}
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Swarm.java b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Swarm.java
new file mode 100644
index 0000000000..e6d37bb7e6
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/multiswarm/Swarm.java
@@ -0,0 +1,155 @@
+package com.baeldung.algorithms.multiswarm;
+
+import java.util.Arrays;
+import java.util.Random;
+
+/**
+ * Represents a collection of {@link Particle}.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class Swarm {
+
+	/**
+	 * The particles of this swarm.
+	 */
+	private Particle[] particles;
+
+	/**
+	 * The best position found within the particles of this swarm.
+	 */
+	private long[] bestPosition;
+
+	/**
+	 * The best fitness score found within the particles of this swarm.
+	 */
+	private double bestFitness = Double.NEGATIVE_INFINITY;
+
+	/**
+	 * A random generator.
+	 */
+	private Random random = new Random();
+
+	/**
+	 * Instantiates a new Swarm.
+	 *
+	 * @param numParticles
+	 *            the number of particles of the swarm
+	 */
+	public Swarm(int numParticles) {
+		particles = new Particle[numParticles];
+		for (int i = 0; i < numParticles; i++) {
+			long[] initialParticlePosition = { random.nextInt(Constants.PARTICLE_UPPER_BOUND),
+					random.nextInt(Constants.PARTICLE_UPPER_BOUND) };
+			long[] initialParticleSpeed = { random.nextInt(Constants.PARTICLE_UPPER_BOUND),
+					random.nextInt(Constants.PARTICLE_UPPER_BOUND) };
+			particles[i] = new Particle(initialParticlePosition, initialParticleSpeed);
+		}
+	}
+
+	/**
+	 * Gets the {@link #particles}.
+	 *
+	 * @return the {@link #particles}
+	 */
+	public Particle[] getParticles() {
+		return particles;
+	}
+
+	/**
+	 * Gets the {@link #bestPosition}.
+	 *
+	 * @return the {@link #bestPosition}
+	 */
+	public long[] getBestPosition() {
+		return bestPosition;
+	}
+
+	/**
+	 * Gets the {@link #bestFitness}.
+	 *
+	 * @return the {@link #bestFitness}
+	 */
+	public double getBestFitness() {
+		return bestFitness;
+	}
+
+	/**
+	 * Sets the {@link #bestPosition}.
+	 *
+	 * @param bestPosition
+	 *            the new {@link #bestPosition}
+	 */
+	public void setBestPosition(long[] bestPosition) {
+		this.bestPosition = bestPosition;
+	}
+
+	/**
+	 * Sets the {@link #bestFitness}.
+	 *
+	 * @param bestFitness
+	 *            the new {@link #bestFitness}
+	 */
+	public void setBestFitness(double bestFitness) {
+		this.bestFitness = bestFitness;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#hashCode()
+	 */
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		long temp;
+		temp = Double.doubleToLongBits(bestFitness);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result + Arrays.hashCode(bestPosition);
+		result = prime * result + Arrays.hashCode(particles);
+		result = prime * result + ((random == null) ? 0 : random.hashCode());
+		return result;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#equals(java.lang.Object)
+	 */
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		Swarm other = (Swarm) obj;
+		if (Double.doubleToLongBits(bestFitness) != Double.doubleToLongBits(other.bestFitness))
+			return false;
+		if (!Arrays.equals(bestPosition, other.bestPosition))
+			return false;
+		if (!Arrays.equals(particles, other.particles))
+			return false;
+		if (random == null) {
+			if (other.random != null)
+				return false;
+		} else if (!random.equals(other.random))
+			return false;
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see java.lang.Object#toString()
+	 */
+	@Override
+	public String toString() {
+		return "Swarm [particles=" + Arrays.toString(particles) + ", bestPosition=" + Arrays.toString(bestPosition)
+				+ ", bestFitness=" + bestFitness + ", random=" + random + "]";
+	}
+
+}
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/BacktrackingAlgorithm.java b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/BacktrackingAlgorithm.java
index ff426cbe68..4b37558aab 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/BacktrackingAlgorithm.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/BacktrackingAlgorithm.java
@@ -40,15 +40,15 @@ public class BacktrackingAlgorithm {
     }
 
     private boolean solve(int[][] board) {
-        for (int r = BOARD_START_INDEX; r < BOARD_SIZE; r++) {
-            for (int c = BOARD_START_INDEX; c < BOARD_SIZE; c++) {
-                if (board[r][c] == NO_VALUE) {
+        for (int row = BOARD_START_INDEX; row < BOARD_SIZE; row++) {
+            for (int column = BOARD_START_INDEX; column < BOARD_SIZE; column++) {
+                if (board[row][column] == NO_VALUE) {
                     for (int k = MIN_VALUE; k <= MAX_VALUE; k++) {
-                        board[r][c] = k;
-                        if (isValid(board, r, c) && solve(board)) {
+                        board[row][column] = k;
+                        if (isValid(board, row, column) && solve(board)) {
                             return true;
                         }
-                        board[r][c] = NO_VALUE;
+                        board[row][column] = NO_VALUE;
                     }
                     return false;
                 }
@@ -57,44 +57,44 @@ public class BacktrackingAlgorithm {
         return true;
     }
 
-    private boolean isValid(int[][] board, int r, int c) {
-        return rowConstraint(board, r) &&
-          columnConstraint(board, c) &&
-          subsectionConstraint(board, r, c);
+    private boolean isValid(int[][] board, int row, int column) {
+        return rowConstraint(board, row) &&
+          columnConstraint(board, column) &&
+          subsectionConstraint(board, row, column);
     }
 
-    private boolean subsectionConstraint(int[][] board, int r, int c) {
+    private boolean subsectionConstraint(int[][] board, int row, int column) {
         boolean[] constraint = new boolean[BOARD_SIZE];
-        int subsectionRowStart = (r / SUBSECTION_SIZE) * SUBSECTION_SIZE;
+        int subsectionRowStart = (row / SUBSECTION_SIZE) * SUBSECTION_SIZE;
         int subsectionRowEnd = subsectionRowStart + SUBSECTION_SIZE;
 
-        int subsectionColumnStart = (c / SUBSECTION_SIZE) * SUBSECTION_SIZE;
+        int subsectionColumnStart = (column / SUBSECTION_SIZE) * SUBSECTION_SIZE;
         int subsectionColumnEnd = subsectionColumnStart + SUBSECTION_SIZE;
 
-        for (int i = subsectionRowStart; i < subsectionRowEnd; i++) {
-            for (int j = subsectionColumnStart; j < subsectionColumnEnd; j++) {
-                if (!checkConstraint(board, i, constraint, j)) return false;
+        for (int r = subsectionRowStart; r < subsectionRowEnd; r++) {
+            for (int c = subsectionColumnStart; c < subsectionColumnEnd; c++) {
+                if (!checkConstraint(board, r, constraint, c)) return false;
             }
         }
         return true;
     }
 
-    private boolean columnConstraint(int[][] board, int c) {
+    private boolean columnConstraint(int[][] board, int column) {
         boolean[] constraint = new boolean[BOARD_SIZE];
         return IntStream.range(BOARD_START_INDEX, BOARD_SIZE)
-          .allMatch(i -> checkConstraint(board, i, constraint, c));
+          .allMatch(row -> checkConstraint(board, row, constraint, column));
     }
 
-    private boolean rowConstraint(int[][] board, int r) {
+    private boolean rowConstraint(int[][] board, int row) {
         boolean[] constraint = new boolean[BOARD_SIZE];
         return IntStream.range(BOARD_START_INDEX, BOARD_SIZE)
-          .allMatch(i -> checkConstraint(board, r, constraint, i));
+          .allMatch(column -> checkConstraint(board, row, constraint, column));
     }
 
-    private boolean checkConstraint(int[][] board, int r, boolean[] constraint, int c) {
-        if (board[r][c] != NO_VALUE) {
-            if (!constraint[board[r][c] - 1]) {
-                constraint[board[r][c] - 1] = true;
+    private boolean checkConstraint(int[][] board, int row, boolean[] constraint, int column) {
+        if (board[row][column] != NO_VALUE) {
+            if (!constraint[board[row][column] - 1]) {
+                constraint[board[row][column] - 1] = true;
             } else {
                 return false;
             }
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingLinksAlgorithm.java b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingLinksAlgorithm.java
index 76b686afa6..df02ff3d11 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingLinksAlgorithm.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingLinksAlgorithm.java
@@ -34,8 +34,8 @@ public class DancingLinksAlgorithm {
         dlx.runSolver();
     }
 
-    private int getIndex(int row, int col, int num) {
-        return (row - 1) * BOARD_SIZE * BOARD_SIZE + (col - 1) * BOARD_SIZE + (num - 1);
+    private int getIndex(int row, int column, int num) {
+        return (row - 1) * BOARD_SIZE * BOARD_SIZE + (column - 1) * BOARD_SIZE + (num - 1);
     }
 
     private boolean[][] createExactCoverBoard() {
@@ -51,12 +51,12 @@ public class DancingLinksAlgorithm {
     }
 
     private int checkSubsectionConstraint(boolean[][] coverBoard, int hBase) {
-        for (int br = COVER_START_INDEX; br <= BOARD_SIZE; br += SUBSECTION_SIZE) {
-            for (int bc = COVER_START_INDEX; bc <= BOARD_SIZE; bc += SUBSECTION_SIZE) {
+        for (int row = COVER_START_INDEX; row <= BOARD_SIZE; row += SUBSECTION_SIZE) {
+            for (int column = COVER_START_INDEX; column <= BOARD_SIZE; column += SUBSECTION_SIZE) {
                 for (int n = COVER_START_INDEX; n <= BOARD_SIZE; n++, hBase++) {
-                    for (int rDelta = 0; rDelta < SUBSECTION_SIZE; rDelta++) {
-                        for (int cDelta = 0; cDelta < SUBSECTION_SIZE; cDelta++) {
-                            int index = getIndex(br + rDelta, bc + cDelta, n);
+                    for (int rowDelta = 0; rowDelta < SUBSECTION_SIZE; rowDelta++) {
+                        for (int columnDelta = 0; columnDelta < SUBSECTION_SIZE; columnDelta++) {
+                            int index = getIndex(row + rowDelta, column + columnDelta, n);
                             coverBoard[index][hBase] = true;
                         }
                     }
@@ -67,10 +67,10 @@ public class DancingLinksAlgorithm {
     }
 
     private int checkColumnConstraint(boolean[][] coverBoard, int hBase) {
-        for (int c = COVER_START_INDEX; c <= BOARD_SIZE; c++) {
+        for (int column = COVER_START_INDEX; column <= BOARD_SIZE; column++) {
             for (int n = COVER_START_INDEX; n <= BOARD_SIZE; n++, hBase++) {
-                for (int r1 = COVER_START_INDEX; r1 <= BOARD_SIZE; r1++) {
-                    int index = getIndex(r1, c, n);
+                for (int row = COVER_START_INDEX; row <= BOARD_SIZE; row++) {
+                    int index = getIndex(row, column, n);
                     coverBoard[index][hBase] = true;
                 }
             }
@@ -79,10 +79,10 @@ public class DancingLinksAlgorithm {
     }
 
     private int checkRowConstraint(boolean[][] coverBoard, int hBase) {
-        for (int r = COVER_START_INDEX; r <= BOARD_SIZE; r++) {
+        for (int row = COVER_START_INDEX; row <= BOARD_SIZE; row++) {
             for (int n = COVER_START_INDEX; n <= BOARD_SIZE; n++, hBase++) {
-                for (int c1 = COVER_START_INDEX; c1 <= BOARD_SIZE; c1++) {
-                    int index = getIndex(r, c1, n);
+                for (int column = COVER_START_INDEX; column <= BOARD_SIZE; column++) {
+                    int index = getIndex(row, column, n);
                     coverBoard[index][hBase] = true;
                 }
             }
@@ -91,10 +91,10 @@ public class DancingLinksAlgorithm {
     }
 
     private int checkCellConstraint(boolean[][] coverBoard, int hBase) {
-        for (int r = COVER_START_INDEX; r <= BOARD_SIZE; r++) {
-            for (int c = COVER_START_INDEX; c <= BOARD_SIZE; c++, hBase++) {
+        for (int row = COVER_START_INDEX; row <= BOARD_SIZE; row++) {
+            for (int column = COVER_START_INDEX; column <= BOARD_SIZE; column++, hBase++) {
                 for (int n = COVER_START_INDEX; n <= BOARD_SIZE; n++) {
-                    int index = getIndex(r, c, n);
+                    int index = getIndex(row, column, n);
                     coverBoard[index][hBase] = true;
                 }
             }
@@ -104,13 +104,13 @@ public class DancingLinksAlgorithm {
 
     private boolean[][] initializeExactCoverBoard(int[][] board) {
         boolean[][] coverBoard = createExactCoverBoard();
-        for (int i = COVER_START_INDEX; i <= BOARD_SIZE; i++) {
-            for (int j = COVER_START_INDEX; j <= BOARD_SIZE; j++) {
-                int n = board[i - 1][j - 1];
+        for (int row = COVER_START_INDEX; row <= BOARD_SIZE; row++) {
+            for (int column = COVER_START_INDEX; column <= BOARD_SIZE; column++) {
+                int n = board[row - 1][column - 1];
                 if (n != NO_VALUE) {
                     for (int num = MIN_VALUE; num <= MAX_VALUE; num++) {
                         if (num != n) {
-                            Arrays.fill(coverBoard[getIndex(i, j, num)], false);
+                            Arrays.fill(coverBoard[getIndex(row, column, num)], false);
                         }
                     }
                 }
diff --git a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingNode.java b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingNode.java
index b494eba9ef..2422ff0dff 100644
--- a/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingNode.java
+++ b/algorithms/src/main/java/com/baeldung/algorithms/sudoku/DancingNode.java
@@ -4,21 +4,21 @@ class DancingNode {
     DancingNode L, R, U, D;
     ColumnNode C;
 
-    DancingNode hookDown(DancingNode n1) {
-        assert (this.C == n1.C);
-        n1.D = this.D;
-        n1.D.U = n1;
-        n1.U = this;
-        this.D = n1;
-        return n1;
+    DancingNode hookDown(DancingNode node) {
+        assert (this.C == node.C);
+        node.D = this.D;
+        node.D.U = node;
+        node.U = this;
+        this.D = node;
+        return node;
     }
 
-    DancingNode hookRight(DancingNode n1) {
-        n1.R = this.R;
-        n1.R.L = n1;
-        n1.L = this;
-        this.R = n1;
-        return n1;
+    DancingNode hookRight(DancingNode node) {
+        node.R = this.R;
+        node.R.L = node;
+        node.L = this;
+        this.R = node;
+        return node;
     }
 
     void unlinkLR() {
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/LolFitnessFunction.java b/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/LolFitnessFunction.java
new file mode 100644
index 0000000000..726d4c135d
--- /dev/null
+++ b/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/LolFitnessFunction.java
@@ -0,0 +1,52 @@
+package com.baeldung.algorithms.multiswarm;
+
+/**
+ * Specific fitness function implementation to solve the League of Legends
+ * problem. This is the problem statement: <br>
+ * <br>
+ * In League of Legends, a player's Effective Health when defending against
+ * physical damage is given by E=H(100+A)/100, where H is health and A is armor.
+ * Health costs 2.5 gold per unit, and Armor costs 18 gold per unit. You have
+ * 3600 gold, and you need to optimize the effectiveness E of your health and
+ * armor to survive as long as possible against the enemy team's attacks. How
+ * much of each should you buy? <br>
+ * <br>
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class LolFitnessFunction implements FitnessFunction {
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see
+	 * com.baeldung.algorithms.multiswarm.FitnessFunction#getFitness(long[])
+	 */
+	@Override
+	public double getFitness(long[] particlePosition) {
+
+		long health = particlePosition[0];
+		long armor = particlePosition[1];
+
+		// No negatives values accepted.
+		if (health < 0 && armor < 0) {
+			return -(health * armor);
+		} else if (health < 0) {
+			return health;
+		} else if (armor < 0) {
+			return armor;
+		}
+
+		// Checks if the solution is actually feasible provided our gold.
+		double cost = (health * 2.5) + (armor * 18);
+		if (cost > 3600) {
+			return 3600 - cost;
+		} else {
+			// Check how good is the solution.
+			long fitness = (health * (100 + armor)) / 100;
+			return fitness;
+		}
+	}
+
+}
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/MultiswarmUnitTest.java b/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/MultiswarmUnitTest.java
new file mode 100644
index 0000000000..3455cd3932
--- /dev/null
+++ b/algorithms/src/test/java/com/baeldung/algorithms/multiswarm/MultiswarmUnitTest.java
@@ -0,0 +1,54 @@
+package com.baeldung.algorithms.multiswarm;
+
+import org.junit.Assert;
+import org.junit.Rule;
+import org.junit.Test;
+
+import com.baeldung.algorithms.support.MayFailRule;
+
+/**
+ * Test for {@link Multiswarm}.
+ * 
+ * @author Donato Rimenti
+ * 
+ */
+public class MultiswarmUnitTest {
+
+	/**
+	 * Rule for handling expected failures. We use this since this test may
+	 * actually fail due to bad luck in the random generation.
+	 */
+	@Rule
+	public MayFailRule mayFailRule = new MayFailRule();
+
+	/**
+	 * Tests the multiswarm algorithm with a generic problem. The problem is the
+	 * following: <br>
+	 * <br>
+	 * In League of Legends, a player's Effective Health when defending against
+	 * physical damage is given by E=H(100+A)/100, where H is health and A is
+	 * armor. Health costs 2.5 gold per unit, and Armor costs 18 gold per unit.
+	 * You have 3600 gold, and you need to optimize the effectiveness E of your
+	 * health and armor to survive as long as possible against the enemy team's
+	 * attacks. How much of each should you buy? <br>
+	 * <br>
+	 * The solution is H = 1080, A = 50 for a total fitness of 1620. Tested with
+	 * 50 swarms each with 1000 particles.
+	 */
+	@Test
+	public void givenMultiswarm_whenThousandIteration_thenSolutionFound() {
+		Multiswarm multiswarm = new Multiswarm(50, 1000, new LolFitnessFunction());
+
+		// Iterates 1000 times through the main loop and prints the result.
+		for (int i = 0; i < 1000; i++) {
+			multiswarm.mainLoop();
+		}
+
+		System.out.println("Best fitness found: " + multiswarm.getBestFitness() + "[" + multiswarm.getBestPosition()[0]
+				+ "," + multiswarm.getBestPosition()[1] + "]");
+		Assert.assertEquals(1080, multiswarm.getBestPosition()[0]);
+		Assert.assertEquals(50, multiswarm.getBestPosition()[1]);
+		Assert.assertEquals(1620, (int) multiswarm.getBestFitness());
+	}
+
+}
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/support/MayFailRule.java b/algorithms/src/test/java/com/baeldung/algorithms/support/MayFailRule.java
new file mode 100644
index 0000000000..91df78ce4a
--- /dev/null
+++ b/algorithms/src/test/java/com/baeldung/algorithms/support/MayFailRule.java
@@ -0,0 +1,38 @@
+package com.baeldung.algorithms.support;
+
+import org.junit.Rule;
+import org.junit.rules.TestRule;
+import org.junit.runner.Description;
+import org.junit.runners.model.Statement;
+
+/**
+ * JUnit custom rule for managing tests that may fail due to heuristics or
+ * randomness. In order to use this, just instantiate this object as a public
+ * field inside the test class and annotate it with {@link Rule}.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class MayFailRule implements TestRule {
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.junit.rules.TestRule#apply(org.junit.runners.model.Statement,
+	 * org.junit.runner.Description)
+	 */
+	@Override
+	public Statement apply(Statement base, Description description) {
+		return new Statement() {
+			@Override
+			public void evaluate() throws Throwable {
+				try {
+					base.evaluate();
+				} catch (Throwable e) {
+					// Ignore the exception since we expect this.
+				}
+			}
+		};
+	}
+
+}
diff --git a/apache-zookeeper/pom.xml b/apache-zookeeper/pom.xml
new file mode 100644
index 0000000000..6d49d74ade
--- /dev/null
+++ b/apache-zookeeper/pom.xml
@@ -0,0 +1,30 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.baeldung</groupId>
+	<artifactId>apache-zookeeper</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<packaging>jar</packaging>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.apache.zookeeper</groupId>
+			<artifactId>zookeeper</artifactId>
+			<version>3.3.2</version>
+			<exclusions>
+				<exclusion>
+					<groupId>com.sun.jmx</groupId>
+					<artifactId>jmxri</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>com.sun.jdmk</groupId>
+					<artifactId>jmxtools</artifactId>
+				</exclusion>
+				<exclusion>
+					<groupId>javax.jms</groupId>
+					<artifactId>jms</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+	</dependencies>
+</project>
diff --git a/apache-zookeeper/src/main/java/com/baeldung/zookeeper/connection/ZKConnection.java b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/connection/ZKConnection.java
new file mode 100644
index 0000000000..0678250d57
--- /dev/null
+++ b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/connection/ZKConnection.java
@@ -0,0 +1,33 @@
+package com.baeldung.zookeeper.connection;
+
+import java.io.IOException;
+import java.util.concurrent.CountDownLatch;
+
+import org.apache.zookeeper.WatchedEvent;
+import org.apache.zookeeper.Watcher;
+import org.apache.zookeeper.Watcher.Event.KeeperState;
+import org.apache.zookeeper.ZooKeeper;
+
+public class ZKConnection {
+    private ZooKeeper zoo;
+    final CountDownLatch connectionLatch = new CountDownLatch(1);
+
+    public ZKConnection() {
+    }
+
+    public ZooKeeper connect(String host) throws IOException, InterruptedException {
+        zoo = new ZooKeeper(host, 2000, new Watcher() {
+            public void process(WatchedEvent we) {
+                if (we.getState() == KeeperState.SyncConnected) {
+                    connectionLatch.countDown();
+                }
+            }
+        });
+        connectionLatch.await();
+        return zoo;
+    }
+
+    public void close() throws InterruptedException {
+        zoo.close();
+    }
+}
diff --git a/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManager.java b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManager.java
new file mode 100644
index 0000000000..0c0ad52123
--- /dev/null
+++ b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManager.java
@@ -0,0 +1,35 @@
+package com.baeldung.zookeeper.manager;
+
+import org.apache.zookeeper.KeeperException;
+
+public interface ZKManager {
+    /**
+     * Create a Znode and save some data
+     * 
+     * @param path
+     * @param data
+     * @throws KeeperException
+     * @throws InterruptedException
+     */
+    public void create(String path, byte[] data) throws KeeperException, InterruptedException;
+
+    /**
+     * Get ZNode Data
+     * 
+     * @param path
+     * @param boolean watchFlag
+     * @throws KeeperException
+     * @throws InterruptedException
+     */
+    public Object getZNodeData(String path, boolean watchFlag);
+
+    /**
+     * Update the ZNode Data
+     * 
+     * @param path
+     * @param data
+     * @throws KeeperException
+     * @throws InterruptedException
+     */
+    public void update(String path, byte[] data) throws KeeperException, InterruptedException, KeeperException;
+}
diff --git a/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManagerImpl.java b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManagerImpl.java
new file mode 100644
index 0000000000..adf76bc0f2
--- /dev/null
+++ b/apache-zookeeper/src/main/java/com/baeldung/zookeeper/manager/ZKManagerImpl.java
@@ -0,0 +1,58 @@
+package com.baeldung.zookeeper.manager;
+
+import org.apache.zookeeper.CreateMode;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.ZooDefs;
+import org.apache.zookeeper.ZooKeeper;
+
+import com.baeldung.zookeeper.connection.ZKConnection;
+
+public class ZKManagerImpl implements ZKManager {
+    private static ZooKeeper zkeeper;
+    private static ZKConnection zkConnection;
+
+    public ZKManagerImpl() {
+        initialize();
+    }
+
+    /** * Initialize connection */
+    private void initialize() {
+        try {
+            zkConnection = new ZKConnection();
+            zkeeper = zkConnection.connect("localhost");
+        } catch (Exception e) {
+            System.out.println(e.getMessage());
+        }
+    }
+
+    public void closeConnection() {
+        try {
+            zkConnection.close();
+        } catch (InterruptedException e) {
+            System.out.println(e.getMessage());
+        }
+    }
+
+    public void create(String path, byte[] data) throws KeeperException, InterruptedException {
+        zkeeper.create(path, data, ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
+    }
+
+    public Object getZNodeData(String path, boolean watchFlag) {
+        try {
+            byte[] b = null;
+            b = zkeeper.getData(path, null, null);
+            String data = new String(b, "UTF-8");
+            System.out.println(data);
+            return data;
+        } catch (Exception e) {
+            System.out.println(e.getMessage());
+        }
+        return null;
+    }
+
+    public void update(String path, byte[] data) throws KeeperException, InterruptedException {
+        int version = zkeeper.exists(path, true)
+            .getVersion();
+        zkeeper.setData(path, data, version);
+    }
+}
diff --git a/checker-plugin/pom.xml b/checker-plugin/pom.xml
new file mode 100644
index 0000000000..bc7a669d4f
--- /dev/null
+++ b/checker-plugin/pom.xml
@@ -0,0 +1,114 @@
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung</groupId>
+    <artifactId>checker-plugin</artifactId>
+    <packaging>jar</packaging>
+    <version>1.0-SNAPSHOT</version>
+    <name>checker-plugin</name>
+    <url>http://maven.apache.org</url>
+
+    <!-- https://checkerframework.org/manual/#maven -->
+
+    <properties>
+        <!-- These properties will be set by the Maven Dependency plugin -->
+        <annotatedJdk>${org.checkerframework:jdk8:jar}</annotatedJdk>
+        <!-- Uncomment to use the Type Annotations compiler. -->
+        <!--
+        <typeAnnotationsJavac>${org.checkerframework:compiler:jar}</typeAnnotationsJavac>
+        -->
+    </properties>
+
+    <dependencies>
+
+
+        <!-- Annotations from the Checker Framework: nullness, interning, locking, ... -->
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>checker-qual</artifactId>
+            <version>2.3.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>checker</artifactId>
+            <version>2.3.1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>jdk8</artifactId>
+            <version>2.3.1</version>
+        </dependency>
+        <!-- The Type Annotations compiler. Uncomment if using annotations in comments. -->
+        <dependency>
+            <groupId>org.checkerframework</groupId>
+            <artifactId>compiler</artifactId>
+            <version>2.3.1</version>
+        </dependency>
+
+    </dependencies>
+
+    <build>
+        <plugins>
+
+            <plugin>
+                <!-- This plugin will set properties values using dependency information -->
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-dependency-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <goals>
+                            <!--
+                            Goal that sets a property pointing to the artifact file for each project dependency.
+                            For each dependency (direct and transitive) a project property will be set which
+                            follows the:
+
+                               groupId:artifactId:type:[classifier]
+
+                            form and contains the path to the resolved artifact. -->
+                            <goal>properties</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.6.1</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                    <!-- Uncomment the following line to use the type annotations compiler. -->
+                    <!-- <fork>true</fork> -->
+                    <compilerArguments>
+                        <Xmaxerrs>10000</Xmaxerrs>
+                        <Xmaxwarns>10000</Xmaxwarns>
+                    </compilerArguments>
+                    <annotationProcessors>
+                        <!-- Add all the checkers you want to enable here -->
+                        <annotationProcessor>org.checkerframework.checker.nullness.NullnessChecker</annotationProcessor>
+                        <annotationProcessor>org.checkerframework.checker.interning.InterningChecker</annotationProcessor>
+                        <annotationProcessor>org.checkerframework.checker.fenum.FenumChecker</annotationProcessor>
+                        <annotationProcessor>org.checkerframework.checker.formatter.FormatterChecker</annotationProcessor>
+                        <annotationProcessor>org.checkerframework.checker.regex.RegexChecker</annotationProcessor>
+                    </annotationProcessors>
+                    <compilerArgs>
+                        <arg>-AprintErrorStack</arg>
+
+                        <!-- location of the annotated JDK, which comes from a Maven dependency -->
+                        <arg>-Xbootclasspath/p:${annotatedJdk}</arg>
+                        <!--
+                        -->
+
+                        <!-- Uncomment the following line to use the type annotations compiler. -->
+                        <!--
+                        <arg>-J-Xbootclasspath/p:${typeAnnotationsJavac}</arg>
+                        -->
+                        <!-- Uncomment the following line to turn type-checking warnings into errors. -->
+                        <arg>-Awarns</arg>
+                    </compilerArgs>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/FakeNumExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/FakeNumExample.java
new file mode 100644
index 0000000000..f1769cfdea
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/FakeNumExample.java
@@ -0,0 +1,42 @@
+package com.baeldung.typechecker;
+
+import org.checkerframework.checker.fenum.qual.Fenum;
+
+//@SuppressWarnings("fenum:assignment.type.incompatible")
+public class FakeNumExample {
+
+    // Here we use some String constants to represents countries.
+    static final @Fenum("country") String ITALY = "IT";
+    static final @Fenum("country") String US = "US";
+    static final @Fenum("country") String UNITED_KINGDOM = "UK";
+
+    // Here we use other String constants to represent planets instead.
+    static final @Fenum("planet") String MARS = "Mars";
+    static final @Fenum("planet") String EARTH = "Earth";
+    static final @Fenum("planet") String VENUS = "Venus";
+
+    // Now we write this method and we want to be sure that
+    // the String parameter has a value of a country, not that is just a String.
+    void greetCountries(@Fenum("country") String country) {
+        System.out.println("Hello " + country);
+    }
+
+    // Similarly we're enforcing here that the provided
+    // parameter is a String that represent a planet.
+    void greetPlanets(@Fenum("planet") String planet) {
+        System.out.println("Hello " + planet);
+    }
+
+    public static void main(String[] args) {
+
+        FakeNumExample obj = new FakeNumExample();
+
+        // This will fail because we pass a planet-String to a method that
+        // accept a country-String.
+        obj.greetCountries(MARS);
+
+        // Here the opposite happens.
+        obj.greetPlanets(US);
+    }
+
+}
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/FormatExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/FormatExample.java
new file mode 100644
index 0000000000..2fa53ff2c2
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/FormatExample.java
@@ -0,0 +1,23 @@
+package com.baeldung.typechecker;
+
+public class FormatExample {
+
+    public static void main(String[] args) {
+
+        // Just enabling org.checkerframework.checker.formatter.FormatterChecker
+        // we can be sure at compile time that the format strings we pass to format()
+        // are correct. Normally we would have those errors raised just at runtime.
+        // All those formats are in fact wrong.
+
+        String.format("%y", 7);           // error: invalid format string
+
+        String.format("%d", "a string");  // error: invalid argument type for %d
+
+        String.format("%d %s", 7);        // error: missing argument for %s
+
+        String.format("%d", 7, 3);        // warning: unused argument 3
+
+        String.format("{0}", 7);          // warning: unused argument 7, because {0} is wrong syntax
+    }
+
+}
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/KeyForExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/KeyForExample.java
new file mode 100644
index 0000000000..b3072b72ee
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/KeyForExample.java
@@ -0,0 +1,31 @@
+package com.baeldung.typechecker;
+
+import org.checkerframework.checker.nullness.qual.KeyFor;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class KeyForExample {
+
+    private final Map<String, String> config = new HashMap<>();
+
+    KeyForExample() {
+
+        // Here we initialize a map to store
+        // some config data.
+        config.put("url", "http://1.2.3.4");
+        config.put("name", "foobaz");
+    }
+
+    public void dumpPort() {
+
+        // Here, we want to dump the port value stored in the
+        // config, so we declare that this key has to be
+        // present in the config map.
+        // Obviously that will fail because such key is not present
+        // in the map.
+        @KeyFor("config") String key = "port";
+        System.out.println( config.get(key) );
+    }
+
+}
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/MonotonicNotNullExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/MonotonicNotNullExample.java
new file mode 100644
index 0000000000..c4b9c6afe1
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/MonotonicNotNullExample.java
@@ -0,0 +1,28 @@
+package com.baeldung.typechecker;
+
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
+
+import java.util.Date;
+
+public class MonotonicNotNullExample {
+
+    // The idea is we need this field to be to lazily initialized,
+    // so it starts as null but once it becomes not null
+    // it cannot return null.
+    // In these cases, we can use @MonotonicNonNull
+    @MonotonicNonNull private Date firstCall;
+
+    public Date getFirstCall() {
+        if (firstCall == null) {
+            firstCall = new Date();
+        }
+        return firstCall;
+    }
+
+    public void reset() {
+        // This is reported as error because
+        // we wrongly set the field back to null.
+        firstCall = null;
+    }
+
+}
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/NonNullExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/NonNullExample.java
new file mode 100644
index 0000000000..c929eea23f
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/NonNullExample.java
@@ -0,0 +1,27 @@
+package com.baeldung.typechecker;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+public class NonNullExample {
+
+    // This method's parameter is annotated in order
+    // to tell the pluggable type system that it can never be null.
+    private static int countArgs(@NonNull String[] args) {
+        return args.length;
+    }
+
+    // This method's parameter is annotated in order
+    // to tell the pluggable type system that it may be null.
+    public static void main(@Nullable String[] args) {
+
+        // Here lies a potential error,
+        // because we pass a potential null reference to a method
+        // that does not accept nulls.
+        // The Checker Framework will spot this problem at compile time
+        // instead of runtime.
+        System.out.println(countArgs(args));
+
+    }
+
+}
diff --git a/checker-plugin/src/main/java/com/baeldung/typechecker/RegexExample.java b/checker-plugin/src/main/java/com/baeldung/typechecker/RegexExample.java
new file mode 100644
index 0000000000..9503865214
--- /dev/null
+++ b/checker-plugin/src/main/java/com/baeldung/typechecker/RegexExample.java
@@ -0,0 +1,18 @@
+package com.baeldung.typechecker;
+
+import org.checkerframework.checker.regex.qual.Regex;
+
+public class RegexExample {
+
+    // For some reason we want to be sure that this regex
+    // contains at least one capturing group.
+    // However, we do an error and we forgot to define such
+    // capturing group in it.
+    @Regex(1) private static String findNumbers = "\\d*";
+
+    public static void main(String[] args) {
+        String message = "My phone number is +3911223344.";
+        message.matches(findNumbers);
+    }
+
+}
diff --git a/core-groovy/README.md b/core-groovy/README.md
new file mode 100644
index 0000000000..5954a8ab7e
--- /dev/null
+++ b/core-groovy/README.md
@@ -0,0 +1,4 @@
+# Groovy
+
+## Relevant articles:
+
diff --git a/core-groovy/build.gradle b/core-groovy/build.gradle
new file mode 100644
index 0000000000..b3f33836da
--- /dev/null
+++ b/core-groovy/build.gradle
@@ -0,0 +1,13 @@
+group 'com.baeldung'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'groovy'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    compile 'org.codehaus.groovy:groovy-all:2.5.0-alpha-1'
+    testCompile 'org.spockframework:spock-core:1.1-groovy-2.4'
+}
diff --git a/core-groovy/pom.xml b/core-groovy/pom.xml
new file mode 100644
index 0000000000..961a4ba125
--- /dev/null
+++ b/core-groovy/pom.xml
@@ -0,0 +1,128 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>core-groovy</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <repositories>
+        <repository>
+            <id>central</id>
+            <url>http://jcenter.bintray.com</url>
+        </repository>
+    </repositories>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy</artifactId>
+            <version>2.5.0-alpha-1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy-all</artifactId>
+            <version>2.5.0-alpha-1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy-sql</artifactId>
+            <version>2.5.0-alpha-1</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit.jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.platform</groupId>
+            <artifactId>junit-platform-runner</artifactId>
+            <version>${junit.platform.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hsqldb</groupId>
+            <artifactId>hsqldb</artifactId>
+            <version>2.4.0</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.spockframework</groupId>
+            <artifactId>spock-core</artifactId>
+            <version>1.1-groovy-2.4</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.codehaus.gmavenplus</groupId>
+                <artifactId>gmavenplus-plugin</artifactId>
+                <version>1.6</version>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>addSources</goal>
+                            <goal>addTestSources</goal>
+                            <goal>compile</goal>
+                            <goal>compileTests</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>${maven-surefire-plugin.version}</version>
+            </plugin>
+            <plugin>
+                <artifactId>maven-failsafe-plugin</artifactId>
+                <version>2.19.1</version>
+                <dependencies>
+                    <dependency>
+                        <groupId>org.junit.platform</groupId>
+                        <artifactId>junit-platform-surefire-provider</artifactId>
+                        <version>${junit.platform.version}</version>
+                    </dependency>
+                </dependencies>
+                <executions>
+                    <execution>
+                        <id>junit5</id>
+                        <goals>
+                            <goal>integration-test</goal>
+                            <goal>verify</goal>
+                        </goals>
+                        <configuration>
+                            <includes>
+                                <include>**/*Test5.java</include>
+                            </includes>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <kotlin-maven-plugin.version>1.1.2</kotlin-maven-plugin.version>
+        <kotlin-test-junit.version>1.1.2</kotlin-test-junit.version>
+        <kotlin-stdlib.version>1.1.2</kotlin-stdlib.version>
+        <kotlin-reflect.version>1.1.2</kotlin-reflect.version>
+        <kotlinx.version>0.15</kotlinx.version>
+        <mockito-kotlin.version>1.5.0</mockito-kotlin.version>
+
+        <junit.jupiter.version>5.0.0</junit.jupiter.version>
+        <junit.platform.version>1.0.0</junit.platform.version>
+        <junit.vintage.version>4.12.0</junit.vintage.version>
+        <junit4.version>4.12</junit4.version>
+    </properties>
+</project>
+
diff --git a/core-groovy/src/main/groovy/com/baeldung/json/Account.groovy b/core-groovy/src/main/groovy/com/baeldung/json/Account.groovy
new file mode 100644
index 0000000000..84b294f0bd
--- /dev/null
+++ b/core-groovy/src/main/groovy/com/baeldung/json/Account.groovy
@@ -0,0 +1,7 @@
+package com.baeldung.json
+
+class Account {
+    String id
+    BigDecimal value
+    Date createdAt
+}
\ No newline at end of file
diff --git a/core-groovy/src/main/groovy/com/baeldung/json/JsonParser.groovy b/core-groovy/src/main/groovy/com/baeldung/json/JsonParser.groovy
new file mode 100644
index 0000000000..0d7c451972
--- /dev/null
+++ b/core-groovy/src/main/groovy/com/baeldung/json/JsonParser.groovy
@@ -0,0 +1,36 @@
+package com.baeldung.json
+
+import groovy.json.JsonGenerator
+import groovy.json.JsonOutput
+import groovy.json.JsonParserType
+import groovy.json.JsonSlurper
+
+class JsonParser {
+
+    Account toObject(String json) {
+        JsonSlurper jsonSlurper = new JsonSlurper()
+        jsonSlurper.parseText(json) as Account
+    }
+
+    Account toObjectWithIndexOverlay(String json) {
+        JsonSlurper jsonSlurper = new JsonSlurper(type: JsonParserType.INDEX_OVERLAY)
+        jsonSlurper.parseText(json) as Account
+    }
+
+    String toJson(Account account) {
+        JsonOutput.toJson(account)
+    }
+
+    String toJson(Account account, String dateFormat, String... fieldsToExclude) {
+        JsonGenerator generator = new JsonGenerator.Options()
+                .dateFormat(dateFormat)
+                .excludeFieldsByName(fieldsToExclude)
+                .build()
+        generator.toJson(account)
+    }
+
+    String prettyfy(String json) {
+        JsonOutput.prettyPrint(json)
+    }
+
+}
diff --git a/core-groovy/src/test/groovy/com/baeldung/groovy/sql/SqlTest.groovy b/core-groovy/src/test/groovy/com/baeldung/groovy/sql/SqlTest.groovy
new file mode 100644
index 0000000000..ac96a55773
--- /dev/null
+++ b/core-groovy/src/test/groovy/com/baeldung/groovy/sql/SqlTest.groovy
@@ -0,0 +1,229 @@
+package com.baeldung.groovy.sql
+
+import groovy.sql.GroovyResultSet
+import groovy.sql.GroovyRowResult
+import groovy.sql.Sql
+import groovy.transform.CompileStatic
+import static org.junit.Assert.*
+import org.junit.Test
+
+class SqlTest {
+
+    final Map dbConnParams = [url: 'jdbc:hsqldb:mem:testDB', user: 'sa', password: '', driver: 'org.hsqldb.jdbc.JDBCDriver']
+
+    @Test
+    void whenNewSqlInstance_thenDbIsAccessed() {
+        def sql = Sql.newInstance(dbConnParams)
+        sql.close()
+        sql.close()
+    }
+
+    @Test
+    void whenTableDoesNotExist_thenSelectFails() {
+        try {
+            Sql.withInstance(dbConnParams) { Sql sql ->
+                sql.eachRow('select * from PROJECT') {}
+            }
+
+            fail("An exception should have been thrown")
+        } catch (ignored) {
+            //Ok
+        }
+    }
+
+    @Test
+    void whenTableCreated_thenSelectIsPossible() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            def result = sql.execute 'create table PROJECT_1 (id integer not null, name varchar(50), url varchar(100))'
+
+            assertEquals(0, sql.updateCount)
+            assertFalse(result)
+
+            result = sql.execute('select * from PROJECT_1')
+
+            assertTrue(result)
+        }
+    }
+
+    @Test
+    void whenIdentityColumn_thenInsertReturnsNewId() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_2 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            def ids = sql.executeInsert("INSERT INTO PROJECT_2 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')")
+
+            assertEquals(0, ids[0][0])
+
+            ids = sql.executeInsert("INSERT INTO PROJECT_2 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')")
+
+            assertEquals(1, ids[0][0])
+        }
+    }
+
+    @Test
+    void whenUpdate_thenNumberOfAffectedRows() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_3 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.executeInsert("INSERT INTO PROJECT_3 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')")
+            sql.executeInsert("INSERT INTO PROJECT_3 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')")
+            def count = sql.executeUpdate("UPDATE PROJECT_3 SET URL = 'https://' + URL")
+
+            assertEquals(2, count)
+        }
+    }
+
+    @Test
+    void whenEachRow_thenResultSetHasProperties() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_4 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.executeInsert("INSERT INTO PROJECT_4 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+            sql.executeInsert("INSERT INTO PROJECT_4 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')")
+
+            sql.eachRow("SELECT * FROM PROJECT_4") { GroovyResultSet rs ->
+                assertNotNull(rs.name)
+                assertNotNull(rs.url)
+                assertNotNull(rs[0])
+                assertNotNull(rs[1])
+                assertNotNull(rs[2])
+                assertEquals(rs.name, rs['name'])
+                assertEquals(rs.url, rs['url'])
+            }
+        }
+    }
+
+    @Test
+    void whenPagination_thenSubsetIsReturned() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_5 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.executeInsert("INSERT INTO PROJECT_5 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')")
+            sql.executeInsert("INSERT INTO PROJECT_5 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')")
+            def rows = sql.rows('SELECT * FROM PROJECT_5 ORDER BY NAME', 1, 1)
+
+            assertEquals(1, rows.size())
+            assertEquals('REST with Spring', rows[0].name)
+        }
+    }
+
+    @Test
+    void whenParameters_thenReplacement() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_6 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.execute('INSERT INTO PROJECT_6 (NAME, URL) VALUES (?, ?)', 'tutorials', 'github.com/eugenp/tutorials')
+            sql.execute("INSERT INTO PROJECT_6 (NAME, URL) VALUES (:name, :url)", [name: 'REST with Spring', url: 'github.com/eugenp/REST-With-Spring'])
+
+            def rows = sql.rows("SELECT * FROM PROJECT_6 WHERE NAME = 'tutorials'")
+
+            assertEquals(1, rows.size())
+
+            rows = sql.rows("SELECT * FROM PROJECT_6 WHERE NAME = 'REST with Spring'")
+
+            assertEquals(1, rows.size())
+        }
+    }
+
+    @Test
+    void whenParametersInGString_thenReplacement() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_7 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.execute "INSERT INTO PROJECT_7 (NAME, URL) VALUES (${'tutorials'}, ${'github.com/eugenp/tutorials'})"
+            def name = 'REST with Spring'
+            def url = 'github.com/eugenp/REST-With-Spring'
+            sql.execute "INSERT INTO PROJECT_7 (NAME, URL) VALUES (${name}, ${url})"
+
+            def rows = sql.rows("SELECT * FROM PROJECT_7 WHERE NAME = 'tutorials'")
+
+            assertEquals(1, rows.size())
+
+            rows = sql.rows("SELECT * FROM PROJECT_7 WHERE NAME = 'REST with Spring'")
+
+            assertEquals(1, rows.size())
+        }
+    }
+
+    @Test
+    void whenTransactionRollback_thenNoDataInserted() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.withTransaction {
+                sql.execute 'create table PROJECT_8 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+                sql.executeInsert("INSERT INTO PROJECT_8 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+                sql.executeInsert("INSERT INTO PROJECT_8 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')")
+                sql.rollback()
+
+                def rows = sql.rows("SELECT * FROM PROJECT_8")
+
+                assertEquals(0, rows.size())
+            }
+        }
+    }
+
+    @Test
+    void whenTransactionRollbackThenCommit_thenOnlyLastInserted() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.withTransaction {
+                sql.execute 'create table PROJECT_9 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+                sql.executeInsert("INSERT INTO PROJECT_9 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+                sql.rollback()
+                sql.executeInsert("INSERT INTO PROJECT_9 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')")
+                sql.rollback()
+                sql.executeInsert("INSERT INTO PROJECT_9 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+                sql.executeInsert("INSERT INTO PROJECT_9 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')")
+            }
+
+            def rows = sql.rows("SELECT * FROM PROJECT_9")
+
+            assertEquals(2, rows.size())
+        }
+    }
+
+    @Test
+    void whenException_thenTransactionIsRolledBack() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            try {
+                sql.withTransaction {
+                    sql.execute 'create table PROJECT_10 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+                    sql.executeInsert("INSERT INTO PROJECT_10 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+                    throw new Exception('rollback')
+                }
+            } catch (ignored) {}
+
+            def rows = sql.rows("SELECT * FROM PROJECT_10")
+
+            assertEquals(0, rows.size())
+        }
+    }
+
+    @Test
+    void givenCachedConnection_whenException_thenDataIsPersisted() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            try {
+                sql.cacheConnection {
+                    sql.execute 'create table PROJECT_11 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+                    sql.executeInsert("INSERT INTO PROJECT_11 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')")
+                    throw new Exception('This does not rollback')
+                }
+            } catch (ignored) {}
+
+            def rows = sql.rows("SELECT * FROM PROJECT_11")
+
+            assertEquals(1, rows.size())
+        }
+    }
+
+    /*@Test
+    void whenModifyResultSet_thenDataIsChanged() {
+        Sql.withInstance(dbConnParams) { Sql sql ->
+            sql.execute 'create table PROJECT_5 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))'
+            sql.executeInsert("INSERT INTO PROJECT_5 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')")
+            sql.executeInsert("INSERT INTO PROJECT_5 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')")
+
+            sql.eachRow("SELECT * FROM PROJECT_5 FOR UPDATE ") { GroovyResultSet rs ->
+                rs['name'] = "The great ${rs.name}!" as String
+                rs.updateRow()
+            }
+
+            sql.eachRow("SELECT * FROM PROJECT_5") { GroovyResultSet rs ->
+                assertTrue(rs.name.startsWith('The great '))
+            }
+        }
+    }*/
+
+}
diff --git a/core-groovy/src/test/groovy/com/baeldung/json/JsonParserTest.groovy b/core-groovy/src/test/groovy/com/baeldung/json/JsonParserTest.groovy
new file mode 100644
index 0000000000..fcd51d58bc
--- /dev/null
+++ b/core-groovy/src/test/groovy/com/baeldung/json/JsonParserTest.groovy
@@ -0,0 +1,80 @@
+package com.baeldung.json
+
+import spock.lang.Specification
+
+import java.text.SimpleDateFormat
+
+class JsonParserTest extends Specification {
+
+    JsonParser jsonParser
+
+    void setup () {
+        jsonParser = new JsonParser()
+    }
+
+    def 'Should parse to Account given Json String' () {
+        given:
+            def json = '{"id":"1234","value":15.6}'
+        when:
+            def account = jsonParser.toObject(json)
+        then:
+            account
+            account instanceof Account
+            account.id == '1234'
+            account.value == 15.6
+    }
+
+    def 'Should parse to Account given Json String with date property' () {
+        given:
+            def json = '{"id":"1234","value":15.6,"createdAt":"2018-01-01T00:00:00+0000"}'
+        when:
+            def account = jsonParser.toObjectWithIndexOverlay(json)
+        then:
+            account
+            account instanceof Account
+            account.id == '1234'
+            account.value == 15.6
+            println account.createdAt
+            account.createdAt == Date.parse('yyyy-MM-dd', '2018-01-01')
+    }
+
+    def 'Should parse to Json given an Account object' () {
+        given:
+            Account account = new Account(
+                    id: '123',
+                    value: 15.6,
+                    createdAt: new SimpleDateFormat('MM/dd/yyyy').parse('01/01/2018')
+            )
+        when:
+            def json = jsonParser.toJson(account)
+        then:
+            json
+            json == '{"value":15.6,"createdAt":"2018-01-01T00:00:00+0000","id":"123"}'
+    }
+
+    def 'Should parse to Json given an Account object, a date format and fields to exclude' () {
+        given:
+            Account account = new Account(
+                    id: '123',
+                    value: 15.6,
+                    createdAt: new SimpleDateFormat('MM/dd/yyyy').parse('01/01/2018')
+            )
+        when:
+            def json = jsonParser.toJson(account, 'MM/dd/yyyy', 'value')
+        then:
+            json
+            json == '{"createdAt":"01/01/2018","id":"123"}'
+    }
+
+    def 'Should prettify given a json string' () {
+        given:
+            String json = '{"value":15.6,"createdAt":"01/01/2018","id":"123456"}'
+        when:
+            def jsonPretty = jsonParser.prettyfy(json)
+        then:
+            jsonPretty
+            jsonPretty == '{\n    "value": 15.6,\n    "createdAt": "01/01/2018",\n    "id": "123456"\n}'
+    }
+
+
+}
diff --git a/core-java-8/README.md b/core-java-8/README.md
index 9260e3d447..1b5208961d 100644
--- a/core-java-8/README.md
+++ b/core-java-8/README.md
@@ -40,3 +40,4 @@
 - [Efficient Word Frequency Calculator in Java](http://www.baeldung.com/java-word-frequency)
 - [Primitive Type Streams in Java 8](http://www.baeldung.com/java-8-primitive-streams)
 - [Fail-Safe Iterator vs Fail-Fast Iterator](http://www.baeldung.com/java-fail-safe-vs-fail-fast-iterator)
+- [Shuffling Collections In Java](http://www.baeldung.com/java-shuffle-collection)
diff --git a/core-java-8/src/test/java/com/baeldung/shufflingcollections/ShufflingCollectionsUnitTest.java b/core-java-8/src/test/java/com/baeldung/shufflingcollections/ShufflingCollectionsUnitTest.java
new file mode 100644
index 0000000000..d013907c9a
--- /dev/null
+++ b/core-java-8/src/test/java/com/baeldung/shufflingcollections/ShufflingCollectionsUnitTest.java
@@ -0,0 +1,70 @@
+package com.baeldung.shufflingcollections;
+
+import org.junit.Test;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class ShufflingCollectionsUnitTest {
+
+    @Test
+    public void whenShufflingList_thenListIsShuffled() {
+        List<String> students = Arrays.asList("Foo", "Bar", "Baz", "Qux");
+
+        System.out.println("List before shuffling:");
+        System.out.println(students);
+
+        Collections.shuffle(students);
+        System.out.println("List after shuffling:");
+        System.out.println(students);
+    }
+
+    @Test
+    public void whenShufflingMapEntries_thenValuesAreShuffled() {
+        Map<Integer, String> studentsById = new HashMap<>();
+        studentsById.put(1, "Foo");
+        studentsById.put(2, "Bar");
+        studentsById.put(3, "Baz");
+        studentsById.put(4, "Qux");
+
+        System.out.println("Students before shuffling:");
+        System.out.println(studentsById.values());
+
+        List<Map.Entry<Integer, String>> shuffledStudentEntries = new ArrayList<>(studentsById.entrySet());
+        Collections.shuffle(shuffledStudentEntries);
+
+        List<String> shuffledStudents = shuffledStudentEntries.stream()
+                .map(Map.Entry::getValue)
+                .collect(Collectors.toList());
+
+        System.out.println("Students after shuffling");
+        System.out.println(shuffledStudents);
+    }
+
+    @Test
+    public void whenShufflingSet_thenElementsAreShuffled() {
+        Set<String> students = new HashSet<>(Arrays.asList("Foo", "Bar", "Baz", "Qux"));
+
+        System.out.println("Set before shuffling:");
+        System.out.println(students);
+
+        List<String> studentList = new ArrayList<>(students);
+
+        Collections.shuffle(studentList);
+        System.out.println("Shuffled set elements:");
+        System.out.println(studentList);
+    }
+
+    @Test
+    public void whenShufflingWithSameRandomness_thenElementsAreShuffledDeterministically() {
+        List<String> students_1 = Arrays.asList("Foo", "Bar", "Baz", "Qux");
+        List<String> students_2 = Arrays.asList("Foo", "Bar", "Baz", "Qux");
+
+        Collections.shuffle(students_1, new Random(5));
+        Collections.shuffle(students_2, new Random(5));
+
+        assertThat(students_1).isEqualTo(students_2);
+    }
+}
diff --git a/core-java-9/src/main/java/com/baeldung/java9/methodhandles/Book.java b/core-java-9/src/main/java/com/baeldung/java9/methodhandles/Book.java
new file mode 100644
index 0000000000..479f62cb4e
--- /dev/null
+++ b/core-java-9/src/main/java/com/baeldung/java9/methodhandles/Book.java
@@ -0,0 +1,17 @@
+package com.baeldung.java9.methodhandles;
+
+public class Book {
+
+    String id;
+    String title;
+
+    public Book(String id, String title) {
+        this.id = id;
+        this.title = title;
+    }
+
+    @SuppressWarnings("unused")
+    private String formatBook() {
+        return id + " > " + title;
+    }
+}
diff --git a/core-java-9/src/test/java/com/baeldung/java9/httpclient/SimpleHttpRequestsUnitTest.java b/core-java-9/src/test/java/com/baeldung/java9/httpclient/SimpleHttpRequestsUnitTest.java
deleted file mode 100644
index 4a704139a1..0000000000
--- a/core-java-9/src/test/java/com/baeldung/java9/httpclient/SimpleHttpRequestsUnitTest.java
+++ /dev/null
@@ -1,126 +0,0 @@
-package com.baeldung.java9.httpclient;
-
-import static java.net.HttpURLConnection.HTTP_OK;
-import static org.junit.Assert.assertTrue;
-
-import java.io.IOException;
-import java.net.CookieManager;
-import java.net.CookiePolicy;
-import java.net.URI;
-import java.net.URISyntaxException;
-import java.net.http.HttpClient;
-import java.net.http.HttpHeaders;
-import java.net.http.HttpRequest;
-import java.net.http.HttpResponse;
-import java.security.NoSuchAlgorithmException;
-import java.util.List;
-import java.util.Map;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ExecutionException;
-
-import javax.net.ssl.SSLContext;
-import javax.net.ssl.SSLParameters;
-
-import org.junit.Before;
-import org.junit.Test;
-
-public class SimpleHttpRequestsUnitTest {
-
-    private URI httpURI;
-
-    @Before
-    public void init() throws URISyntaxException {
-        httpURI = new URI("http://www.baeldung.com/");
-    }
-
-    @Test
-    public void quickGet() throws IOException, InterruptedException, URISyntaxException {
-        HttpRequest request = HttpRequest.create(httpURI).GET();
-        HttpResponse response = request.response();
-        int responseStatusCode = response.statusCode();
-        String responseBody = response.body(HttpResponse.asString());
-        assertTrue("Get response status code is bigger then 400", responseStatusCode < 400);
-    }
-
-    @Test
-    public void asynchronousGet() throws URISyntaxException, IOException, InterruptedException, ExecutionException {
-        HttpRequest request = HttpRequest.create(httpURI).GET();
-        long before = System.currentTimeMillis();
-        CompletableFuture<HttpResponse> futureResponse = request.responseAsync();
-        futureResponse.thenAccept(response -> {
-            String responseBody = response.body(HttpResponse.asString());
-        });
-        HttpResponse resp = futureResponse.get();
-        HttpHeaders hs = resp.headers();
-        assertTrue("There should be more then 1 header.", hs.map().size() > 1);
-    }
-
-    @Test
-    public void postMehtod() throws URISyntaxException, IOException, InterruptedException {
-        HttpRequest.Builder requestBuilder = HttpRequest.create(httpURI);
-        requestBuilder.body(HttpRequest.fromString("param1=foo,param2=bar")).followRedirects(HttpClient.Redirect.SECURE);
-        HttpRequest request = requestBuilder.POST();
-        HttpResponse response = request.response();
-        int statusCode = response.statusCode();
-        assertTrue("HTTP return code", statusCode == HTTP_OK);
-    }
-
-    @Test
-    public void configureHttpClient() throws NoSuchAlgorithmException, URISyntaxException, IOException, InterruptedException {
-        CookieManager cManager = new CookieManager();
-        cManager.setCookiePolicy(CookiePolicy.ACCEPT_ORIGINAL_SERVER);
-
-        SSLParameters sslParam = new SSLParameters(new String[] { "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256" }, new String[] { "TLSv1.2" });
-
-        HttpClient.Builder hcBuilder = HttpClient.create();
-        hcBuilder.cookieManager(cManager).sslContext(SSLContext.getDefault()).sslParameters(sslParam);
-        HttpClient httpClient = hcBuilder.build();
-        HttpRequest.Builder reqBuilder = httpClient.request(new URI("https://www.facebook.com"));
-
-        HttpRequest request = reqBuilder.followRedirects(HttpClient.Redirect.ALWAYS).GET();
-        HttpResponse response = request.response();
-        int statusCode = response.statusCode();
-        assertTrue("HTTP return code", statusCode == HTTP_OK);
-    }
-
-    SSLParameters getDefaultSSLParameters() throws NoSuchAlgorithmException {
-        SSLParameters sslP1 = SSLContext.getDefault().getSupportedSSLParameters();
-        String[] proto = sslP1.getApplicationProtocols();
-        String[] cifers = sslP1.getCipherSuites();
-        System.out.println(printStringArr(proto));
-        System.out.println(printStringArr(cifers));
-        return sslP1;
-    }
-
-    String printStringArr(String... args) {
-        if (args == null) {
-            return null;
-        }
-        StringBuilder sb = new StringBuilder();
-        for (String s : args) {
-            sb.append(s);
-            sb.append("\n");
-        }
-        return sb.toString();
-    }
-
-    String printHeaders(HttpHeaders h) {
-        if (h == null) {
-            return null;
-        }
-
-        StringBuilder sb = new StringBuilder();
-        Map<String, List<String>> hMap = h.map();
-        for (String k : hMap.keySet()) {
-            sb.append(k).append(":");
-            List<String> l = hMap.get(k);
-            if (l != null) {
-                l.forEach(s -> {
-                    sb.append(s).append(",");
-                });
-            }
-            sb.append("\n");
-        }
-        return sb.toString();
-    }
-}
diff --git a/core-java-9/src/test/java/com/baeldung/java9/methodhandles/MethodHandlesTest.java b/core-java-9/src/test/java/com/baeldung/java9/methodhandles/MethodHandlesTest.java
new file mode 100644
index 0000000000..7646755358
--- /dev/null
+++ b/core-java-9/src/test/java/com/baeldung/java9/methodhandles/MethodHandlesTest.java
@@ -0,0 +1,152 @@
+package com.baeldung.java9.methodhandles;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.invoke.WrongMethodTypeException;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+
+/**
+ * Test case for the {@link MethodHandles} API
+ */
+public class MethodHandlesTest {
+
+    @Test
+    public void givenConcatMethodHandle_whenInvoked_thenCorrectlyConcatenated() throws Throwable {
+
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(String.class, String.class);
+        MethodHandle concatMH = publicLookup.findVirtual(String.class, "concat", mt);
+
+        String output = (String) concatMH.invoke("Effective ", "Java");
+
+        assertEquals("Effective Java", output);
+    }
+
+    @Test
+    public void givenAsListMethodHandle_whenInvokingWithArguments_thenCorrectlyInvoked() throws Throwable {
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(List.class, Object[].class);
+        MethodHandle asListMH = publicLookup.findStatic(Arrays.class, "asList", mt);
+
+        List<Integer> list = (List<Integer>) asListMH.invokeWithArguments(1, 2);
+
+        assertThat(Arrays.asList(1, 2), is(list));
+    }
+
+    @Test
+    public void givenConstructorMethodHandle_whenInvoked_thenObjectCreatedCorrectly() throws Throwable {
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(void.class, String.class);
+        MethodHandle newIntegerMH = publicLookup.findConstructor(Integer.class, mt);
+
+        Integer integer = (Integer) newIntegerMH.invoke("1");
+
+        assertEquals(1, integer.intValue());
+    }
+
+    @Test
+    public void givenAFieldWithoutGetter_whenCreatingAGetter_thenCorrectlyInvoked() throws Throwable {
+        MethodHandles.Lookup lookup = MethodHandles.lookup();
+        MethodHandle getTitleMH = lookup.findGetter(Book.class, "title", String.class);
+
+        Book book = new Book("ISBN-1234", "Effective Java");
+
+        assertEquals("Effective Java", getTitleMH.invoke(book));
+    }
+
+    @Test
+    public void givenPrivateMethod_whenCreatingItsMethodHandle_thenCorrectlyInvoked() throws Throwable {
+        MethodHandles.Lookup lookup = MethodHandles.lookup();
+        Method formatBookMethod = Book.class.getDeclaredMethod("formatBook");
+        formatBookMethod.setAccessible(true);
+
+        MethodHandle formatBookMH = lookup.unreflect(formatBookMethod);
+
+        Book book = new Book("ISBN-123", "Java in Action");
+
+        assertEquals("ISBN-123 > Java in Action", formatBookMH.invoke(book));
+    }
+
+    @Test
+    public void givenReplaceMethod_whenUsingReflectionAndInvoked_thenCorrectlyReplaced() throws Throwable {
+        Method replaceMethod = String.class.getMethod("replace", char.class, char.class);
+
+        String string = (String) replaceMethod.invoke("jovo", 'o', 'a');
+
+        assertEquals("java", string);
+    }
+
+    @Test
+    public void givenReplaceMethodHandle_whenInvoked_thenCorrectlyReplaced() throws Throwable {
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(String.class, char.class, char.class);
+        MethodHandle replaceMH = publicLookup.findVirtual(String.class, "replace", mt);
+
+        String replacedString = (String) replaceMH.invoke("jovo", Character.valueOf('o'), 'a');
+
+        assertEquals("java", replacedString);
+    }
+
+    @Test
+    public void givenReplaceMethodHandle_whenInvokingExact_thenCorrectlyReplaced() throws Throwable {
+        MethodHandles.Lookup lookup = MethodHandles.lookup();
+        MethodType mt = MethodType.methodType(String.class, char.class, char.class);
+        MethodHandle replaceMH = lookup.findVirtual(String.class, "replace", mt);
+
+        String s = (String) replaceMH.invokeExact("jovo", 'o', 'a');
+
+        assertEquals("java", s);
+    }
+
+    @Test
+    public void givenSumMethodHandle_whenInvokingExact_thenSumIsCorrect() throws Throwable {
+        MethodHandles.Lookup lookup = MethodHandles.lookup();
+        MethodType mt = MethodType.methodType(int.class, int.class, int.class);
+        MethodHandle sumMH = lookup.findStatic(Integer.class, "sum", mt);
+
+        int sum = (int) sumMH.invokeExact(1, 11);
+
+        assertEquals(12, sum);
+    }
+
+    @Test(expected = WrongMethodTypeException.class)
+    public void givenSumMethodHandleAndIncompatibleArguments_whenInvokingExact_thenException() throws Throwable {
+        MethodHandles.Lookup lookup = MethodHandles.lookup();
+        MethodType mt = MethodType.methodType(int.class, int.class, int.class);
+        MethodHandle sumMH = lookup.findStatic(Integer.class, "sum", mt);
+
+        sumMH.invokeExact(Integer.valueOf(1), 11);
+    }
+
+    @Test
+    public void givenSpreadedEqualsMethodHandle_whenInvokedOnArray_thenCorrectlyEvaluated() throws Throwable {
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(boolean.class, Object.class);
+        MethodHandle equalsMH = publicLookup.findVirtual(String.class, "equals", mt);
+
+        MethodHandle methodHandle = equalsMH.asSpreader(Object[].class, 2);
+
+        assertTrue((boolean) methodHandle.invoke(new Object[] { "java", "java" }));
+        assertFalse((boolean) methodHandle.invoke(new Object[] { "java", "jova" }));
+    }
+
+    @Test
+    public void givenConcatMethodHandle_whenBindToAString_thenCorrectlyConcatenated() throws Throwable {
+        MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+        MethodType mt = MethodType.methodType(String.class, String.class);
+        MethodHandle concatMH = publicLookup.findVirtual(String.class, "concat", mt);
+
+        MethodHandle bindedConcatMH = concatMH.bindTo("Hello ");
+
+        assertEquals("Hello World!", bindedConcatMH.invoke("World!"));
+    }
+}
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/BlockedState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/BlockedState.java
new file mode 100644
index 0000000000..19c6d08c2d
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/BlockedState.java
@@ -0,0 +1,31 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class BlockedState {
+    public static void main(String[] args) throws InterruptedException {
+        Thread t1 = new Thread(new DemoThreadB());
+        Thread t2 = new Thread(new DemoThreadB());
+        
+        t1.start();
+        t2.start();
+        
+        Thread.sleep(1000);
+        
+        System.out.println(t2.getState());
+        System.exit(0);
+    }
+}
+
+class DemoThreadB implements Runnable {
+    @Override
+    public void run() {
+        commonResource();
+    }
+    
+    public static synchronized void commonResource() {
+        while(true) {
+            // Infinite loop to mimic heavy processing
+            // Thread 't1' won't leave this method
+            // when Thread 't2' enters this
+        }
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/NewState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/NewState.java
new file mode 100644
index 0000000000..b524cc5ec7
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/NewState.java
@@ -0,0 +1,14 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class NewState implements Runnable {
+    public static void main(String[] args) {
+        Runnable runnable = new NewState();
+        Thread t = new Thread(runnable);
+        System.out.println(t.getState());
+    }
+    
+    @Override
+    public void run() {
+        
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/RunnableState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/RunnableState.java
new file mode 100644
index 0000000000..4aa8b36a76
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/RunnableState.java
@@ -0,0 +1,15 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class RunnableState implements Runnable {
+    public static void main(String[] args) {
+        Runnable runnable = new NewState();
+        Thread t = new Thread(runnable);
+        t.start();
+        System.out.println(t.getState());
+    }
+    
+    @Override
+    public void run() {
+        
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TerminatedState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TerminatedState.java
new file mode 100644
index 0000000000..7c8884dc22
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TerminatedState.java
@@ -0,0 +1,15 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class TerminatedState implements Runnable {
+    public static void main(String[] args) throws InterruptedException {
+        Thread t1 = new Thread(new TerminatedState());
+        t1.start();
+        Thread.sleep(1000);
+        System.out.println(t1.getState());
+    }
+    
+    @Override
+    public void run() {
+        // No processing in this block
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TimedWaitingState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TimedWaitingState.java
new file mode 100644
index 0000000000..8d005352eb
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/TimedWaitingState.java
@@ -0,0 +1,25 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class TimedWaitingState {
+    public static void main(String[] args) throws InterruptedException {
+        DemoThread obj1 = new DemoThread();
+        Thread t1 = new Thread(obj1);
+        t1.start();
+        // The following sleep will give enough time for ThreadScheduler
+        // to start processing of thread t1
+        Thread.sleep(1000);
+        System.out.println(t1.getState());
+    }
+}
+
+class DemoThread implements Runnable {
+    @Override
+    public void run() {
+        try {
+            Thread.sleep(5000);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            e.printStackTrace();
+        }
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/WaitingState.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/WaitingState.java
new file mode 100644
index 0000000000..98a6844309
--- /dev/null
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/threadlifecycle/WaitingState.java
@@ -0,0 +1,35 @@
+package com.baeldung.concurrent.threadlifecycle;
+
+public class WaitingState implements Runnable {
+    public static Thread t1;
+
+    public static void main(String[] args) {
+        t1 = new Thread(new WaitingState());
+        t1.start();
+    }
+
+    public void run() {
+        Thread t2 = new Thread(new DemoThreadWS());
+        t2.start();
+
+        try {
+            t2.join();
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            e.printStackTrace();
+        }
+    }
+}
+
+class DemoThreadWS implements Runnable {
+    public void run() {
+        try {
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            e.printStackTrace();
+        }
+        
+        System.out.println(WaitingState.t1.getState());
+    }
+}
\ No newline at end of file
diff --git a/core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadTest.java b/core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadManualTest.java
similarity index 97%
rename from core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadTest.java
rename to core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadManualTest.java
index af54d6932e..9ea40824ca 100644
--- a/core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadTest.java
+++ b/core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadManualTest.java
@@ -10,7 +10,7 @@ import org.junit.Test;
 
 import com.jayway.awaitility.Awaitility;
 
-public class StopThreadTest {
+public class StopThreadManualTest {
 
     @Test
     public void whenStoppedThreadIsStopped() throws InterruptedException {
diff --git a/core-java/README.md b/core-java/README.md
index ed60db855c..5be4e12592 100644
--- a/core-java/README.md
+++ b/core-java/README.md
@@ -127,3 +127,5 @@
 - [Polymorphism in Java](http://www.baeldung.com/java-polymorphism)
 - [Recursion In Java](http://www.baeldung.com/java-recursion)
 - [A Guide to the finalize Method in Java](http://www.baeldung.com/java-finalize)
+- [Compiling Java *.class Files with javac](http://www.baeldung.com/javac)
+- [Method Overloading and Overriding in Java](http://www.baeldung.com/java-method-overload-override)
diff --git a/core-java/pom.xml b/core-java/pom.xml
index 5c1e9fcad0..e2983de9dd 100644
--- a/core-java/pom.xml
+++ b/core-java/pom.xml
@@ -78,6 +78,11 @@
             <artifactId>jackson-databind</artifactId>
             <version>${jackson.version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>${gson.version}</version>
+        </dependency>
 
         <!-- logging -->
         <dependency>
@@ -468,6 +473,7 @@
     <properties>
         <!-- marshalling -->
         <jackson.version>2.8.5</jackson.version>
+        <gson.version>2.8.2</gson.version>
 
         <!-- logging -->
         <org.slf4j.version>1.7.21</org.slf4j.version>
diff --git a/core-java/src/main/java/com/baeldung/casting/Animal.java b/core-java/src/main/java/com/baeldung/casting/Animal.java
new file mode 100644
index 0000000000..9f31c1dda3
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/casting/Animal.java
@@ -0,0 +1,13 @@
+package com.baeldung.casting;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class Animal {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Animal.class);
+
+    public void eat() {
+        LOGGER.info("animal is eating");
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/casting/AnimalFeeder.java b/core-java/src/main/java/com/baeldung/casting/AnimalFeeder.java
new file mode 100644
index 0000000000..89b972e5c2
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/casting/AnimalFeeder.java
@@ -0,0 +1,23 @@
+package com.baeldung.casting;
+
+import java.util.List;
+
+public class AnimalFeeder {
+
+    public void feed(List<Animal> animals) {
+        animals.forEach(animal -> {
+            animal.eat();
+            if (animal instanceof Cat) {
+                ((Cat) animal).meow();
+            }
+        });
+    }
+
+    public void uncheckedFeed(List<Animal> animals) {
+        animals.forEach(animal -> {
+            animal.eat();
+            ((Cat) animal).meow();
+        });
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/casting/Cat.java b/core-java/src/main/java/com/baeldung/casting/Cat.java
new file mode 100644
index 0000000000..aa9a9a881a
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/casting/Cat.java
@@ -0,0 +1,16 @@
+package com.baeldung.casting;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class Cat extends Animal implements Mew {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Cat.class);
+
+    public void eat() {
+        LOGGER.info("cat is eating");
+    }
+
+    public void meow() {
+        LOGGER.info("meow");
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/casting/Dog.java b/core-java/src/main/java/com/baeldung/casting/Dog.java
new file mode 100644
index 0000000000..763c6b4785
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/casting/Dog.java
@@ -0,0 +1,12 @@
+package com.baeldung.casting;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class Dog extends Animal {
+    private static final Logger LOGGER = LoggerFactory.getLogger(Dog.class);
+
+    public void eat() {
+        LOGGER.info("dog is eating");
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/casting/Mew.java b/core-java/src/main/java/com/baeldung/casting/Mew.java
new file mode 100644
index 0000000000..f3c7324551
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/casting/Mew.java
@@ -0,0 +1,5 @@
+package com.baeldung.casting;
+
+public interface Mew {
+    public void meow();
+}
diff --git a/core-java/src/main/java/com/baeldung/classloader/CustomClassLoader.java b/core-java/src/main/java/com/baeldung/classloader/CustomClassLoader.java
new file mode 100644
index 0000000000..c44e863776
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/classloader/CustomClassLoader.java
@@ -0,0 +1,29 @@
+package com.baeldung.classloader;
+
+import java.io.*;
+
+public class CustomClassLoader extends ClassLoader {
+
+
+    public Class getClass(String name) throws ClassNotFoundException {
+        byte[] b = loadClassFromFile(name);
+        return defineClass(name, b, 0, b.length);
+    }
+
+    private byte[] loadClassFromFile(String fileName)  {
+        InputStream inputStream = getClass().getClassLoader().getResourceAsStream(
+                fileName.replace('.', File.separatorChar) + ".class");
+        byte[] buffer;
+        ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
+        int nextValue = 0;
+        try {
+            while ( (nextValue = inputStream.read()) != -1 ) {
+                byteStream.write(nextValue);
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        buffer = byteStream.toByteArray();
+        return buffer;
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/classloader/PrintClassLoader.java b/core-java/src/main/java/com/baeldung/classloader/PrintClassLoader.java
new file mode 100644
index 0000000000..09ee68bf6e
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/classloader/PrintClassLoader.java
@@ -0,0 +1,22 @@
+package com.baeldung.classloader;
+
+import com.sun.javafx.util.Logging;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.ArrayList;
+
+public class PrintClassLoader {
+
+    public void printClassLoaders() throws ClassNotFoundException {
+
+        System.out.println("Classloader of this class:" + PrintClassLoader.class.getClassLoader());
+        System.out.println("Classloader of Logging:" + Logging.class.getClassLoader());
+        System.out.println("Classloader of ArrayList:" + ArrayList.class.getClassLoader());
+
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/deepcopy/Address.java b/core-java/src/main/java/com/baeldung/deepcopy/Address.java
new file mode 100644
index 0000000000..4e010ea92b
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/deepcopy/Address.java
@@ -0,0 +1,59 @@
+package com.baeldung.deepcopy;
+
+import java.io.Serializable;
+
+public class Address implements Serializable, Cloneable {
+
+    @Override
+    public Object clone() {
+        try {
+            return (Address) super.clone();
+        } catch (CloneNotSupportedException e) {
+            return new Address(this.street, this.getCity(), this.getCountry());
+        }
+    }
+
+    private static final long serialVersionUID = 1740913841244949416L;
+    private String street;
+    private String city;
+
+    private String country;
+
+    public Address(Address that) {
+        this(that.getStreet(), that.getCity(), that.getCountry());
+    }
+
+    public Address(String street, String city, String country) {
+        this.street = street;
+        this.city = city;
+        this.country = country;
+    }
+
+    public Address() {
+    }
+
+    public String getStreet() {
+        return street;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public String getCountry() {
+        return country;
+    }
+
+    public void setStreet(String street) {
+        this.street = street;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+
+    public void setCountry(String country) {
+        this.country = country;
+    }
+}
+
diff --git a/core-java/src/main/java/com/baeldung/deepcopy/User.java b/core-java/src/main/java/com/baeldung/deepcopy/User.java
new file mode 100644
index 0000000000..329cfc6b27
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/deepcopy/User.java
@@ -0,0 +1,48 @@
+package com.baeldung.deepcopy;
+
+import java.io.Serializable;
+
+public class User implements Serializable, Cloneable {
+
+    private static final long serialVersionUID = -3427002229954777557L;
+    private String firstName;
+    private String lastName;
+    private Address address;
+
+    public User(String firstName, String lastName, Address address) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.address = address;
+    }
+
+    public User(User that) {
+        this(that.getFirstName(), that.getLastName(), new Address(that.getAddress()));
+    }
+
+    public User() {
+    }
+
+    @Override
+    public Object clone() {
+        User user;
+        try {
+            user = (User) super.clone();
+        } catch (CloneNotSupportedException e) {
+            user = new User(this.getFirstName(), this.getLastName(), this.getAddress());
+        }
+        user.address = (Address) this.address.clone();
+        return user;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public Address getAddress() {
+        return address;
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProcessor.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProcessor.java
new file mode 100644
index 0000000000..b86a572393
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProcessor.java
@@ -0,0 +1,13 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public abstract class AuthenticationProcessor {
+
+    // next element in chain or responsibility
+    public AuthenticationProcessor nextProcessor;
+    
+    public AuthenticationProcessor(AuthenticationProcessor nextProcessor) {
+        this.nextProcessor = nextProcessor;
+    }
+
+    public abstract boolean isAuthorized(AuthenticationProvider authProvider);
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProvider.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProvider.java
new file mode 100644
index 0000000000..552a7ff6d9
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/AuthenticationProvider.java
@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public interface AuthenticationProvider {
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthAuthenticationProcessor.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthAuthenticationProcessor.java
new file mode 100644
index 0000000000..2e2e51fed2
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthAuthenticationProcessor.java
@@ -0,0 +1,21 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public class OAuthAuthenticationProcessor extends AuthenticationProcessor {
+
+    public OAuthAuthenticationProcessor(AuthenticationProcessor nextProcessor) {
+        super(nextProcessor);
+    }
+
+    @Override
+    public boolean isAuthorized(AuthenticationProvider authProvider) {
+
+        if (authProvider instanceof OAuthTokenProvider) {
+            return Boolean.TRUE;
+        } else if (nextProcessor != null) {
+            return nextProcessor.isAuthorized(authProvider);
+        } else {
+            return Boolean.FALSE;
+        }
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthTokenProvider.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthTokenProvider.java
new file mode 100644
index 0000000000..d4e516053b
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/OAuthTokenProvider.java
@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public class OAuthTokenProvider implements AuthenticationProvider {
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/SamlAuthenticationProvider.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/SamlAuthenticationProvider.java
new file mode 100644
index 0000000000..533b2b4a2d
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/SamlAuthenticationProvider.java
@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public class SamlAuthenticationProvider implements AuthenticationProvider {
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordAuthenticationProcessor.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordAuthenticationProcessor.java
new file mode 100644
index 0000000000..df600c35db
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordAuthenticationProcessor.java
@@ -0,0 +1,20 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public class UsernamePasswordAuthenticationProcessor extends AuthenticationProcessor {
+
+    public UsernamePasswordAuthenticationProcessor(AuthenticationProcessor nextProcessor) {
+        super(nextProcessor);
+    }
+
+    @Override
+    public boolean isAuthorized(AuthenticationProvider authProvider) {
+        if (authProvider instanceof UsernamePasswordProvider) {
+            return Boolean.TRUE;
+        } else if (nextProcessor != null) {
+            return nextProcessor.isAuthorized(authProvider);
+        } else {
+            return Boolean.FALSE;
+        }
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordProvider.java b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordProvider.java
new file mode 100644
index 0000000000..9fbfa7554d
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/chainofresponsibility/UsernamePasswordProvider.java
@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+public class UsernamePasswordProvider implements AuthenticationProvider {
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Car.java b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Car.java
new file mode 100644
index 0000000000..50f62cafaa
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Car.java
@@ -0,0 +1,85 @@
+package com.baeldung.designpatterns.flyweight;
+
+import java.awt.Color;
+
+import javax.annotation.concurrent.Immutable;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Represents a car. This class is immutable.
+ * 
+ * @author Donato Rimenti
+ */
+@Immutable
+public class Car implements Vehicle {
+
+	/**
+	 * Logger.
+	 */
+	private final static Logger LOG = LoggerFactory.getLogger(Car.class);
+
+	/**
+	 * The car's engine.
+	 */
+	private Engine engine;
+
+	/**
+	 * The car's color.
+	 */
+	private Color color;
+
+	/**
+	 * Instantiates a new Car.
+	 *
+	 * @param engine
+	 *            the {@link #engine}
+	 * @param color
+	 *            the {@link #color}
+	 */
+	public Car(Engine engine, Color color) {
+		this.engine = engine;
+		this.color = color;
+
+		// Building a new car is a very expensive operation!
+		try {
+			Thread.sleep(2000);
+		} catch (InterruptedException e) {
+			LOG.error("Error while creating a new car", e);
+		}
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.baeldung.designpatterns.flyweight.Vehicle#start()
+	 */
+	@Override
+	public void start() {
+		LOG.info("Car is starting!");
+		engine.start();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.baeldung.designpatterns.flyweight.Vehicle#stop()
+	 */
+	@Override
+	public void stop() {
+		LOG.info("Car is stopping!");
+		engine.stop();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.baeldung.designpatterns.flyweight.Vehicle#getColor()
+	 */
+	@Override
+	public Color getColor() {
+		return this.color;
+	}
+
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Engine.java b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Engine.java
new file mode 100644
index 0000000000..05d9ca98b8
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Engine.java
@@ -0,0 +1,31 @@
+package com.baeldung.designpatterns.flyweight;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Engine for a vehicle.
+ * 
+ * @author Donato Rimenti
+ */
+public class Engine {
+
+	/**
+	 * Logger.
+	 */
+	private final static Logger LOG = LoggerFactory.getLogger(Engine.class);
+
+	/**
+	 * Starts the engine.
+	 */
+	public void start() {
+		LOG.info("Engine is starting!");
+	}
+
+	/**
+	 * Stops the engine.
+	 */
+	public void stop() {
+		LOG.info("Engine is stopping!");
+	}
+}
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Vehicle.java b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Vehicle.java
new file mode 100644
index 0000000000..c285f9fcff
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/Vehicle.java
@@ -0,0 +1,29 @@
+package com.baeldung.designpatterns.flyweight;
+
+import java.awt.Color;
+
+/**
+ * Interface for a vehicle.
+ * 
+ * @author Donato Rimenti
+ */
+public interface Vehicle {
+
+	/**
+	 * Starts the vehicle.
+	 */
+	public void start();
+
+	/**
+	 * Stops the vehicle.
+	 */
+	public void stop();
+
+	/**
+	 * Gets the color of the vehicle.
+	 * 
+	 * @return the color of the vehicle
+	 */
+	public Color getColor();
+
+}
\ No newline at end of file
diff --git a/core-java/src/main/java/com/baeldung/designpatterns/flyweight/VehicleFactory.java b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/VehicleFactory.java
new file mode 100644
index 0000000000..2854b7dab1
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/designpatterns/flyweight/VehicleFactory.java
@@ -0,0 +1,45 @@
+package com.baeldung.designpatterns.flyweight;
+
+import java.awt.Color;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Factory which implements the Flyweight pattern to return an existing vehicle
+ * if present or a new one otherwise.
+ * 
+ * @author Donato Rimenti
+ */
+public class VehicleFactory {
+
+	/**
+	 * Stores the already created vehicles.
+	 */
+	private static Map<Color, Vehicle> vehiclesCache = new HashMap<Color, Vehicle>();
+
+	/**
+	 * Private constructor to prevent this class instantiation.
+	 */
+	private VehicleFactory() {
+	}
+
+	/**
+	 * Returns a vehicle of the same color passed as argument. If that vehicle
+	 * was already created by this factory, that vehicle is returned, otherwise
+	 * a new one is created and returned.
+	 * 
+	 * @param color
+	 *            the color of the vehicle to return
+	 * @return a vehicle of the specified color
+	 */
+	public static Vehicle createVehicle(Color color) {
+		// Looks for the requested vehicle into the cache.
+		// If the vehicle doesn't exist, a new one is created.
+		Vehicle newVehicle = vehiclesCache.computeIfAbsent(color, newColor -> {
+			// Creates the new car.
+			Engine newEngine = new Engine();
+			return new Car(newEngine, newColor);
+		});
+		return newVehicle;
+	}
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/ArmoredCar.java b/core-java/src/main/java/com/baeldung/inheritance/ArmoredCar.java
new file mode 100644
index 0000000000..b6bb5181b8
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/ArmoredCar.java
@@ -0,0 +1,43 @@
+package com.baeldung.inheritance;
+
+public class ArmoredCar extends Car implements Floatable, Flyable{
+    private int bulletProofWindows;
+    private String model;
+    
+    public void remoteStartCar() {
+        // this vehicle can be started by using a remote control
+    }
+    
+    public String registerModel() {
+        return model;
+    }
+    
+    public String getAValue() {
+        return super.model;   // returns value of model defined in base class Car
+        // return this.model;   // will return value of model defined in ArmoredCar
+        // return model;   // will return value of model defined in ArmoredCar
+    }
+    
+    public static String msg() {
+    	// return super.msg(); // this won't compile.
+    	return "ArmoredCar"; 
+    }
+    
+	@Override
+    public void floatOnWater() {
+        System.out.println("I can float!");
+    }
+    
+	@Override
+    public void fly() {
+        System.out.println("I can fly!");
+    }
+    
+    public void aMethod() {
+        // System.out.println(duration); // Won't compile
+        System.out.println(Floatable.duration); // outputs 10
+        System.out.println(Flyable.duration); // outputs 20
+    }
+    
+    
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/BMW.java b/core-java/src/main/java/com/baeldung/inheritance/BMW.java
new file mode 100644
index 0000000000..8ad3bb683f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/BMW.java
@@ -0,0 +1,12 @@
+package com.baeldung.inheritance;
+
+public class BMW extends Car {
+    public BMW() {
+    	super(5, "BMW");
+    }
+	
+	@Override
+    public String toString() {
+    	return model;
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/Car.java b/core-java/src/main/java/com/baeldung/inheritance/Car.java
new file mode 100644
index 0000000000..21ea9ea569
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/Car.java
@@ -0,0 +1,32 @@
+package com.baeldung.inheritance;
+
+public class Car {
+	private final int DEFAULT_WHEEL_COUNT = 5;
+	private final String DEFAULT_MODEL = "Basic";
+
+	protected int wheels;
+    protected String model;
+    
+    public Car() {
+    	this.wheels = DEFAULT_WHEEL_COUNT;
+    	this.model = DEFAULT_MODEL;
+    }
+    
+    public Car(int wheels, String model) {
+    	this.wheels = wheels;
+    	this.model = model;
+    }
+        
+    public void start() {
+        // Check essential parts
+        // If okay, start.
+    }
+    public static int count = 10;
+    public static String msg() {
+        return "Car";
+    }
+    
+    public String toString() {
+    	return model;
+    } 
+}
\ No newline at end of file
diff --git a/core-java/src/main/java/com/baeldung/inheritance/Employee.java b/core-java/src/main/java/com/baeldung/inheritance/Employee.java
new file mode 100644
index 0000000000..599a1d7331
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/Employee.java
@@ -0,0 +1,15 @@
+package com.baeldung.inheritance;
+
+public class Employee {
+    private String name;
+    private Car car;
+    
+    public Employee(String name, Car car) {
+        this.name = name;
+        this.car = car;
+    }
+    
+    public Car getCar() {
+    	return car;
+    }
+}
\ No newline at end of file
diff --git a/core-java/src/main/java/com/baeldung/inheritance/Floatable.java b/core-java/src/main/java/com/baeldung/inheritance/Floatable.java
new file mode 100644
index 0000000000..c0b456dffb
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/Floatable.java
@@ -0,0 +1,10 @@
+package com.baeldung.inheritance;
+
+public interface Floatable {
+    int duration = 10;
+    void floatOnWater();
+    
+    default void repair() {
+        System.out.println("Repairing Floatable object");   
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/Flyable.java b/core-java/src/main/java/com/baeldung/inheritance/Flyable.java
new file mode 100644
index 0000000000..cb8244cf5b
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/Flyable.java
@@ -0,0 +1,13 @@
+package com.baeldung.inheritance;
+
+public interface Flyable {
+    int duration = 10;
+    void fly();
+    
+    /*
+     * Commented 
+     */
+    //default void repair() {
+    //    System.out.println("Repairing Flyable object"); 
+    //}
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/SpaceCar.java b/core-java/src/main/java/com/baeldung/inheritance/SpaceCar.java
new file mode 100644
index 0000000000..8c23b26da9
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/SpaceCar.java
@@ -0,0 +1,18 @@
+package com.baeldung.inheritance;
+
+public class SpaceCar extends Car implements SpaceTraveller {
+	@Override
+    public void floatOnWater() {
+        System.out.println("SpaceCar floating!");
+    }
+    
+	@Override
+    public void fly() {
+        System.out.println("SpaceCar flying!");
+    }
+    
+	@Override
+    public void remoteControl() {
+        System.out.println("SpaceCar being controlled remotely!");
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/inheritance/SpaceTraveller.java b/core-java/src/main/java/com/baeldung/inheritance/SpaceTraveller.java
new file mode 100644
index 0000000000..9b66441791
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/inheritance/SpaceTraveller.java
@@ -0,0 +1,6 @@
+package com.baeldung.inheritance;
+
+public interface SpaceTraveller extends Floatable, Flyable {
+    int duration = 10;
+    void remoteControl();
+}
\ No newline at end of file
diff --git a/core-java/src/main/java/com/baeldung/java/list/CustomList.java b/core-java/src/main/java/com/baeldung/java/list/CustomList.java
new file mode 100644
index 0000000000..8b91fca32f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/java/list/CustomList.java
@@ -0,0 +1,210 @@
+package com.baeldung.java.list;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+import java.util.ListIterator;
+
+public class CustomList<E> implements List<E> {
+    private Object[] internal = {};
+
+    @Override
+    public boolean isEmpty() {
+        // the first cycle
+        // return true;
+
+        // the second cycle
+        // if (internal.length != 0) {
+        //     return false;
+        // } else {
+        //     return true;
+        // }
+
+        // refactoring
+        return internal.length == 0;
+    }
+
+    @Override
+    public int size() {
+        // the first cycle
+        // if (isEmpty()) {
+        //     return 0;
+        // } else {
+        //     return internal.length;
+        // }
+
+        // refactoring
+        return internal.length;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public E get(int index) {
+        // the first cycle
+        // return (E) internal[0];
+
+        // improvement
+        return (E) internal[index];
+    }
+
+    @Override
+    public boolean add(E element) {
+        // the first cycle
+        // internal = new Object[] { element };
+        // return true;
+
+        // the second cycle
+        Object[] temp = Arrays.copyOf(internal, internal.length + 1);
+        temp[internal.length] = element;
+        internal = temp;
+        return true;
+    }
+
+    @Override
+    public void add(int index, E element) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean addAll(Collection<? extends E> collection) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean addAll(int index, Collection<? extends E> collection) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public E remove(int index) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean remove(Object object) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean removeAll(Collection<?> collection) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean retainAll(Collection<?> collection) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean contains(Object object) {
+        for (Object element : internal) {
+            if (object.equals(element)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public boolean containsAll(Collection<?> collection) {
+        for (Object element : collection)
+            if (!contains(element)) {
+                return false;
+            }
+        return true;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public E set(int index, E element) {
+        E oldElement = (E) internal[index];
+        internal[index] = element;
+        return oldElement;
+    }
+
+    @Override
+    public void clear() {
+        internal = new Object[0];
+    }
+
+    @Override
+    public int indexOf(Object object) {
+        for (int i = 0; i < internal.length; i++) {
+            if (object.equals(internal[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    @Override
+    public int lastIndexOf(Object object) {
+        for (int i = internal.length - 1; i >= 0; i--) {
+            if (object.equals(internal[i])) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public List<E> subList(int fromIndex, int toIndex) {
+        Object[] temp = new Object[toIndex - fromIndex];
+        System.arraycopy(internal, fromIndex, temp, 0, temp.length);
+        return (List<E>) Arrays.asList(temp);
+    }
+
+    @Override
+    public Object[] toArray() {
+        return Arrays.copyOf(internal, internal.length);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T[] toArray(T[] array) {
+        if (array.length < internal.length) {
+            return (T[]) Arrays.copyOf(internal, internal.length, array.getClass());
+        }
+
+        System.arraycopy(internal, 0, array, 0, internal.length);
+        if (array.length > internal.length) {
+            array[internal.length] = null;
+        }
+        return array;
+    }
+
+    @Override
+    public Iterator<E> iterator() {
+        return new CustomIterator();
+    }
+
+    @Override
+    public ListIterator<E> listIterator() {
+        return null;
+    }
+
+    @Override
+    public ListIterator<E> listIterator(int index) {
+        // ignored for brevity
+        return null;
+    }
+
+    private class CustomIterator implements Iterator<E> {
+        int index;
+
+        @Override
+        public boolean hasNext() {
+            return index != internal.length;
+        }
+
+        @SuppressWarnings("unchecked")
+        @Override
+        public E next() {
+            E element = (E) CustomList.this.internal[index];
+            index++;
+            return element;
+        }
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/application/Application.java b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/application/Application.java
new file mode 100644
index 0000000000..6e023e9fa8
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/application/Application.java
@@ -0,0 +1,26 @@
+package com.baeldung.methodoverloadingoverriding.application;
+
+import com.baeldung.methodoverloadingoverriding.model.Car;
+import com.baeldung.methodoverloadingoverriding.model.Vehicle;
+import com.baeldung.methodoverloadingoverriding.util.Multiplier;
+
+public class Application {
+    
+    public static void main(String[] args) {
+        Multiplier multiplier = new Multiplier();
+        System.out.println(multiplier.multiply(10, 10));
+        System.out.println(multiplier.multiply(10, 10, 10));
+        System.out.println(multiplier.multiply(10, 10.5));
+        System.out.println(multiplier.multiply(10.5, 10.5));
+        
+        Vehicle vehicle = new Vehicle();
+        System.out.println(vehicle.accelerate(100));
+        System.out.println(vehicle.run());
+        System.out.println(vehicle.stop());
+        
+        Vehicle car = new Car();
+        System.out.println(car.accelerate(80));
+        System.out.println(car.run());
+        System.out.println(car.stop());
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Car.java b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Car.java
new file mode 100644
index 0000000000..aa5bdcaec9
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Car.java
@@ -0,0 +1,9 @@
+package com.baeldung.methodoverloadingoverriding.model;
+
+public class Car extends Vehicle {
+
+    @Override
+    public String accelerate(long mph) {
+        return "The car accelerates at : " + mph + " MPH.";
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Vehicle.java b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Vehicle.java
new file mode 100644
index 0000000000..eb59e8ca23
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Vehicle.java
@@ -0,0 +1,16 @@
+package com.baeldung.methodoverloadingoverriding.model;
+
+public class Vehicle {
+    
+    public String accelerate(long mph) {
+        return "The vehicle accelerates at : " + mph + " MPH.";
+    }
+    
+    public String stop() {
+        return "The vehicle has stopped.";
+    }
+    
+    public String run() {
+        return "The vehicle is running.";
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/util/Multiplier.java b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/util/Multiplier.java
new file mode 100644
index 0000000000..c43e61c78f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/methodoverloadingoverriding/util/Multiplier.java
@@ -0,0 +1,16 @@
+package com.baeldung.methodoverloadingoverriding.util;
+
+public class Multiplier {
+    
+    public int multiply(int a, int b) {
+        return a * b;
+    }
+    
+    public int multiply(int a, int b, int c) {
+        return a * b * c;
+    }
+    
+    public double multiply(double a, double b) {
+        return a * b;
+    }
+}
diff --git a/core-java/src/main/java/com/baeldung/recursion/BinaryNode.java b/core-java/src/main/java/com/baeldung/recursion/BinaryNode.java
new file mode 100644
index 0000000000..0c3f0ecc40
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/recursion/BinaryNode.java
@@ -0,0 +1,31 @@
+package com.baeldung.recursion;
+
+public class BinaryNode {
+    int value;
+    BinaryNode left;
+    BinaryNode right;
+    
+    public BinaryNode(int value){
+        this.value = value;
+    }
+    
+    public int getValue() {
+        return value;
+    }
+    public void setValue(int value) {
+        this.value = value;
+    }
+    public BinaryNode getLeft() {
+        return left;
+    }
+    public void setLeft(BinaryNode left) {
+        this.left = left;
+    }
+    public BinaryNode getRight() {
+        return right;
+    }
+    public void setRight(BinaryNode right) {
+        this.right = right;
+    }
+    
+}
diff --git a/core-java/src/main/java/com/baeldung/recursion/RecursionExample.java b/core-java/src/main/java/com/baeldung/recursion/RecursionExample.java
new file mode 100644
index 0000000000..649c0e0587
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/recursion/RecursionExample.java
@@ -0,0 +1,64 @@
+package com.baeldung.recursion;
+
+public class RecursionExample {
+    
+    public int sum(int n){
+        if (n >= 1){
+            return sum(n - 1) + n;
+        }
+        return n;
+    }
+    
+    public int tailSum(int currentSum, int n){
+        if (n <= 1) {
+            return currentSum + n;
+        }
+        return tailSum(currentSum + n, n - 1);
+    }
+    
+    public int iterativeSum(int n){
+        int sum = 0;
+        if(n < 0){
+            return -1;
+        }
+        for(int i=0; i<=n; i++){
+            sum += i;
+        }
+        return sum;
+    }
+    
+    public int powerOf10(int n){
+        if (n == 0){
+            return 1;
+        }
+        return powerOf10(n-1)*10;
+    }
+    
+    public int fibonacci(int n){
+        if (n <=1 ){
+            return n;
+        }
+        return fibonacci(n-1) + fibonacci(n-2);
+    }
+    
+    public String toBinary(int n){
+        if (n <= 1 ){
+            return String.valueOf(n);
+        }
+        return toBinary(n / 2) + String.valueOf(n % 2);
+    }
+    
+    public int calculateTreeHeight(BinaryNode root){
+        if (root!= null){
+            if (root.getLeft() != null || root.getRight() != null){
+                return 1 + max(calculateTreeHeight(root.left) , calculateTreeHeight(root.right));
+            }
+        }
+        return 0;
+    }
+    
+    public int max(int a,int b){
+        return a>b ? a:b;
+    }
+    
+}
diff --git a/core-java/src/main/java/com/baeldung/resourcebundle/ExampleControl.java b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleControl.java
new file mode 100644
index 0000000000..88ce36c27f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleControl.java
@@ -0,0 +1,15 @@
+package com.baeldung.resourcebundle;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Locale;
+import java.util.ResourceBundle;
+
+public class ExampleControl extends ResourceBundle.Control {
+
+    @Override
+    public List<Locale> getCandidateLocales(String s, Locale locale) {
+        return Arrays.asList(new Locale("pl", "PL"));
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource.java b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource.java
new file mode 100644
index 0000000000..52ccc80f52
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource.java
@@ -0,0 +1,14 @@
+package com.baeldung.resourcebundle;
+
+import java.util.ListResourceBundle;
+
+public class ExampleResource extends ListResourceBundle {
+
+    @Override
+    protected Object[][] getContents() {
+        return new Object[][] { 
+            { "greeting", "hello" } 
+        };
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl.java b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl.java
new file mode 100644
index 0000000000..7d4f11a5d3
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl.java
@@ -0,0 +1,15 @@
+package com.baeldung.resourcebundle;
+
+import java.util.ListResourceBundle;
+
+public class ExampleResource_pl extends ListResourceBundle {
+
+    @Override
+    protected Object[][] getContents() {
+        return new Object[][] { 
+            { "greeting", "cześć" }, 
+            { "language", "polish" }, 
+        };
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl_PL.java b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl_PL.java
new file mode 100644
index 0000000000..252bfcb9cf
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl_PL.java
@@ -0,0 +1,17 @@
+package com.baeldung.resourcebundle;
+
+import java.math.BigDecimal;
+import java.util.ListResourceBundle;
+
+public class ExampleResource_pl_PL extends ListResourceBundle {
+
+    @Override
+    protected Object[][] getContents() {
+        return new Object[][] { 
+            { "currency", "polish zloty" }, 
+            { "toUsdRate", new BigDecimal("3.401") },
+            { "cities", new String[] { "Warsaw", "Cracow" } } 
+        };
+    }
+
+}
diff --git a/core-java/src/main/java/com/baeldung/string/Palindrome.java b/core-java/src/main/java/com/baeldung/string/Palindrome.java
index 0759787249..97d4d36d07 100644
--- a/core-java/src/main/java/com/baeldung/string/Palindrome.java
+++ b/core-java/src/main/java/com/baeldung/string/Palindrome.java
@@ -5,58 +5,62 @@ import java.util.stream.IntStream;
 public class Palindrome {
 
     public boolean isPalindrome(String text) {
-        text = text.replaceAll("\\s+", "")
-            .toLowerCase();
-        int length = text.length();
+        String clean = text.replaceAll("\\s+", "").toLowerCase();
+        int length = clean.length();
         int forward = 0;
         int backward = length - 1;
-        boolean palindrome = true;
         while (backward > forward) {
-            char forwardChar = text.charAt(forward++);
-            char backwardChar = text.charAt(backward--);
+            char forwardChar = clean.charAt(forward++);
+            char backwardChar = clean.charAt(backward--);
             if (forwardChar != backwardChar)
                 return false;
         }
-        return palindrome;
+        return true;
     }
 
     public boolean isPalindromeReverseTheString(String text) {
-        String reverse = "";
-        text = text.replaceAll("\\s+", "").toLowerCase();
-        char[] plain = text.toCharArray();
+        StringBuilder reverse = new StringBuilder();
+        String clean = text.replaceAll("\\s+", "").toLowerCase();
+        char[] plain = clean.toCharArray();
         for (int i = plain.length - 1; i >= 0; i--)
-            reverse += plain[i];
-        return reverse.equals(text);
+            reverse.append(plain[i]);
+        return (reverse.toString()).equals(clean);
     }
 
     public boolean isPalindromeUsingStringBuilder(String text) {
-        StringBuilder plain = new StringBuilder(text);
+        String clean = text.replaceAll("\\s+", "").toLowerCase();
+        StringBuilder plain = new StringBuilder(clean);
         StringBuilder reverse = plain.reverse();
-        return reverse.equals(plain);
+        return (reverse.toString()).equals(clean);
     }
 
     public boolean isPalindromeUsingStringBuffer(String text) {
-        StringBuffer plain = new StringBuffer(text);
+        String clean = text.replaceAll("\\s+", "").toLowerCase();
+        StringBuffer plain = new StringBuffer(clean);
         StringBuffer reverse = plain.reverse();
-        return reverse.equals(plain);
+        return (reverse.toString()).equals(clean);
     }
 
-    public boolean isPalindromeRecursive(String text, int forward, int backward) {
+    public boolean isPalindromeRecursive(String text) {
+        String clean = text.replaceAll("\\s+", "").toLowerCase();
+        return recursivePalindrome(clean, 0, clean.length() - 1);
+    }
+
+    private boolean recursivePalindrome(String text, int forward, int backward) {
         if (forward == backward)
             return true;
         if ((text.charAt(forward)) != (text.charAt(backward)))
             return false;
         if (forward < backward + 1) {
-            return isPalindromeRecursive(text, forward + 1, backward - 1);
+            return recursivePalindrome(text, forward + 1, backward - 1);
         }
 
         return true;
     }
-    
+
     public boolean isPalindromeUsingIntStream(String text) {
-        String temp  = text.replaceAll("\\s+", "").toLowerCase();
+        String temp = text.replaceAll("\\s+", "").toLowerCase();
         return IntStream.range(0, temp.length() / 2)
             .noneMatch(i -> temp.charAt(i) != temp.charAt(temp.length() - i - 1));
     }
-    
 }
diff --git a/core-java/src/main/java/com/baeldung/system/DetectOS.java b/core-java/src/main/java/com/baeldung/system/DetectOS.java
new file mode 100644
index 0000000000..2d605fe49f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/system/DetectOS.java
@@ -0,0 +1,18 @@
+package com.baeldung.system;
+
+import org.apache.commons.lang3.SystemUtils;
+
+public class DetectOS {
+
+    public String getOperatingSystem() {
+        String os = System.getProperty("os.name");
+        System.out.println("Using System Property: " + os);
+        return os;
+    }
+
+    public String getOperatingSystemSystemUtils() {
+        String os = SystemUtils.OS_NAME;
+        System.out.println("Using SystemUtils: " + os);
+        return os;
+    }
+}
diff --git a/core-java/src/main/resources/resourcebundle/resource.properties b/core-java/src/main/resources/resourcebundle/resource.properties
new file mode 100644
index 0000000000..edeae3ef4b
--- /dev/null
+++ b/core-java/src/main/resources/resourcebundle/resource.properties
@@ -0,0 +1,6 @@
+# Buttons
+cancelButton=cancel
+continueButton continue
+
+! Labels
+helloLabel:hello
diff --git a/core-java/src/main/resources/resourcebundle/resource_en.properties b/core-java/src/main/resources/resourcebundle/resource_en.properties
new file mode 100644
index 0000000000..5d72b65e2f
--- /dev/null
+++ b/core-java/src/main/resources/resourcebundle/resource_en.properties
@@ -0,0 +1 @@
+deleteButton=delete
\ No newline at end of file
diff --git a/core-java/src/main/resources/resourcebundle/resource_pl_PL.properties b/core-java/src/main/resources/resourcebundle/resource_pl_PL.properties
new file mode 100644
index 0000000000..37dea822ad
--- /dev/null
+++ b/core-java/src/main/resources/resourcebundle/resource_pl_PL.properties
@@ -0,0 +1,3 @@
+backButton=cofnij
+helloLabel=cze\u015b\u0107
+helloLabelNoEncoding=cześć
\ No newline at end of file
diff --git a/core-java/src/test/java/com/baeldung/casting/CastingTest.java b/core-java/src/test/java/com/baeldung/casting/CastingTest.java
new file mode 100644
index 0000000000..0ca1ce88dc
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/casting/CastingTest.java
@@ -0,0 +1,58 @@
+package com.baeldung.casting;
+
+import org.junit.Test;
+import static org.junit.Assert.*;
+import java.util.ArrayList;
+import java.util.List;
+
+public class CastingTest {
+
+    @Test
+    public void whenPrimitiveConverted_thenValueChanged() {
+        double myDouble = 1.1;
+        int myInt = (int) myDouble;
+        assertNotEquals(myDouble, myInt);
+    }
+
+    @Test
+    public void whenUpcast_thenInstanceUnchanged() {
+        Cat cat = new Cat();
+        Animal animal = cat;
+        animal = (Animal) cat;
+        assertTrue(animal instanceof Cat);
+    }
+
+    @Test
+    public void whenUpcastToObject_thenInstanceUnchanged() {
+        Object object = new Animal();
+        assertTrue(object instanceof Animal);
+    }
+
+    @Test
+    public void whenUpcastToInterface_thenInstanceUnchanged() {
+        Mew mew = new Cat();
+        assertTrue(mew instanceof Cat);
+    }
+
+    @Test
+    public void whenUpcastToAnimal_thenOverridenMethodsCalled() {
+        List<Animal> animals = new ArrayList<>();
+        animals.add(new Cat());
+        animals.add(new Dog());
+        new AnimalFeeder().feed(animals);
+    }
+
+    @Test
+    public void whenDowncastToCat_thenMeowIsCalled() {
+        Animal animal = new Cat();
+        ((Cat) animal).meow();
+    }
+
+    @Test(expected = ClassCastException.class)
+    public void whenDownCastWithoutCheck_thenExceptionThrown() {
+        List<Animal> animals = new ArrayList<>();
+        animals.add(new Cat());
+        animals.add(new Dog());
+        new AnimalFeeder().uncheckedFeed(animals);
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/classloader/CustomClassLoaderTest.java b/core-java/src/test/java/com/baeldung/classloader/CustomClassLoaderTest.java
new file mode 100644
index 0000000000..9f3c751805
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/classloader/CustomClassLoaderTest.java
@@ -0,0 +1,23 @@
+package com.baeldung.classloader;
+
+import org.junit.Test;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+public class CustomClassLoaderTest {
+
+    @Test
+    public void customLoader() throws ClassNotFoundException, IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
+
+        CustomClassLoader customClassLoader = new CustomClassLoader();
+        Class<?> c = customClassLoader.getClass(PrintClassLoader.class.getName());
+
+        Object ob = c.newInstance();
+
+        Method md = c.getMethod("printClassLoaders");
+        md.invoke(ob);
+
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/classloader/PrintClassLoaderTest.java b/core-java/src/test/java/com/baeldung/classloader/PrintClassLoaderTest.java
new file mode 100644
index 0000000000..f44a5cef09
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/classloader/PrintClassLoaderTest.java
@@ -0,0 +1,14 @@
+package com.baeldung.classloader;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class PrintClassLoaderTest {
+    @Test(expected = ClassNotFoundException.class)
+    public void givenAppClassLoader_whenParentClassLoader_thenClassNotFoundException() throws Exception {
+        PrintClassLoader sampleClassLoader = (PrintClassLoader) Class.forName(PrintClassLoader.class.getName()).newInstance();
+        sampleClassLoader.printClassLoaders();
+        Class.forName(PrintClassLoader.class.getName(), true, PrintClassLoader.class.getClassLoader().getParent());
+    }
+}
\ No newline at end of file
diff --git a/core-java/src/test/java/com/baeldung/decimalformat/DecimalFormatExamplesTest.java b/core-java/src/test/java/com/baeldung/decimalformat/DecimalFormatExamplesTest.java
new file mode 100644
index 0000000000..8acd4e023e
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/decimalformat/DecimalFormatExamplesTest.java
@@ -0,0 +1,116 @@
+package com.baeldung.decimalformat;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.math.BigDecimal;
+import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
+import java.text.NumberFormat;
+import java.text.ParseException;
+import java.util.Locale;
+
+import org.junit.Test;
+
+public class DecimalFormatExamplesTest {
+
+	double d = 1234567.89;
+
+	@Test
+	public void givenSimpleDecimal_WhenFormatting_ThenCorrectOutput() {
+
+		assertThat(new DecimalFormat("#.##", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1234567.89");
+
+		assertThat(new DecimalFormat("0.00", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1234567.89");
+
+		assertThat(new DecimalFormat("#########.###", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1234567.89");
+
+		assertThat(new DecimalFormat("000000000.000", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("001234567.890");
+
+	}
+
+	@Test
+	public void givenSmallerDecimalPattern_WhenFormatting_ThenRounding() {
+
+		assertThat(new DecimalFormat("#.#", new DecimalFormatSymbols(Locale.ENGLISH)).format(d)).isEqualTo("1234567.9");
+
+		assertThat(new DecimalFormat("#", new DecimalFormatSymbols(Locale.ENGLISH)).format(d)).isEqualTo("1234568");
+
+	}
+
+	@Test
+	public void givenGroupingSeparator_WhenFormatting_ThenGroupedOutput() {
+
+		assertThat(new DecimalFormat("#,###.#", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1,234,567.9");
+
+		assertThat(new DecimalFormat("#,###", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1,234,568");
+
+	}
+
+	@Test
+	public void givenMixedPattern_WhenFormatting_ThenCorrectOutput() {
+
+		assertThat(new DecimalFormat("The # number", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("The 1234568 number");
+
+		assertThat(new DecimalFormat("The '#' # number", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("The # 1234568 number");
+
+	}
+
+	@Test
+	public void givenLocales_WhenFormatting_ThenCorrectOutput() {
+
+		assertThat(new DecimalFormat("#,###.##", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1,234,567.89");
+
+		assertThat(new DecimalFormat("#,###.##", new DecimalFormatSymbols(Locale.ITALIAN)).format(d))
+				.isEqualTo("1.234.567,89");
+
+		assertThat(new DecimalFormat("#,###.##", DecimalFormatSymbols.getInstance(new Locale("it", "IT"))).format(d))
+				.isEqualTo("1.234.567,89");
+
+	}
+
+	@Test
+	public void givenE_WhenFormatting_ThenScientificNotation() {
+
+		assertThat(new DecimalFormat("00.#######E0", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("12.3456789E5");
+
+		assertThat(new DecimalFormat("000.000000E0", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("123.456789E4");
+
+		assertThat(new DecimalFormat("##0.######E0", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1.23456789E6");
+
+		assertThat(new DecimalFormat("###.000000E0", new DecimalFormatSymbols(Locale.ENGLISH)).format(d))
+				.isEqualTo("1.23456789E6");
+
+	}
+
+	@Test
+	public void givenString_WhenParsing_ThenCorrectOutput() throws ParseException {
+
+		assertThat(new DecimalFormat("", new DecimalFormatSymbols(Locale.ENGLISH)).parse("1234567.89"))
+				.isEqualTo(1234567.89);
+
+		assertThat(new DecimalFormat("", new DecimalFormatSymbols(Locale.ITALIAN)).parse("1.234.567,89"))
+				.isEqualTo(1234567.89);
+
+	}
+
+	@Test
+	public void givenStringAndBigDecimalFlag_WhenParsing_ThenCorrectOutput() throws ParseException {
+
+		NumberFormat nf = new DecimalFormat("", new DecimalFormatSymbols(Locale.ENGLISH));
+		((DecimalFormat) nf).setParseBigDecimal(true);
+		assertThat(nf.parse("1234567.89")).isEqualTo(BigDecimal.valueOf(1234567.89));
+	}
+
+}
diff --git a/core-java/src/test/java/com/baeldung/deepcopy/DeepCopyUnitTest.java b/core-java/src/test/java/com/baeldung/deepcopy/DeepCopyUnitTest.java
new file mode 100644
index 0000000000..196b69fbf7
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/deepcopy/DeepCopyUnitTest.java
@@ -0,0 +1,128 @@
+package com.baeldung.deepcopy;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.io.IOException;
+
+import org.apache.commons.lang.SerializationUtils;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.gson.Gson;
+
+public class DeepCopyUnitTest {
+
+    @Test
+    public void whenCreatingDeepCopyWithCopyConstructor_thenObjectsShouldNotBeSame() {
+
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+
+        User deepCopy = new User(pm);
+
+        assertThat(deepCopy).isNotSameAs(pm);
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenConstructorCopyShouldNotChange() {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        User deepCopy = new User(pm);
+
+        address.setCountry("Great Britain");
+
+        assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenCloneCopyShouldNotChange() {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        User deepCopy = (User) pm.clone();
+
+        address.setCountry("Great Britain");
+
+        assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenCommonsCloneShouldNotChange() {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        User deepCopy = (User) SerializationUtils.clone(pm);
+
+        address.setCountry("Great Britain");
+
+        assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenGsonCloneShouldNotChange() {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        Gson gson = new Gson();
+        User deepCopy = gson.fromJson(gson.toJson(pm), User.class);
+
+        address.setCountry("Great Britain");
+
+        assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenJacksonCopyShouldNotChange() throws IOException {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        ObjectMapper objectMapper = new ObjectMapper();
+        User deepCopy = objectMapper.readValue(objectMapper.writeValueAsString(pm), User.class);
+
+        address.setCountry("Great Britain");
+
+        assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
+    }
+
+    @Test
+    @Ignore
+    public void whenMakingCopies_thenShowHowLongEachMethodTakes() throws CloneNotSupportedException, IOException {
+        int times = 1000000;
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+
+        long start = System.currentTimeMillis();
+        for (int i = 0; i < times; i++) {
+            User primeMinisterClone = (User) SerializationUtils.clone(pm);
+        }
+        long end = System.currentTimeMillis();
+        System.out.println("Cloning with Apache Commons Lang took " + (end - start) + " milliseconds.");
+
+        start = System.currentTimeMillis();
+        Gson gson = new Gson();
+        for (int i = 0; i < times; i++) {
+            User primeMinisterClone = gson.fromJson(gson.toJson(pm), User.class);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("Cloning with Gson took " + (end - start) + " milliseconds.");
+
+        start = System.currentTimeMillis();
+        for (int i = 0; i < times; i++) {
+            User primeMinisterClone = new User(pm);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("Cloning with the copy constructor took " + (end - start) + " milliseconds.");
+
+        start = System.currentTimeMillis();
+        for (int i = 0; i < times; i++) {
+            User primeMinisterClone = (User) pm.clone();
+        }
+        end = System.currentTimeMillis();
+        System.out.println("Cloning with Cloneable interface took " + (end - start) + " milliseconds.");
+
+        start = System.currentTimeMillis();
+        ObjectMapper objectMapper = new ObjectMapper();
+        for (int i = 0; i < times; i++) {
+            User primeMinisterClone = objectMapper.readValue(objectMapper.writeValueAsString(pm), User.class);
+        }
+        end = System.currentTimeMillis();
+        System.out.println("Cloning with Jackson took " + (end - start) + " milliseconds.");
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/deepcopy/ShallowCopyUnitTest.java b/core-java/src/test/java/com/baeldung/deepcopy/ShallowCopyUnitTest.java
new file mode 100644
index 0000000000..57660fadf1
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/deepcopy/ShallowCopyUnitTest.java
@@ -0,0 +1,33 @@
+package com.baeldung.deepcopy;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.Test;
+
+public class ShallowCopyUnitTest {
+
+
+    @Test
+    public void whenShallowCopying_thenObjectsShouldNotBeSame() {
+
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+
+        User shallowCopy = new User(pm.getFirstName(), pm.getLastName(), pm.getAddress());
+
+        assertThat(shallowCopy)
+                .isNotSameAs(pm);
+    }
+
+    @Test
+    public void whenModifyingOriginalObject_thenCopyShouldChange() {
+        Address address = new Address("Downing St 10", "London", "England");
+        User pm = new User("Prime", "Minister", address);
+        User shallowCopy = new User(pm.getFirstName(), pm.getLastName(), pm.getAddress());
+
+        address.setCountry("Great Britain");
+        
+        assertThat(shallowCopy.getAddress().getCountry())
+                .isEqualTo(pm.getAddress().getCountry());
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/designpatterns/chainofresponsibility/ChainOfResponsibilityTest.java b/core-java/src/test/java/com/baeldung/designpatterns/chainofresponsibility/ChainOfResponsibilityTest.java
new file mode 100644
index 0000000000..a28577efb1
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/designpatterns/chainofresponsibility/ChainOfResponsibilityTest.java
@@ -0,0 +1,37 @@
+package com.baeldung.designpatterns.chainofresponsibility;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+
+public class ChainOfResponsibilityTest {
+
+    private static AuthenticationProcessor getChainOfAuthProcessor() {
+
+        AuthenticationProcessor oAuthProcessor = new OAuthAuthenticationProcessor(null);
+        AuthenticationProcessor unamePasswordProcessor = new UsernamePasswordAuthenticationProcessor(oAuthProcessor);
+        return unamePasswordProcessor;
+    }
+
+    @Test
+    public void givenOAuthProvider_whenCheckingAuthorized_thenSuccess() {
+        AuthenticationProcessor authProcessorChain = getChainOfAuthProcessor();
+        boolean isAuthorized = authProcessorChain.isAuthorized(new OAuthTokenProvider());
+        assertTrue(isAuthorized);
+    }
+
+    @Test
+    public void givenUsernamePasswordProvider_whenCheckingAuthorized_thenSuccess() {
+        AuthenticationProcessor authProcessorChain = getChainOfAuthProcessor();
+        boolean isAuthorized = authProcessorChain.isAuthorized(new UsernamePasswordProvider());
+        assertTrue(isAuthorized);
+    }
+
+    @Test
+    public void givenSamlAuthProvider_whenCheckingAuthorized_thenFailure() {
+        AuthenticationProcessor authProcessorChain = getChainOfAuthProcessor();
+        boolean isAuthorized = authProcessorChain.isAuthorized(new SamlAuthenticationProvider());
+        assertTrue(!isAuthorized);
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/designpatterns/flyweight/FlyweightUnitTest.java b/core-java/src/test/java/com/baeldung/designpatterns/flyweight/FlyweightUnitTest.java
new file mode 100644
index 0000000000..645e2fd459
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/designpatterns/flyweight/FlyweightUnitTest.java
@@ -0,0 +1,42 @@
+package com.baeldung.designpatterns.flyweight;
+
+import java.awt.Color;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * Unit test for {@link VehicleFactory}.
+ * 
+ * @author Donato Rimenti
+ */
+public class FlyweightUnitTest {
+
+	/**
+	 * Checks that when the {@link VehicleFactory} is asked to provide two
+	 * vehicles of different colors, the objects returned are different.
+	 */
+	@Test
+	public void givenDifferentFlyweightObjects_whenEquals_thenFalse() {
+		Vehicle blackVehicle = VehicleFactory.createVehicle(Color.BLACK);
+		Vehicle blueVehicle = VehicleFactory.createVehicle(Color.BLUE);
+
+		Assert.assertNotNull("Object returned by the factory is null!", blackVehicle);
+		Assert.assertNotNull("Object returned by the factory is null!", blueVehicle);
+		Assert.assertNotEquals("Objects returned by the factory are equals!", blackVehicle, blueVehicle);
+	}
+
+	/**
+	 * Checks that when the {@link VehicleFactory} is asked to provide two
+	 * vehicles of the same colors, the same object is returned twice.
+	 */
+	@Test
+	public void givenSameFlyweightObjects_whenEquals_thenTrue() {
+		Vehicle blackVehicle = VehicleFactory.createVehicle(Color.BLACK);
+		Vehicle anotherBlackVehicle = VehicleFactory.createVehicle(Color.BLACK);
+
+		Assert.assertNotNull("Object returned by the factory is null!", blackVehicle);
+		Assert.assertNotNull("Object returned by the factory is null!", anotherBlackVehicle);
+		Assert.assertEquals("Objects returned by the factory are not equals!", blackVehicle, anotherBlackVehicle);
+	}
+}
diff --git a/core-java/src/test/java/com/baeldung/inheritance/AppTest.java b/core-java/src/test/java/com/baeldung/inheritance/AppTest.java
new file mode 100644
index 0000000000..1235761aba
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/inheritance/AppTest.java
@@ -0,0 +1,46 @@
+package com.baeldung.inheritance;
+
+import com.baeldung.inheritance.*;
+
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+
+public class AppTest extends TestCase {
+    
+	public AppTest(String testName) {
+        super( testName );
+    }
+
+    public static Test suite() {
+        return new TestSuite(AppTest.class);
+    }
+
+    @SuppressWarnings("static-access")
+	public void testStaticMethodUsingBaseClassVariable() {
+    	Car first = new ArmoredCar();
+    	assertEquals("Car", first.msg());
+    }
+    	
+    @SuppressWarnings("static-access")
+	public void testStaticMethodUsingDerivedClassVariable() {
+    	ArmoredCar second = new ArmoredCar();
+    	assertEquals("ArmoredCar", second.msg());
+    }
+    
+    public void testAssignArmoredCarToCar() {
+    	Employee e1 = new Employee("Shreya", new ArmoredCar());
+    	assertNotNull(e1.getCar());
+    }
+
+    public void testAssignSpaceCarToCar() {
+    	Employee e2 = new Employee("Paul", new SpaceCar());
+    	assertNotNull(e2.getCar());
+    }
+
+    public void testBMWToCar() {
+    	Employee e3 = new Employee("Pavni", new BMW());
+    	assertNotNull(e3.getCar());
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/java/list/CustomListUnitTest.java b/core-java/src/test/java/com/baeldung/java/list/CustomListUnitTest.java
new file mode 100644
index 0000000000..9ea42e88e8
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/java/list/CustomListUnitTest.java
@@ -0,0 +1,296 @@
+package com.baeldung.java.list;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+
+import org.junit.Test;
+
+public class CustomListUnitTest {
+     @Test
+     public void givenEmptyList_whenIsEmpty_thenTrueIsReturned() {
+         List<Object> list = new CustomList<>();
+    
+         assertTrue(list.isEmpty());
+     }
+     
+     @Test
+     public void givenNonEmptyList_whenIsEmpty_thenFalseIsReturned() {
+         List<Object> list = new CustomList<>();
+         list.add(null);
+      
+         assertFalse(list.isEmpty());
+     }
+     
+     @Test
+     public void givenListWithAnElement_whenSize_thenOneIsReturned() {
+         List<Object> list = new CustomList<>();
+         list.add(null);
+      
+         assertEquals(1, list.size());
+     }
+     
+     @Test
+     public void givenListWithAnElement_whenGet_thenThatElementIsReturned() {
+         List<Object> list = new CustomList<>();
+         list.add("baeldung");
+         Object element = list.get(0);
+      
+         assertEquals("baeldung", element);
+     }
+     
+     @Test
+     public void givenEmptyList_whenElementIsAdded_thenGetReturnsThatElement() {
+         List<Object> list = new CustomList<>();
+         boolean succeeded = list.add(null);
+      
+         assertTrue(succeeded);
+     }
+     
+     @Test
+     public void givenListWithAnElement_whenAnotherIsAdded_thenGetReturnsBoth() {
+         List<Object> list = new CustomList<>();
+         list.add("baeldung");
+         list.add(".com");
+         Object element1 = list.get(0);
+         Object element2 = list.get(1);
+
+         assertEquals("baeldung", element1);
+         assertEquals(".com", element2);
+     }
+    
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenAddToSpecifiedIndex_thenExceptionIsThrown() {
+        new CustomList<>().add(0, null);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenAddAllToTheEnd_thenExceptionIsThrown() {
+        Collection<Object> collection = new ArrayList<>();
+        List<Object> list = new CustomList<>();
+        list.addAll(collection);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenAddAllToSpecifiedIndex_thenExceptionIsThrown() {
+        Collection<Object> collection = new ArrayList<>();
+        List<Object> list = new CustomList<>();
+        list.addAll(0, collection);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenRemoveAtSpecifiedIndex_thenExceptionIsThrown() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.remove(0);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenRemoveSpecifiedElement_thenExceptionIsThrown() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.remove("baeldung");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenRemoveAll_thenExceptionIsThrown() {
+        Collection<Object> collection = new ArrayList<>();
+        collection.add("baeldung");
+        List<Object> list = new CustomList<>();
+        list.removeAll(collection);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenRetainAll_thenExceptionIsThrown() {
+        Collection<Object> collection = new ArrayList<>();
+        collection.add("baeldung");
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.retainAll(collection);
+    }
+
+    @Test
+    public void givenEmptyList_whenContains_thenFalseIsReturned() {
+        List<Object> list = new CustomList<>();
+
+        assertFalse(list.contains(null));
+    }
+
+    @Test
+    public void givenListWithAnElement_whenContains_thenTrueIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+
+        assertTrue(list.contains("baeldung"));
+    }
+
+    @Test
+    public void givenListWithAnElement_whenContainsAll_thenTrueIsReturned() {
+        Collection<Object> collection = new ArrayList<>();
+        collection.add("baeldung");
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+
+        assertTrue(list.containsAll(collection));
+    }
+
+    @Test
+    public void givenList_whenContainsAll_thenEitherTrueOrFalseIsReturned() {
+        Collection<Object> collection1 = new ArrayList<>();
+        collection1.add("baeldung");
+        collection1.add(".com");
+        Collection<Object> collection2 = new ArrayList<>();
+        collection2.add("baeldung");
+
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+
+        assertFalse(list.containsAll(collection1));
+        assertTrue(list.containsAll(collection2));
+    }
+
+    @Test
+    public void givenList_whenSet_thenOldElementIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        Object element = list.set(0, null);
+
+        assertEquals("baeldung", element);
+        assertNull(list.get(0));
+    }
+
+    @Test
+    public void givenList_whenClear_thenAllElementsAreRemoved() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.clear();
+
+        assertTrue(list.isEmpty());
+    }
+
+    @Test
+    public void givenList_whenIndexOf_thenIndexZeroIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+
+        assertEquals(0, list.indexOf("baeldung"));
+    }
+
+    @Test
+    public void givenList_whenIndexOf_thenPositiveIndexOrMinusOneIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.add(".com");
+        list.add(".com");
+
+        assertEquals(1, list.indexOf(".com"));
+        assertEquals(-1, list.indexOf("com"));
+    }
+
+    @Test
+    public void whenLastIndexOf_thenIndexZeroIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+
+        assertEquals(0, list.lastIndexOf("baeldung"));
+    }
+
+    @Test
+    public void whenLastIndexOf_thenPositiveIndexOrMinusOneIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.add("baeldung");
+        list.add(".com");
+
+        assertEquals(1, list.lastIndexOf("baeldung"));
+        assertEquals(-1, list.indexOf("com"));
+    }
+
+    @Test
+    public void whenSubListZeroToOne_thenListContainingFirstElementIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        List<Object> subList = list.subList(0, 1);
+
+        assertEquals("baeldung", subList.get(0));
+    }
+
+    @Test
+    public void whenSubListOneToTwo_thenListContainingSecondElementIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.add(".");
+        list.add("com");
+        List<Object> subList = list.subList(1, 2);
+
+        assertEquals(1, subList.size());
+        assertEquals(".", subList.get(0));
+    }
+
+    @Test
+    public void givenListWithElements_whenToArray_thenArrayContainsThose() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        list.add(".com");
+        Object[] array = list.toArray();
+
+        assertArrayEquals(new Object[] { "baeldung", ".com" }, array);
+    }
+
+    @Test
+    public void givenListWithAnElement_whenToArray_thenInputArrayIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        String[] input = new String[1];
+        String[] output = list.toArray(input);
+
+        assertArrayEquals(new String[] { "baeldung" }, input);
+    }
+
+    @Test
+    public void whenToArrayIsCalledWithEmptyInputArray_thenNewArrayIsReturned() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        String[] input = {};
+        String[] output = list.toArray(input);
+
+        assertArrayEquals(new String[] { "baeldung" }, output);
+    }
+
+    @Test
+    public void whenToArrayIsCalledWithLargerInput_thenOutputHasTrailingNull() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        String[] input = new String[2];
+        String[] output = list.toArray(input);
+
+        assertArrayEquals(new String[] { "baeldung", null }, output);
+    }
+
+    @Test
+    public void givenListWithOneElement_whenIterator_thenThisElementIsNext() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        Iterator<Object> iterator = list.iterator();
+
+        assertTrue(iterator.hasNext());
+        assertEquals("baeldung", iterator.next());
+    }
+
+    @Test
+    public void whenIteratorHasNextIsCalledTwice_thenTheSecondReturnsFalse() {
+        List<Object> list = new CustomList<>();
+        list.add("baeldung");
+        Iterator<Object> iterator = list.iterator();
+
+        iterator.next();
+        assertFalse(iterator.hasNext());
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverloadingUnitTest.java b/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverloadingUnitTest.java
new file mode 100644
index 0000000000..081a30c34a
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverloadingUnitTest.java
@@ -0,0 +1,41 @@
+package com.baeldung.methodoverloadingoverriding.test;
+
+import com.baeldung.methodoverloadingoverriding.util.Multiplier;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import static org.assertj.core.api.Assertions.*;
+
+public class MethodOverloadingUnitTest {
+    
+    private static Multiplier multiplier;
+    
+    @BeforeClass
+    public static void setUpMultiplierInstance() {
+        multiplier = new Multiplier();
+    }
+ 
+    @Test
+    public void givenMultiplierInstance_whenCalledMultiplyWithTwoIntegers_thenOneAssertion() {
+        assertThat(multiplier.multiply(10, 10)).isEqualTo(100);
+    }
+    
+    @Test
+    public void givenMultiplierInstance_whenCalledMultiplyWithTreeIntegers_thenOneAssertion() {
+        assertThat(multiplier.multiply(10, 10, 10)).isEqualTo(1000);
+    }
+    
+    @Test
+    public void givenMultiplierInstance_whenCalledMultiplyWithIntDouble_thenOneAssertion() {
+        assertThat(multiplier.multiply(10, 10.5)).isEqualTo(105.0);
+    }
+    
+    @Test
+    public void givenMultiplierInstance_whenCalledMultiplyWithDoubleDouble_thenOneAssertion() {
+        assertThat(multiplier.multiply(10.5, 10.5)).isEqualTo(110.25);
+    }
+    
+    @Test
+    public void givenMultiplierInstance_whenCalledMultiplyWithIntIntAndMatching_thenNoTypePromotion() {
+        assertThat(multiplier.multiply(10, 10)).isEqualTo(100);
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverridingUnitTest.java b/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverridingUnitTest.java
new file mode 100644
index 0000000000..554ac121bc
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverridingUnitTest.java
@@ -0,0 +1,68 @@
+package com.baeldung.methodoverloadingoverriding.test;
+
+import com.baeldung.methodoverloadingoverriding.model.Car;
+import com.baeldung.methodoverloadingoverriding.model.Vehicle;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import static org.assertj.core.api.Assertions.*;
+
+public class MethodOverridingUnitTest {
+    
+    private static Vehicle vehicle;
+    private static Car car;
+    
+    @BeforeClass
+    public static void setUpVehicleInstance() {
+        vehicle = new Vehicle();
+    }
+    
+    @BeforeClass
+    public static void setUpCarInstance() {
+        car = new Car();
+    }
+    
+    @Test
+    public void givenVehicleInstance_whenCalledAccelerate_thenOneAssertion() {
+        assertThat(vehicle.accelerate(100)).isEqualTo("The vehicle accelerates at : 100 MPH.");
+    }
+    
+    @Test
+    public void givenVehicleInstance_whenCalledRun_thenOneAssertion() {
+        assertThat(vehicle.run()).isEqualTo("The vehicle is running.");
+    }
+    
+    @Test
+    public void givenVehicleInstance_whenCalledStop_thenOneAssertion() {
+        assertThat(vehicle.stop()).isEqualTo("The vehicle has stopped.");
+    }
+    
+    @Test
+    public void givenCarInstance_whenCalledAccelerate_thenOneAssertion() {
+        assertThat(car.accelerate(80)).isEqualTo("The car accelerates at : 80 MPH.");
+    }
+    
+    @Test
+    public void givenCarInstance_whenCalledRun_thenOneAssertion() {
+        assertThat(car.run()).isEqualTo("The vehicle is running.");
+    }
+    
+    @Test
+    public void givenCarInstance_whenCalledStop_thenOneAssertion() {
+        assertThat(car.stop()).isEqualTo("The vehicle has stopped.");
+    }
+    
+    @Test
+    public void givenVehicleCarInstances_whenCalledAccelerateWithSameArgument_thenNotEqual() {
+        assertThat(vehicle.accelerate(100)).isNotEqualTo(car.accelerate(100));
+    }
+    
+    @Test
+    public void givenVehicleCarInstances_whenCalledRun_thenEqual() {
+        assertThat(vehicle.run()).isEqualTo(car.run());
+    }
+    
+    @Test
+    public void givenVehicleCarInstances_whenCalledStop_thenEqual() {
+        assertThat(vehicle.stop()).isEqualTo(car.stop());
+    }
+}
diff --git a/core-java/src/test/java/com/baeldung/recursion/RecursionExampleTest.java b/core-java/src/test/java/com/baeldung/recursion/RecursionExampleTest.java
new file mode 100644
index 0000000000..c65be24240
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/recursion/RecursionExampleTest.java
@@ -0,0 +1,61 @@
+package com.baeldung.recursion;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class RecursionExampleTest {
+    
+    RecursionExample recursion = new RecursionExample();
+
+    @Test
+    public void testPowerOf10() {
+        int p0 = recursion.powerOf10(0);
+        int p1 = recursion.powerOf10(1);
+        int p4 = recursion.powerOf10(4);
+        
+        Assert.assertEquals(1, p0);
+        Assert.assertEquals(10, p1);
+        Assert.assertEquals(10000, p4);
+    }
+    
+    @Test
+    public void testFibonacci() {
+        int n0 = recursion.fibonacci(0);
+        int n1 = recursion.fibonacci(1);
+        int n7 = recursion.fibonacci(7);
+        
+        Assert.assertEquals(0, n0);
+        Assert.assertEquals(1, n1);
+        Assert.assertEquals(13, n7);
+    }
+    
+    @Test
+    public void testToBinary() {
+        String b0 = recursion.toBinary(0);
+        String b1 = recursion.toBinary(1);
+        String b10 = recursion.toBinary(10);
+        
+        Assert.assertEquals("0", b0);
+        Assert.assertEquals("1", b1);
+        Assert.assertEquals("1010", b10);
+    }
+    
+    @Test
+    public void testCalculateTreeHeight() {
+        BinaryNode root = new BinaryNode(1);
+        root.setLeft(new BinaryNode(1));
+        root.setRight(new BinaryNode(1));
+        
+        root.getLeft().setLeft(new BinaryNode(1));
+        root.getLeft().getLeft().setRight(new BinaryNode(1));
+        root.getLeft().getLeft().getRight().setLeft(new BinaryNode(1));
+        
+        root.getRight().setLeft(new BinaryNode(1));
+        root.getRight().getLeft().setRight(new BinaryNode(1));
+        
+        int height = recursion.calculateTreeHeight(root);
+        
+        Assert.assertEquals(4, height);
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/resourcebundle/ExampleResourceUnitTest.java b/core-java/src/test/java/com/baeldung/resourcebundle/ExampleResourceUnitTest.java
new file mode 100644
index 0000000000..1ce4f1bb8f
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/resourcebundle/ExampleResourceUnitTest.java
@@ -0,0 +1,39 @@
+package com.baeldung.resourcebundle;
+
+import org.junit.Test;
+
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.Locale;
+import java.util.ResourceBundle;
+
+import static org.junit.Assert.*;
+
+public class ExampleResourceUnitTest {
+
+    @Test
+    public void whenGetBundleExampleResourceForLocalePlPl_thenItShouldInheritPropertiesGreetingAndLanguage() {
+        Locale plLocale = new Locale("pl", "PL");
+
+        ResourceBundle exampleBundle = ResourceBundle.getBundle("com.baeldung.resourcebundle.ExampleResource", plLocale);
+
+        assertTrue(exampleBundle.keySet()
+            .containsAll(Arrays.asList("toUsdRate", "cities", "greeting", "currency", "language")));
+        assertEquals(exampleBundle.getString("greeting"), "cześć");
+        assertEquals(exampleBundle.getObject("toUsdRate"), new BigDecimal("3.401"));
+        assertArrayEquals(exampleBundle.getStringArray("cities"), new String[] { "Warsaw", "Cracow" });
+    }
+
+    @Test
+    public void whenGetBundleExampleResourceForLocaleUs_thenItShouldContainOnlyGreeting() {
+        Locale usLocale = Locale.US;
+
+        ResourceBundle exampleBundle = ResourceBundle.getBundle("com.baeldung.resourcebundle.ExampleResource", usLocale);
+
+        assertFalse(exampleBundle.keySet()
+            .containsAll(Arrays.asList("toUsdRate", "cities", "currency", "language")));
+        assertTrue(exampleBundle.keySet()
+            .containsAll(Arrays.asList("greeting")));
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/resourcebundle/PropertyResourceUnitTest.java b/core-java/src/test/java/com/baeldung/resourcebundle/PropertyResourceUnitTest.java
new file mode 100644
index 0000000000..4da71567e1
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/resourcebundle/PropertyResourceUnitTest.java
@@ -0,0 +1,62 @@
+package com.baeldung.resourcebundle;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.Locale;
+import java.util.ResourceBundle;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class PropertyResourceUnitTest {
+
+    @Test
+    public void givenLocaleUsAsDefualt_whenGetBundleForLocalePlPl_thenItShouldContain3ButtonsAnd1Label() {
+        Locale.setDefault(Locale.US);
+
+        ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("pl", "PL"));
+
+        assertTrue(bundle.keySet()
+            .containsAll(Arrays.asList("backButton", "helloLabel", "cancelButton", "continueButton", "helloLabelNoEncoding")));
+    }
+
+    @Test
+    public void givenLocaleUsAsDefualt_whenGetBundleForLocaleFrFr_thenItShouldContainKeys1To3AndKey4() {
+        Locale.setDefault(Locale.US);
+
+        ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"));
+
+        assertTrue(bundle.keySet()
+            .containsAll(Arrays.asList("deleteButton", "helloLabel", "cancelButton", "continueButton")));
+    }
+
+    @Test
+    public void givenLocaleChinaAsDefualt_whenGetBundleForLocaleFrFr_thenItShouldOnlyContainKeys1To3() {
+        Locale.setDefault(Locale.CHINA);
+
+        ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"));
+
+        assertTrue(bundle.keySet()
+            .containsAll(Arrays.asList("continueButton", "helloLabel", "cancelButton")));
+    }
+
+    @Test
+    public void givenLocaleChinaAsDefualt_whenGetBundleForLocaleFrFrAndExampleControl_thenItShouldOnlyContainKey5() {
+        Locale.setDefault(Locale.CHINA);
+
+        ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"), new ExampleControl());
+
+        assertTrue(bundle.keySet()
+            .containsAll(Arrays.asList("backButton", "helloLabel")));
+    }
+
+    @Test
+    public void givenValuesDifferentlyEncoded_whenGetBundleForLocalePlPl_thenItShouldContain3ButtonsAnd1Label() {
+        ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("pl", "PL"));
+
+        assertEquals(bundle.getString("helloLabel"), "cześć");
+        assertEquals(bundle.getString("helloLabelNoEncoding"), "czeÅ\u009BÄ\u0087");
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/string/PalindromeTest.java b/core-java/src/test/java/com/baeldung/string/PalindromeTest.java
index d1a05b6617..bc6fee2cd9 100644
--- a/core-java/src/test/java/com/baeldung/string/PalindromeTest.java
+++ b/core-java/src/test/java/com/baeldung/string/PalindromeTest.java
@@ -25,84 +25,73 @@ public class PalindromeTest {
     
     @Test
     public void whenWord_shouldBePalindrome() {
-        for(String word:words)
+        for (String word : words)
             assertTrue(palindrome.isPalindrome(word));
     }
 
     @Test
     public void whenSentence_shouldBePalindrome() {
-        for(String sentence:sentences)
+        for (String sentence : sentences)
             assertTrue(palindrome.isPalindrome(sentence));
     }
-    
+
     @Test
     public void whenReverseWord_shouldBePalindrome() {
-        for(String word:words)
+        for (String word : words)
             assertTrue(palindrome.isPalindromeReverseTheString(word));
     }
-    
+
     @Test
     public void whenReverseSentence_shouldBePalindrome() {
-        for(String sentence:sentences)
+        for (String sentence : sentences)
             assertTrue(palindrome.isPalindromeReverseTheString(sentence));
     }
-    
+
     @Test
     public void whenStringBuilderWord_shouldBePalindrome() {
-        for(String word:words)
+        for (String word : words)
             assertTrue(palindrome.isPalindromeUsingStringBuilder(word));
     }
-    
+
     @Test
     public void whenStringBuilderSentence_shouldBePalindrome() {
-        for(String sentence:sentences)
+        for (String sentence : sentences)
             assertTrue(palindrome.isPalindromeUsingStringBuilder(sentence));
     }
-    
+
     @Test
     public void whenStringBufferWord_shouldBePalindrome() {
-        for(String word:words)
+        for (String word : words)
             assertTrue(palindrome.isPalindromeUsingStringBuffer(word));
     }
-    
+
     @Test
     public void whenStringBufferSentence_shouldBePalindrome() {
-        for(String sentence:sentences)
-            
+        for (String sentence : sentences)
             assertTrue(palindrome.isPalindromeUsingStringBuffer(sentence));
     }
-    
+
     @Test
     public void whenPalindromeRecursive_wordShouldBePalindrome() {
-        for(String word:words) {
-            word = word.replaceAll("\\s+", "").toLowerCase();
-            int backward = word.length()-1;
-            
-            assertTrue(palindrome.isPalindromeRecursive(word,0,backward));
-        }
+        for (String word : words)
+            assertTrue(palindrome.isPalindromeRecursive(word));
     }
-    
+
     @Test
     public void whenPalindromeRecursive_sentenceShouldBePalindrome() {
-        for(String sentence:sentences) {
-            sentence = sentence.replaceAll("\\s+", "").toLowerCase();
-            int backward = sentence.length()-1;
-            
-            assertTrue(palindrome.isPalindromeRecursive(sentence,0,backward));
-        }
+        for (String sentence : sentences)
+            assertTrue(palindrome.isPalindromeRecursive(sentence));
     }
-    
+
     @Test
     public void whenPalindromeStreams_wordShouldBePalindrome() {
-        for(String word:words) {
+        for (String word : words)
             assertTrue(palindrome.isPalindromeUsingIntStream(word));
-        }
     }
-    
+
     @Test
     public void whenPalindromeStreams_sentenceShouldBePalindrome() {
-        for(String sentence:sentences) {
+        for (String sentence : sentences)
             assertTrue(palindrome.isPalindromeUsingIntStream(sentence));
-        }
     }
 }
diff --git a/core-java/src/test/java/com/baeldung/string/StringComparisonTest.java b/core-java/src/test/java/com/baeldung/string/StringComparisonTest.java
new file mode 100644
index 0000000000..5869676004
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/string/StringComparisonTest.java
@@ -0,0 +1,154 @@
+package com.baeldung.string;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.Test;
+
+import java.util.Objects;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class StringComparisonTest {
+
+    @Test
+    public void whenUsingComparisonOperator_ThenComparingStrings(){
+
+        String string1 = "using comparison operator";
+        String string2 = "using comparison operator";
+        String string3 = new String("using comparison operator");
+
+        assertThat(string1 == string2).isTrue();
+        assertThat(string1 == string3).isFalse();
+    }
+
+    @Test
+    public void whenUsingEqualsMethod_ThenComparingStrings(){
+
+        String string1 = "using equals method";
+        String string2 = "using equals method";
+
+        String string3 = "using EQUALS method";
+        String string4 = new String("using equals method");
+
+        assertThat(string1.equals(string2)).isTrue();
+        assertThat(string1.equals(string4)).isTrue();
+
+        assertThat(string1.equals(null)).isFalse();
+        assertThat(string1.equals(string3)).isFalse();
+    }
+
+    @Test
+    public void whenUsingEqualsIgnoreCase_ThenComparingStrings(){
+
+        String string1 = "using equals ignore case";
+        String string2 = "USING EQUALS IGNORE CASE";
+
+        assertThat(string1.equalsIgnoreCase(string2)).isTrue();
+    }
+
+    @Test
+    public void whenUsingCompareTo_ThenComparingStrings(){
+
+        String author = "author";
+        String book = "book";
+        String duplicateBook = "book";
+
+        assertThat(author.compareTo(book)).isEqualTo(-1);
+        assertThat(book.compareTo(author)).isEqualTo(1);
+        assertThat(duplicateBook.compareTo(book)).isEqualTo(0);
+    }
+
+    @Test
+    public void whenUsingCompareToIgnoreCase_ThenComparingStrings(){
+
+        String author = "Author";
+        String book = "book";
+        String duplicateBook = "BOOK";
+
+        assertThat(author.compareToIgnoreCase(book)).isEqualTo(-1);
+        assertThat(book.compareToIgnoreCase(author)).isEqualTo(1);
+        assertThat(duplicateBook.compareToIgnoreCase(book)).isEqualTo(0);
+    }
+
+    @Test
+    public void whenUsingObjectsEqualsMethod_ThenComparingStrings(){
+
+        String string1 = "using objects equals";
+        String string2 = "using objects equals";
+        String string3 = new String("using objects equals");
+
+        assertThat(Objects.equals(string1, string2)).isTrue();
+        assertThat(Objects.equals(string1, string3)).isTrue();
+
+        assertThat(Objects.equals(null, null)).isTrue();
+        assertThat(Objects.equals(null, string1)).isFalse();
+    }
+
+    @Test
+    public void whenUsingEqualsOfApacheCommons_ThenComparingStrings(){
+
+        assertThat(StringUtils.equals(null, null)).isTrue();
+        assertThat(StringUtils.equals(null, "equals method")).isFalse();
+        assertThat(StringUtils.equals("equals method", "equals method")).isTrue();
+        assertThat(StringUtils.equals("equals method", "EQUALS METHOD")).isFalse();
+    }
+
+    @Test
+    public void whenUsingEqualsIgnoreCaseOfApacheCommons_ThenComparingStrings(){
+
+        assertThat(StringUtils.equalsIgnoreCase(null, null)).isTrue();
+        assertThat(StringUtils.equalsIgnoreCase(null, "equals method")).isFalse();
+        assertThat(StringUtils.equalsIgnoreCase("equals method", "equals method")).isTrue();
+        assertThat(StringUtils.equalsIgnoreCase("equals method", "EQUALS METHOD")).isTrue();
+    }
+
+    @Test
+    public void whenUsingEqualsAnyOf_ThenComparingStrings(){
+
+        assertThat(StringUtils.equalsAny(null, null, null)).isTrue();
+        assertThat(StringUtils.equalsAny("equals any", "equals any", "any")).isTrue();
+        assertThat(StringUtils.equalsAny("equals any", null, "equals any")).isTrue();
+        assertThat(StringUtils.equalsAny(null, "equals", "any")).isFalse();
+        assertThat(StringUtils.equalsAny("equals any", "EQUALS ANY", "ANY")).isFalse();
+    }
+
+    @Test
+    public void whenUsingEqualsAnyIgnoreCase_ThenComparingStrings(){
+
+        assertThat(StringUtils.equalsAnyIgnoreCase(null, null, null)).isTrue();
+        assertThat(StringUtils.equalsAnyIgnoreCase("equals any", "equals any", "any")).isTrue();
+        assertThat(StringUtils.equalsAnyIgnoreCase("equals any", null, "equals any")).isTrue();
+        assertThat(StringUtils.equalsAnyIgnoreCase(null, "equals", "any")).isFalse();
+        assertThat(StringUtils.equalsAnyIgnoreCase(
+                "equals any ignore case", "EQUALS ANY IGNORE CASE", "any")).isTrue();
+    }
+
+    @Test
+    public void whenUsingCompare_thenComparingStringsWithNulls(){
+
+        assertThat(StringUtils.compare(null, null)).isEqualTo(0);
+        assertThat(StringUtils.compare(null, "abc")).isEqualTo(-1);
+
+        assertThat(StringUtils.compare("abc", "bbc")).isEqualTo(-1);
+        assertThat(StringUtils.compare("bbc", "abc")).isEqualTo(1);
+        assertThat(StringUtils.compare("abc", "abc")).isEqualTo(0);
+    }
+
+    @Test
+    public void whenUsingCompareIgnoreCase_ThenComparingStringsWithNulls(){
+
+        assertThat(StringUtils.compareIgnoreCase(null, null)).isEqualTo(0);
+        assertThat(StringUtils.compareIgnoreCase(null, "abc")).isEqualTo(-1);
+
+        assertThat(StringUtils.compareIgnoreCase("Abc", "bbc")).isEqualTo(-1);
+        assertThat(StringUtils.compareIgnoreCase("bbc", "ABC")).isEqualTo(1);
+        assertThat(StringUtils.compareIgnoreCase("abc", "ABC")).isEqualTo(0);
+    }
+
+    @Test
+    public void whenUsingCompareWithNullIsLessOption_ThenComparingStrings(){
+
+        assertThat(StringUtils.compare(null, "abc", true)).isEqualTo(-1);
+        assertThat(StringUtils.compare(null, "abc", false)).isEqualTo(1);
+    }
+
+}
diff --git a/core-java/src/test/java/com/baeldung/system/WhenDetectingOSTest.java b/core-java/src/test/java/com/baeldung/system/WhenDetectingOSTest.java
new file mode 100644
index 0000000000..77901f6524
--- /dev/null
+++ b/core-java/src/test/java/com/baeldung/system/WhenDetectingOSTest.java
@@ -0,0 +1,25 @@
+package com.baeldung.system;
+
+import org.junit.Assert;
+import org.junit.Ignore;
+import org.junit.Test;
+
+@Ignore
+public class WhenDetectingOSTest {
+
+    private DetectOS os = new DetectOS();
+
+    @Test
+    public void whenUsingSystemProperty_shouldReturnOS() {
+        String expected = "Windows 10";
+        String actual = os.getOperatingSystem();
+        Assert.assertEquals(expected, actual);
+    }
+
+    @Test
+    public void whenUsingSystemUtils_shouldReturnOS() {
+        String expected = "Windows 10";
+        String actual = os.getOperatingSystemSystemUtils();
+        Assert.assertEquals(expected, actual);
+    }
+}
diff --git a/core-kotlin/README.md b/core-kotlin/README.md
index 5908d480b7..1c64817815 100644
--- a/core-kotlin/README.md
+++ b/core-kotlin/README.md
@@ -17,4 +17,4 @@
 - [Sealed Classes in Kotlin](http://www.baeldung.com/kotlin-sealed-classes)
 - [JUnit 5 for Kotlin Developers](http://www.baeldung.com/junit-5-kotlin)
 - [Extension Methods in Kotlin](http://www.baeldung.com/kotlin-extension-methods)
-
+- [Infix Functions in Kotlin](http://www.baeldung.com/kotlin-infix-functions)
diff --git a/core-kotlin/pom.xml b/core-kotlin/pom.xml
index 33bdbf719f..36298ca084 100644
--- a/core-kotlin/pom.xml
+++ b/core-kotlin/pom.xml
@@ -76,7 +76,18 @@
             <artifactId>mockito-kotlin</artifactId>
             <version>${mockito-kotlin.version}</version>
             <scope>test</scope>
-        </dependency>        
+        </dependency>
+        <dependency>
+            <groupId>com.github.salomonbrys.kodein</groupId>
+            <artifactId>kodein</artifactId>
+            <version>${kodein.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
@@ -189,11 +200,13 @@
         <kotlin-reflect.version>1.1.2</kotlin-reflect.version>
         <kotlinx.version>0.15</kotlinx.version>
         <mockito-kotlin.version>1.5.0</mockito-kotlin.version>
+        <kodein.version>4.1.0</kodein.version>
 
         <junit.jupiter.version>5.0.0</junit.jupiter.version>
         <junit.platform.version>1.0.0</junit.platform.version>
         <junit.vintage.version>4.12.0</junit.vintage.version>
         <junit4.version>4.12</junit4.version>
+        <assertj.version>3.9.1</assertj.version>
     </properties>
 
 </project>
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Controller.kt b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Controller.kt
new file mode 100644
index 0000000000..721bdb04bc
--- /dev/null
+++ b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Controller.kt
@@ -0,0 +1,3 @@
+package com.baeldung.kotlin.kodein
+
+class Controller(private val service : Service)
\ No newline at end of file
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Dao.kt b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Dao.kt
new file mode 100644
index 0000000000..a0be7ef0e0
--- /dev/null
+++ b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Dao.kt
@@ -0,0 +1,3 @@
+package com.baeldung.kotlin.kodein
+
+interface Dao
\ No newline at end of file
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/JdbcDao.kt b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/JdbcDao.kt
new file mode 100644
index 0000000000..0a09b95dbf
--- /dev/null
+++ b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/JdbcDao.kt
@@ -0,0 +1,3 @@
+package com.baeldung.kotlin.kodein
+
+class JdbcDao : Dao
\ No newline at end of file
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/MongoDao.kt b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/MongoDao.kt
new file mode 100644
index 0000000000..06436fcd21
--- /dev/null
+++ b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/MongoDao.kt
@@ -0,0 +1,3 @@
+package com.baeldung.kotlin.kodein
+
+class MongoDao : Dao
\ No newline at end of file
diff --git a/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Service.kt b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Service.kt
new file mode 100644
index 0000000000..bb24a5cc21
--- /dev/null
+++ b/core-kotlin/src/main/kotlin/com/baeldung/kotlin/kodein/Service.kt
@@ -0,0 +1,3 @@
+package com.baeldung.kotlin.kodein
+
+class Service(private val dao: Dao, private val tag: String)
\ No newline at end of file
diff --git a/core-kotlin/src/test/kotlin/com/baeldung/kotlin/kodein/KodeinUnitTest.kt b/core-kotlin/src/test/kotlin/com/baeldung/kotlin/kodein/KodeinUnitTest.kt
new file mode 100644
index 0000000000..7776eebd52
--- /dev/null
+++ b/core-kotlin/src/test/kotlin/com/baeldung/kotlin/kodein/KodeinUnitTest.kt
@@ -0,0 +1,191 @@
+package com.baeldung.kotlin.kodein
+
+import com.github.salomonbrys.kodein.*
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.Test
+
+class KodeinUnitTest {
+
+    class InMemoryDao : Dao
+
+    @Test
+    fun whenSingletonBinding_thenSingleInstanceIsCreated() {
+        var created = false
+        val kodein = Kodein {
+            bind<Dao>() with singleton {
+                created = true
+                MongoDao()
+            }
+        }
+
+        assertThat(created).isFalse()
+
+        val dao1: Dao = kodein.instance()
+
+        assertThat(created).isTrue()
+
+        val dao2: Dao = kodein.instance()
+
+        assertThat(dao1).isSameAs(dao2)
+    }
+
+    @Test
+    fun whenFactoryBinding_thenNewInstanceIsCreated() {
+        val kodein = Kodein {
+            bind<Dao>() with singleton { MongoDao() }
+            bind<Service>() with factory { tag: String -> Service(instance(), tag) }
+        }
+        val service1: Service = kodein.with("myTag").instance()
+        val service2: Service = kodein.with("myTag").instance()
+
+        assertThat(service1).isNotSameAs(service2)
+    }
+
+    @Test
+    fun whenProviderBinding_thenNewInstanceIsCreated() {
+        val kodein = Kodein {
+            bind<Dao>() with provider { MongoDao() }
+        }
+        val dao1: Dao = kodein.instance()
+        val dao2: Dao = kodein.instance()
+
+        assertThat(dao1).isNotSameAs(dao2)
+    }
+
+    @Test
+    fun whenTaggedBinding_thenMultipleInstancesOfSameTypeCanBeRegistered() {
+        val kodein = Kodein {
+            bind<Dao>("dao1") with singleton { MongoDao() }
+            bind<Dao>("dao2") with singleton { MongoDao() }
+        }
+        val dao1: Dao = kodein.instance("dao1")
+        val dao2: Dao = kodein.instance("dao2")
+
+        assertThat(dao1).isNotSameAs(dao2)
+    }
+
+    @Test
+    fun whenEagerSingletonBinding_thenCreationIsEager() {
+        var created = false
+        val kodein = Kodein {
+            bind<Dao>() with eagerSingleton {
+                created = true
+                MongoDao()
+            }
+        }
+
+        assertThat(created).isTrue()
+        val dao1: Dao = kodein.instance()
+        val dao2: Dao = kodein.instance()
+
+        assertThat(dao1).isSameAs(dao2)
+    }
+
+    @Test
+    fun whenMultitonBinding_thenInstancesAreReused() {
+        val kodein = Kodein {
+            bind<Dao>() with singleton { MongoDao() }
+            bind<Service>() with multiton { tag: String -> Service(instance(), tag) }
+        }
+        val service1: Service = kodein.with("myTag").instance()
+        val service2: Service = kodein.with("myTag").instance()
+
+        assertThat(service1).isSameAs(service2)
+    }
+
+    @Test
+    fun whenInstanceBinding_thenItIsReused() {
+        val dao = MongoDao()
+        val kodein = Kodein {
+            bind<Dao>() with instance(dao)
+        }
+        val fromContainer: Dao = kodein.instance()
+
+        assertThat(dao).isSameAs(fromContainer)
+    }
+
+    @Test
+    fun whenConstantBinding_thenItIsAvailable() {
+        val kodein = Kodein {
+            constant("magic") with 42
+        }
+        val fromContainer: Int = kodein.instance("magic")
+
+        assertThat(fromContainer).isEqualTo(42)
+    }
+
+    @Test
+    fun whenUsingModules_thenTransitiveDependenciesAreSuccessfullyResolved() {
+        val jdbcModule = Kodein.Module {
+            bind<Dao>() with singleton { JdbcDao() }
+        }
+        val kodein = Kodein {
+            import(jdbcModule)
+            bind<Controller>() with singleton { Controller(instance()) }
+            bind<Service>() with singleton { Service(instance(), "myService") }
+        }
+
+        val dao: Dao = kodein.instance()
+        assertThat(dao).isInstanceOf(JdbcDao::class.java)
+    }
+
+    @Test
+    fun whenComposition_thenBeansAreReUsed() {
+        val persistenceContainer = Kodein {
+            bind<Dao>() with singleton { MongoDao() }
+        }
+        val serviceContainer = Kodein {
+            extend(persistenceContainer)
+            bind<Service>() with singleton { Service(instance(), "myService") }
+        }
+        val fromPersistence: Dao = persistenceContainer.instance()
+        val fromService: Dao = serviceContainer.instance()
+
+        assertThat(fromPersistence).isSameAs(fromService)
+    }
+
+    @Test
+    fun whenOverriding_thenRightBeanIsUsed() {
+        val commonModule = Kodein.Module {
+            bind<Dao>() with singleton { MongoDao() }
+            bind<Service>() with singleton { Service(instance(), "myService") }
+        }
+        val testContainer = Kodein {
+            import(commonModule)
+            bind<Dao>(overrides = true) with singleton { InMemoryDao() }
+        }
+        val dao: Dao = testContainer.instance()
+
+        assertThat(dao).isInstanceOf(InMemoryDao::class.java)
+    }
+
+    @Test
+    fun whenMultiBinding_thenWorks() {
+        val kodein = Kodein {
+            bind() from setBinding<Dao>()
+            bind<Dao>().inSet() with singleton { MongoDao() }
+            bind<Dao>().inSet() with singleton { JdbcDao() }
+        }
+        val daos: Set<Dao> = kodein.instance()
+
+        assertThat(daos.map { it.javaClass as Class<*> }).containsOnly(MongoDao::class.java, JdbcDao::class.java)
+    }
+
+    @Test
+    fun whenInjector_thenWorks() {
+        class Controller2 {
+            private val injector = KodeinInjector()
+            val service: Service by injector.instance()
+            fun injectDependencies(kodein: Kodein) = injector.inject(kodein)
+        }
+
+        val kodein = Kodein {
+            bind<Dao>() with singleton { MongoDao() }
+            bind<Service>() with singleton { Service(instance(), "myService") }
+        }
+        val controller = Controller2()
+        controller.injectDependencies(kodein)
+
+        assertThat(controller.service).isNotNull
+    }
+}
\ No newline at end of file
diff --git a/ethereumj/pom.xml b/ethereumj/pom.xml
index c9f5924d7a..9676106e38 100644
--- a/ethereumj/pom.xml
+++ b/ethereumj/pom.xml
@@ -1,6 +1,5 @@
 <?xml version="1.0"?>
-<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
-         xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung.ethereumj</groupId>
     <artifactId>ethereumj</artifactId>
@@ -8,16 +7,11 @@
     <version>1.0.0</version>
     <name>ethereumj</name>
 
-    <properties>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <java.version>1.8</java.version>
-        <tomcat.version>8.5.4</tomcat.version>
-    </properties>
-
     <parent>
-        <groupId>org.springframework.boot</groupId>
-        <artifactId>spring-boot-starter-parent</artifactId>
-        <version>1.5.6.RELEASE</version>
+        <artifactId>parent-boot-5</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-boot-5</relativePath>
     </parent>
 
     <repositories>
@@ -38,14 +32,12 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-tomcat</artifactId>
-            <!--<scope>provided</scope>-->
         </dependency>
 
         <!-- Unit Testing -->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.6.RELEASE</version>
             <scope>test</scope>
         </dependency>
 
@@ -107,4 +99,11 @@
             </build>
         </profile>
     </profiles>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <java.version>1.8</java.version>
+        <tomcat.version>8.5.4</tomcat.version>
+    </properties>
+
 </project>
\ No newline at end of file
diff --git a/google-cloud/README.md b/google-cloud/README.md
new file mode 100644
index 0000000000..6022796a0e
--- /dev/null
+++ b/google-cloud/README.md
@@ -0,0 +1,16 @@
+## Google Cloud Tutorial Project
+
+### Relevant Article:
+- [Intro to Google Cloud Storage With Java](http://www.baeldung.com/intro-to-google-cloud-storage-with-java/)
+
+### Overview
+This Maven project contains the Java code for the article linked above.
+
+### Package Organization
+Java classes for the intro tutorial are in the org.baeldung.google.cloud package. Please note that Google Cloud requires
+a user account and credentials, as explained in the tutorial.
+
+
+### Running the tests
+
+```
diff --git a/google-cloud/pom.xml b/google-cloud/pom.xml
new file mode 100644
index 0000000000..0f1eff36f8
--- /dev/null
+++ b/google-cloud/pom.xml
@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>google-cloud</artifactId>
+    <version>0.1-SNAPSHOT</version>
+    <packaging>jar</packaging>
+    <name>google-cloud</name>
+    <description>Google Cloud Tutorials</description>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.google.cloud</groupId>
+            <artifactId>google-cloud-storage</artifactId>
+            <version>1.16.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <!-- Check for the most recent available version: https://projectlombok.org/changelog.html -->
+            <version>${lombok.version}</version>
+            <scope>provided</scope>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <lombok.version>1.16.18</lombok.version>
+        <java.version>1.8</java.version>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    </properties>
+
+</project>
diff --git a/google-cloud/src/main/java/com/baeldung/google/cloud/storage/GoogleCloudStorage.java b/google-cloud/src/main/java/com/baeldung/google/cloud/storage/GoogleCloudStorage.java
new file mode 100644
index 0000000000..a69171f1db
--- /dev/null
+++ b/google-cloud/src/main/java/com/baeldung/google/cloud/storage/GoogleCloudStorage.java
@@ -0,0 +1,105 @@
+package com.baeldung.google.cloud.storage;
+
+import com.google.api.gax.paging.Page;
+import com.google.auth.Credentials;
+import com.google.auth.oauth2.GoogleCredentials;
+import com.google.cloud.storage.*;
+import lombok.extern.slf4j.Slf4j;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.WritableByteChannel;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+/**
+ * Simple class for creating, reading and modifying text blobs on Google Cloud
+ */
+@Slf4j
+public class GoogleCloudStorage {
+
+    private Storage storage;
+    private Bucket bucket;
+
+    public static void main(String[] args) throws Exception {
+
+        // Use this variation to read the Google authorization JSON from the resources directory with a path
+        // and a project name.
+        GoogleCloudStorage googleCloudStorage =
+            new GoogleCloudStorage("google-cloud/src/main/resources/google_auth.json", "baeldung-cloud-tutorial");
+
+        // Bucket require globally unique names, so you'll probably need to change this
+        Bucket bucket = googleCloudStorage.getBucket("baeldung-1-bucket");
+
+        // Save a simple string
+        BlobId blobId = googleCloudStorage.saveString("my-first-blob", "Hi there!", bucket);
+
+        // Get it by blob id this time
+        String value = googleCloudStorage.getString(blobId);
+
+        log.info("Read data: {}", value);
+
+        googleCloudStorage.updateString(blobId, "Bye now!");
+
+        // Get the string by blob name
+        value = googleCloudStorage.getString("my-first-blob");
+
+        log.info("Read modified data: {}", value);
+
+
+    }
+
+
+    // Use path and project name
+    private GoogleCloudStorage(String pathToConfig, String projectId) throws IOException {
+        Credentials credentials = GoogleCredentials.fromStream(new FileInputStream(pathToConfig));
+        storage = StorageOptions.newBuilder().setCredentials(credentials).setProjectId(projectId).build().getService();
+    }
+
+    // Check for bucket existence and create if needed.
+    private Bucket getBucket(String bucketName) {
+        bucket = storage.get(bucketName);
+        if (bucket == null) {
+            System.out.println("Creating new bucket.");
+            bucket = storage.create(BucketInfo.of(bucketName));
+        }
+        return bucket;
+    }
+
+    // Save a string to a blob
+    private BlobId saveString(String blobName, String value, Bucket bucket) {
+        byte[] bytes = value.getBytes(UTF_8);
+        Blob blob = bucket.create(blobName, bytes);
+        return blob.getBlobId();
+    }
+
+
+    // get a blob by id
+    private String getString(BlobId blobId) {
+        Blob blob = storage.get(blobId);
+        return new String(blob.getContent());
+    }
+
+
+    // get a blob by name
+    private String getString(String name) {
+        Page<Blob> blobs = bucket.list();
+        for (Blob blob: blobs.getValues()) {
+            if (name.equals(blob.getName())) {
+                return new String(blob.getContent());
+            }
+        }
+        return "Blob not found";
+    }
+
+    // Update a blob
+    private void updateString(BlobId blobId, String newString) throws IOException {
+        Blob blob = storage.get(blobId);
+        if (blob != null) {
+            WritableByteChannel channel = blob.writer();
+            channel.write(ByteBuffer.wrap(newString.getBytes(UTF_8)));
+            channel.close();
+        }
+    }
+}
\ No newline at end of file
diff --git a/gradle/build.gradle b/gradle/build.gradle
index dcc592a2b4..2e5d984fba 100644
--- a/gradle/build.gradle
+++ b/gradle/build.gradle
@@ -33,3 +33,60 @@ task execSecondTest {
     }
     println 'This will be executed during the configuration phase as well.'
 }
+
+task welcome {
+    doLast {
+        println 'Welcome on the Baeldung!'
+    }
+}
+
+task welcomeWithGroup {
+    group 'Sample category'
+    doLast {
+        println 'Welcome on the Baeldung!'
+    }
+}
+
+task welcomeWithGroupAndDescription {
+    group 'Sample category'
+    description 'Tasks which shows welcome message'
+    doLast {
+        println 'Welcome on the Baeldung!'
+    }
+}
+
+class PrintToolVersionTask extends DefaultTask {
+    String tool
+
+    @TaskAction
+    void printToolVersion() {
+        switch (tool) {
+            case 'java':
+                println System.getProperty("java.version")
+                break
+            case 'groovy':
+                println GroovySystem.version
+                break
+            default:
+                throw new IllegalArgumentException("Unknown tool")
+        }
+    }
+}
+
+task printJavaVersion(type : PrintToolVersionTask) {
+    tool 'java'
+}
+
+task printGroovyVersion(type : PrintToolVersionTask) {
+    tool 'groovy'
+}
+
+import com.baeldung.PrintToolVersionBuildSrcTask
+
+task printJavaVersionBuildSrc(type : PrintToolVersionBuildSrcTask) {
+    tool 'java'
+}
+
+task printGroovyVersionBuildSrc(type : PrintToolVersionBuildSrcTask) {
+    tool 'groovy'
+}
\ No newline at end of file
diff --git a/gradle/buildSrc/src/main/groovy/com/baeldung/PrintToolVersionBuildSrcTask.groovy b/gradle/buildSrc/src/main/groovy/com/baeldung/PrintToolVersionBuildSrcTask.groovy
new file mode 100644
index 0000000000..0fbd71db56
--- /dev/null
+++ b/gradle/buildSrc/src/main/groovy/com/baeldung/PrintToolVersionBuildSrcTask.groovy
@@ -0,0 +1,22 @@
+package com.baeldung
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.tasks.TaskAction
+
+class PrintToolVersionBuildSrcTask extends DefaultTask {
+    String tool
+
+    @TaskAction
+    void printToolVersion() {
+        switch (tool) {
+            case 'java':
+                println System.getProperty("java.version")
+                break
+            case 'groovy':
+                println GroovySystem.version
+                break
+            default:
+                throw new IllegalArgumentException("Unknown tool")
+        }
+    }
+}
\ No newline at end of file
diff --git a/guava/README.md b/guava/README.md
index 7ab70cb01f..924187867e 100644
--- a/guava/README.md
+++ b/guava/README.md
@@ -19,6 +19,7 @@
 - [Guide to Guava’s Ordering](http://www.baeldung.com/guava-ordering)
 - [Guide to Guava’s PreConditions](http://www.baeldung.com/guava-preconditions)
 - [Introduction to Guava CacheLoader](http://www.baeldung.com/guava-cacheloader)
+- [Introduction to Guava Memoizer](http://www.baeldung.com/guava-memoizer)
 - [Guide to Guava’s EventBus](http://www.baeldung.com/guava-eventbus)
 - [Guide to Guava Multimap](http://www.baeldung.com/guava-multimap)
 - [Guide to Guava RangeSet](http://www.baeldung.com/guava-rangeset)
diff --git a/guava/pom.xml b/guava/pom.xml
index 4afb4da301..aa162b7d1b 100644
--- a/guava/pom.xml
+++ b/guava/pom.xml
@@ -43,6 +43,14 @@
             <version>${assertj.version}</version>
             <scope>test</scope>
         </dependency>
+        
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>java-hamcrest</artifactId>
+            <version>2.0.0.0</version>
+            <scope>test</scope>
+        </dependency>
+        
     </dependencies>
 
     <build>
diff --git a/guava/src/test/java/org/baeldung/hamcrest/HamcrestFileUnitTest.java b/guava/src/test/java/org/baeldung/hamcrest/HamcrestFileUnitTest.java
new file mode 100644
index 0000000000..652e315651
--- /dev/null
+++ b/guava/src/test/java/org/baeldung/hamcrest/HamcrestFileUnitTest.java
@@ -0,0 +1,64 @@
+package org.baeldung.hamcrest;
+
+import static org.hamcrest.core.StringContains.containsString;
+import static org.hamcrest.io.FileMatchers.aFileNamed;
+import static org.hamcrest.io.FileMatchers.aFileWithAbsolutePath;
+import static org.hamcrest.io.FileMatchers.aFileWithCanonicalPath;
+import static org.hamcrest.io.FileMatchers.aFileWithSize;
+import static org.hamcrest.io.FileMatchers.aReadableFile;
+import static org.hamcrest.io.FileMatchers.aWritableFile;
+import static org.hamcrest.io.FileMatchers.anExistingDirectory;
+import static org.hamcrest.io.FileMatchers.anExistingFile;
+import static org.hamcrest.io.FileMatchers.anExistingFileOrDirectory;
+import static org.hamcrest.number.OrderingComparison.greaterThan;
+import static org.hamcrest.text.IsEqualIgnoringCase.equalToIgnoringCase;
+import static org.junit.Assert.assertThat;
+
+import java.io.File;
+
+import org.junit.Test;
+
+public class HamcrestFileUnitTest {
+
+    @Test
+    public final void whenVerifyingFileName_thenCorrect() {
+        File file = new File("src/test/resources/test1.in");
+
+        assertThat(file, aFileNamed(equalToIgnoringCase("test1.in")));
+    }
+
+    @Test
+    public final void whenVerifyingFileOrDirExist_thenCorrect() {
+        File file = new File("src/test/resources/test1.in");
+        File dir = new File("src/test/resources");
+        
+        assertThat(file, anExistingFile());
+        assertThat(dir, anExistingDirectory());
+        assertThat(file, anExistingFileOrDirectory());
+        assertThat(dir, anExistingFileOrDirectory());
+    }
+
+    @Test
+    public final void whenVerifyingFileIsReadableAndWritable_thenCorrect() {
+        File file = new File("src/test/resources/test1.in");
+
+        assertThat(file, aReadableFile());
+        assertThat(file, aWritableFile());        
+    }
+
+    @Test
+    public final void whenVerifyingFileSize_thenCorrect() {
+        File file = new File("src/test/resources/test1.in");
+
+        assertThat(file, aFileWithSize(11));
+        assertThat(file, aFileWithSize(greaterThan(1L)));;
+    }
+
+    @Test
+    public final void whenVerifyingFilePath_thenCorrect() {
+        File file = new File("src/test/resources/test1.in");
+        
+        assertThat(file, aFileWithCanonicalPath(containsString("src/test/resources")));
+        assertThat(file, aFileWithAbsolutePath(containsString("src/test/resources")));
+    }
+}
diff --git a/guava/src/test/java/org/baeldung/hamcrest/HamcrestTextUnitTest.java b/guava/src/test/java/org/baeldung/hamcrest/HamcrestTextUnitTest.java
new file mode 100644
index 0000000000..e336b1bba3
--- /dev/null
+++ b/guava/src/test/java/org/baeldung/hamcrest/HamcrestTextUnitTest.java
@@ -0,0 +1,97 @@
+package org.baeldung.hamcrest;
+
+import static org.hamcrest.core.StringContains.containsString;
+import static org.hamcrest.core.StringContains.containsStringIgnoringCase;
+import static org.hamcrest.core.StringEndsWith.endsWith;
+import static org.hamcrest.core.StringEndsWith.endsWithIgnoringCase;
+import static org.hamcrest.core.StringStartsWith.startsWith;
+import static org.hamcrest.core.StringStartsWith.startsWithIgnoringCase;
+import static org.hamcrest.text.IsBlankString.blankOrNullString;
+import static org.hamcrest.text.IsBlankString.blankString;
+import static org.hamcrest.text.IsEmptyString.emptyOrNullString;
+import static org.hamcrest.text.IsEmptyString.emptyString;
+import static org.hamcrest.text.IsEqualIgnoringCase.equalToIgnoringCase;
+import static org.hamcrest.text.IsEqualIgnoringWhiteSpace.equalToIgnoringWhiteSpace;
+import static org.hamcrest.text.MatchesPattern.matchesPattern;
+import static org.hamcrest.text.StringContainsInOrder.stringContainsInOrder;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+
+public class HamcrestTextUnitTest {
+    
+    @Test
+    public final void whenTwoStringsAreEqual_thenCorrect() {
+        String first = "hello";
+        String second = "Hello";
+        
+        assertThat(first, equalToIgnoringCase(second));
+    }
+
+    @Test
+    public final void whenTwoStringsAreEqualWithWhiteSpace_thenCorrect() {
+        String first = "hello";
+        String second = "   Hello   ";
+        
+        assertThat(first, equalToIgnoringWhiteSpace(second));
+    }
+
+    @Test
+    public final void whenStringIsBlank_thenCorrect() {
+        String first = "  ";
+        String second = null;
+
+        assertThat(first, blankString());
+        assertThat(first, blankOrNullString());
+        assertThat(second, blankOrNullString());
+    }
+
+    @Test
+    public final void whenStringIsEmpty_thenCorrect() {
+        String first = "";
+        String second = null;
+
+        assertThat(first, emptyString());
+        assertThat(first, emptyOrNullString());
+        assertThat(second, emptyOrNullString());
+    }
+
+    @Test
+    public final void whenStringMatchPattern_thenCorrect() {
+        String first = "hello";
+
+        assertThat(first, matchesPattern("[a-z]+"));
+    }
+
+    @Test
+    public final void whenVerifyStringContains_thenCorrect() {
+        String first = "hello";
+    
+        assertThat(first, containsString("lo"));
+        assertThat(first, containsStringIgnoringCase("EL"));
+    }
+    
+    @Test
+    public final void whenVerifyStringContainsInOrder_thenCorrect() {
+        String first = "hello";
+    
+        assertThat(first, stringContainsInOrder("e","l","o"));
+    }
+    
+    @Test
+    public final void whenVerifyStringStartsWith_thenCorrect() {
+        String first = "hello";
+    
+        assertThat(first, startsWith("he"));
+        assertThat(first, startsWithIgnoringCase("HEL"));
+    }
+    
+    @Test
+    public final void whenVerifyStringEndsWith_thenCorrect() {
+        String first = "hello";
+    
+        assertThat(first, endsWith("lo"));
+        assertThat(first, endsWithIgnoringCase("LO"));
+    }
+    
+}
diff --git a/guest/core-java/pom.xml b/guest/core-java/pom.xml
index 222716386b..eda3846c1f 100644
--- a/guest/core-java/pom.xml
+++ b/guest/core-java/pom.xml
@@ -16,6 +16,24 @@
 			<artifactId>log4j-core</artifactId>
 			<version>${log4j2.version}</version>
 		</dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-core</artifactId>
+            <version>${org.hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-library</artifactId>
+            <version>${org.hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-all</artifactId>
+            <version>${org.hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
 	</dependencies>
 
 	<build>
@@ -32,5 +50,6 @@
 	</build>
 	<properties>
 		<log4j2.version>2.8.2</log4j2.version>
+		<org.hamcrest.version>1.3</org.hamcrest.version>
 	</properties>
 </project>
\ No newline at end of file
diff --git a/guest/core-java/src/main/java/com/stackify/stream/Employee.java b/guest/core-java/src/main/java/com/stackify/stream/Employee.java
new file mode 100644
index 0000000000..005990c863
--- /dev/null
+++ b/guest/core-java/src/main/java/com/stackify/stream/Employee.java
@@ -0,0 +1,46 @@
+package com.stackify.stream;
+
+public class Employee {
+    private Integer id;
+    private String name;
+    private Double salary;
+    
+    public Employee(Integer id, String name, Double salary) {
+        this.id = id;
+        this.name = name;        
+        this.salary = salary;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+    
+    public Double getSalary() {
+        return salary;
+    }
+
+    public void setSalary(Double salary) {
+        this.salary = salary;
+    }
+    
+    public void salaryIncrement(Double percentage) {
+        Double newSalary = salary + percentage * salary / 100;
+        setSalary(newSalary);
+    }
+
+    public String toString() {
+        return "Id: " + id + " Name:" + name + " Price:" + salary;
+    }
+}
diff --git a/guest/core-java/src/main/java/com/stackify/stream/EmployeeRepository.java b/guest/core-java/src/main/java/com/stackify/stream/EmployeeRepository.java
new file mode 100644
index 0000000000..223fee5e26
--- /dev/null
+++ b/guest/core-java/src/main/java/com/stackify/stream/EmployeeRepository.java
@@ -0,0 +1,21 @@
+package com.stackify.stream;
+
+import java.util.List;
+
+public class EmployeeRepository {
+    private List<Employee> empList;
+    
+    public EmployeeRepository(List<Employee> empList) {
+        this.empList = empList;
+    
+    }
+    public Employee findById(Integer id) {
+        for (Employee emp : empList) {
+            if (emp.getId() == id) {
+                return emp;
+            }
+        }
+        
+        return null;
+    }
+}
diff --git a/guest/core-java/src/test/java/com/stackify/stream/EmployeeTest.java b/guest/core-java/src/test/java/com/stackify/stream/EmployeeTest.java
new file mode 100644
index 0000000000..cf988d035a
--- /dev/null
+++ b/guest/core-java/src/test/java/com/stackify/stream/EmployeeTest.java
@@ -0,0 +1,455 @@
+package com.stackify.stream;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.beans.HasPropertyWithValue.hasProperty;
+import static org.junit.Assert.assertEquals;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.DoubleSummaryStatistics;
+import java.util.List;
+import java.util.Map;
+import java.util.NoSuchElementException;
+import java.util.Optional;
+import java.util.Set;
+import java.util.Vector;
+import java.util.function.BinaryOperator;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.junit.After;
+import org.junit.Test;
+
+public class EmployeeTest {
+    private String fileName = "src/test/resources/test.txt";
+    
+    private static Employee[] arrayOfEmps = {
+        new Employee(1, "Jeff Bezos", 100000.0), 
+        new Employee(2, "Bill Gates", 200000.0), 
+        new Employee(3, "Mark Zuckerberg", 300000.0)
+    };
+
+    private static List<Employee> empList = Arrays.asList(arrayOfEmps);
+    private static EmployeeRepository employeeRepository = new EmployeeRepository(empList);
+
+    @After
+    public void cleanup() throws IOException {
+        Files.deleteIfExists(Paths.get(fileName));
+    }
+    
+    @Test
+    public void whenGetStreamFromList_ObtainStream() {
+        assert(empList.stream() instanceof Stream<?>);
+    }
+
+    @Test
+    public void whenGetStreamFromArray_ObtainStream() {
+        assert(Stream.of(arrayOfEmps) instanceof Stream<?>);
+    }
+
+    @Test
+    public void whenGetStreamFromElements_ObtainStream() {
+        assert(Stream.of(arrayOfEmps[0], arrayOfEmps[1], arrayOfEmps[2]) instanceof Stream<?>);
+    }
+
+    @Test
+    public void whenBuildStreamFromElements_ObtainStream() {
+        Stream.Builder<Employee> empStreamBuilder = Stream.builder();
+        
+        empStreamBuilder.accept(arrayOfEmps[0]);
+        empStreamBuilder.accept(arrayOfEmps[1]);
+        empStreamBuilder.accept(arrayOfEmps[2]);
+
+        Stream<Employee> empStream = empStreamBuilder.build();
+        
+        assert(empStream instanceof Stream<?>);
+    }
+
+    @Test
+    public void whenIncrementSalaryForEachEmployee_thenApplyNewSalary() {
+        Employee[] arrayOfEmps = {
+            new Employee(1, "Jeff Bezos", 100000.0), 
+            new Employee(2, "Bill Gates", 200000.0), 
+            new Employee(3, "Mark Zuckerberg", 300000.0)
+        };
+
+        List<Employee> empList = Arrays.asList(arrayOfEmps);
+        
+        empList.stream().forEach(e -> e.salaryIncrement(10.0));
+        
+        assertThat(empList, contains(
+          hasProperty("salary", equalTo(110000.0)),
+          hasProperty("salary", equalTo(220000.0)),
+          hasProperty("salary", equalTo(330000.0))
+        ));
+    }
+
+    @Test
+    public void whenIncrementSalaryUsingPeek_thenApplyNewSalary() {
+        Employee[] arrayOfEmps = {
+            new Employee(1, "Jeff Bezos", 100000.0), 
+            new Employee(2, "Bill Gates", 200000.0), 
+            new Employee(3, "Mark Zuckerberg", 300000.0)
+        };
+
+        List<Employee> empList = Arrays.asList(arrayOfEmps);
+        
+        empList.stream()
+          .peek(e -> e.salaryIncrement(10.0))
+          .peek(System.out::println)
+          .collect(Collectors.toList());
+
+        assertThat(empList, contains(
+          hasProperty("salary", equalTo(110000.0)),
+          hasProperty("salary", equalTo(220000.0)),
+          hasProperty("salary", equalTo(330000.0))
+        ));
+    }
+
+    @Test
+    public void whenMapIdToEmployees_thenGetEmployeeStream() {
+        Integer[] empIds = { 1, 2, 3 };
+        
+        List<Employee> employees = Stream.of(empIds)
+          .map(employeeRepository::findById)
+          .collect(Collectors.toList());
+        
+        assertEquals(employees.size(), empIds.length);
+    }
+
+    @Test
+    public void whenFlatMapEmployeeNames_thenGetNameStream() {
+        List<List<String>> namesNested = Arrays.asList( 
+          Arrays.asList("Jeff", "Bezos"), 
+          Arrays.asList("Bill", "Gates"), 
+          Arrays.asList("Mark", "Zuckerberg"));
+
+        List<String> namesFlatStream = namesNested.stream()
+          .flatMap(Collection::stream)
+          .collect(Collectors.toList());
+
+        assertEquals(namesFlatStream.size(), namesNested.size() * 2);
+    }
+
+    @Test
+    public void whenFilterEmployees_thenGetFilteredStream() {
+        Integer[] empIds = { 1, 2, 3, 4 };
+        
+        List<Employee> employees = Stream.of(empIds)
+          .map(employeeRepository::findById)
+          .filter(e -> e != null)
+          .filter(e -> e.getSalary() > 200000)
+          .collect(Collectors.toList());
+        
+        assertEquals(Arrays.asList(arrayOfEmps[2]), employees);
+    }
+
+    @Test
+    public void whenFindFirst_thenGetFirstEmployeeInStream() {
+        Integer[] empIds = { 1, 2, 3, 4 };
+        
+        Employee employee = Stream.of(empIds)
+          .map(employeeRepository::findById)
+          .filter(e -> e != null)
+          .filter(e -> e.getSalary() > 100000)
+          .findFirst()
+          .orElse(null);
+        
+        assertEquals(employee.getSalary(), new Double(200000));
+    }
+
+    @Test
+    public void whenCollectStreamToList_thenGetList() {
+        List<Employee> employees = empList.stream().collect(Collectors.toList());
+        
+        assertEquals(empList, employees);
+    }
+
+    @Test
+    public void whenStreamToArray_thenGetArray() {
+        Employee[] employees = empList.stream().toArray(Employee[]::new);
+
+        assertThat(empList.toArray(), equalTo(employees));
+    }
+    
+    @Test
+    public void whenStreamCount_thenGetElementCount() {
+        Long empCount = empList.stream()
+          .filter(e -> e.getSalary() > 200000)
+          .count();
+
+        assertEquals(empCount, new Long(1));
+    }
+
+    @Test
+    public void whenLimitInfiniteStream_thenGetFiniteElements() {
+        Stream<Integer> infiniteStream = Stream.iterate(2, i -> i * 2);
+    
+        List<Integer> collect = infiniteStream
+          .skip(3)
+          .limit(5)
+          .collect(Collectors.toList());
+  
+        assertEquals(collect, Arrays.asList(16, 32, 64, 128, 256));
+    }
+    
+    @Test
+    public void whenSortStream_thenGetSortedStream() {
+        List<Employee> employees = empList.stream()
+          .sorted((e1, e2) -> e1.getName().compareTo(e2.getName()))
+          .collect(Collectors.toList());
+
+        assertEquals(employees.get(0).getName(), "Bill Gates");
+        assertEquals(employees.get(1).getName(), "Jeff Bezos");
+        assertEquals(employees.get(2).getName(), "Mark Zuckerberg");
+    }
+
+
+    @Test
+    public void whenFindMin_thenGetMinElementFromStream() {
+        Employee firstEmp = empList.stream()
+          .min((e1, e2) -> e1.getId() - e2.getId())
+          .orElseThrow(NoSuchElementException::new);
+
+        assertEquals(firstEmp.getId(), new Integer(1));
+    }
+    
+    @Test
+    public void whenFindMax_thenGetMaxElementFromStream() {
+        Employee maxSalEmp = empList.stream()
+          .max(Comparator.comparing(Employee::getSalary))
+          .orElseThrow(NoSuchElementException::new);
+
+        assertEquals(maxSalEmp.getSalary(), new Double(300000.0));
+    }
+    
+    @Test
+    public void whenApplyDistinct_thenRemoveDuplicatesFromStream() {
+        List<Integer> intList = Arrays.asList(2, 5, 3, 2, 4, 3);
+        List<Integer> distinctIntList = intList.stream().distinct().collect(Collectors.toList());
+        
+        assertEquals(distinctIntList, Arrays.asList(2, 5, 3, 4));
+    }
+
+    @Test
+    public void whenApplyMatch_thenReturnBoolean() {
+        List<Integer> intList = Arrays.asList(2, 4, 5, 6, 8);
+        
+        boolean allEven = intList.stream().allMatch(i -> i % 2 == 0);
+        boolean oneEven = intList.stream().anyMatch(i -> i % 2 == 0);
+        boolean noneMultipleOfThree = intList.stream().noneMatch(i -> i % 3 == 0);
+        
+        assertEquals(allEven, false);
+        assertEquals(oneEven, true);
+        assertEquals(noneMultipleOfThree, false);
+    }
+    
+    @Test
+    public void whenFindMaxOnIntStream_thenGetMaxInteger() {
+        Integer latestEmpId = empList.stream()
+          .mapToInt(Employee::getId)
+          .max()
+          .orElseThrow(NoSuchElementException::new);
+
+        assertEquals(latestEmpId, new Integer(3));
+    }
+
+    @Test
+    public void whenApplySumOnIntStream_thenGetSum() {
+        Double avgSal = empList.stream()
+          .mapToDouble(Employee::getSalary)
+          .average()
+          .orElseThrow(NoSuchElementException::new);
+        
+        assertEquals(avgSal, new Double(200000));
+    }
+    
+    @Test
+    public void whenApplyReduceOnStream_thenGetValue() {
+        Double sumSal = empList.stream()
+          .map(Employee::getSalary)
+          .reduce(0.0, Double::sum);
+
+        assertEquals(sumSal, new Double(600000));
+    }
+    
+    @Test
+    public void whenCollectByJoining_thenGetJoinedString() {
+        String empNames = empList.stream()
+          .map(Employee::getName)
+          .collect(Collectors.joining(", "))
+          .toString();
+        
+        assertEquals(empNames, "Jeff Bezos, Bill Gates, Mark Zuckerberg");
+    }
+    
+    @Test
+    public void whenCollectBySet_thenGetSet() {
+        Set<String> empNames = empList.stream()
+                .map(Employee::getName)
+                .collect(Collectors.toSet());
+        
+        assertEquals(empNames.size(), 3);
+    }
+    
+    @Test
+    public void whenToVectorCollection_thenGetVector() {
+        Vector<String> empNames = empList.stream()
+                .map(Employee::getName)
+                .collect(Collectors.toCollection(Vector::new));
+        
+        assertEquals(empNames.size(), 3);
+    }
+
+    @Test
+    public void whenApplySummarizing_thenGetBasicStats() {
+        DoubleSummaryStatistics stats = empList.stream()
+          .collect(Collectors.summarizingDouble(Employee::getSalary));
+
+        assertEquals(stats.getCount(), 3);
+        assertEquals(stats.getSum(), 600000.0, 0);
+        assertEquals(stats.getMin(), 100000.0, 0);
+        assertEquals(stats.getMax(), 300000.0, 0);
+        assertEquals(stats.getAverage(), 200000.0, 0);
+    }
+
+    @Test
+    public void whenApplySummaryStatistics_thenGetBasicStats() {
+        DoubleSummaryStatistics stats = empList.stream()
+          .mapToDouble(Employee::getSalary)
+          .summaryStatistics();
+
+        assertEquals(stats.getCount(), 3);
+        assertEquals(stats.getSum(), 600000.0, 0);
+        assertEquals(stats.getMin(), 100000.0, 0);
+        assertEquals(stats.getMax(), 300000.0, 0);
+        assertEquals(stats.getAverage(), 200000.0, 0);
+    }
+
+    @Test
+    public void whenStreamPartition_thenGetMap() {
+        List<Integer> intList = Arrays.asList(2, 4, 5, 6, 8);
+        Map<Boolean, List<Integer>> isEven = intList.stream().collect(
+          Collectors.partitioningBy(i -> i % 2 == 0));
+        
+        assertEquals(isEven.get(true).size(), 4);
+        assertEquals(isEven.get(false).size(), 1);
+    }
+    
+    @Test
+    public void whenStreamGroupingBy_thenGetMap() {
+        Map<Character, List<Employee>> groupByAlphabet = empList.stream().collect(
+          Collectors.groupingBy(e -> new Character(e.getName().charAt(0))));
+
+        assertEquals(groupByAlphabet.get('B').get(0).getName(), "Bill Gates");
+        assertEquals(groupByAlphabet.get('J').get(0).getName(), "Jeff Bezos");
+        assertEquals(groupByAlphabet.get('M').get(0).getName(), "Mark Zuckerberg");
+    }
+    
+    @Test
+    public void whenStreamMapping_thenGetMap() {
+        Map<Character, List<Integer>> idGroupedByAlphabet = empList.stream().collect(
+          Collectors.groupingBy(e -> new Character(e.getName().charAt(0)),
+            Collectors.mapping(Employee::getId, Collectors.toList())));
+
+        assertEquals(idGroupedByAlphabet.get('B').get(0), new Integer(2));
+        assertEquals(idGroupedByAlphabet.get('J').get(0), new Integer(1));
+        assertEquals(idGroupedByAlphabet.get('M').get(0), new Integer(3));
+    }
+
+    @Test
+    public void whenStreamReducing_thenGetValue() {
+        Double percentage = 10.0;
+        Double salIncrOverhead = empList.stream().collect(Collectors.reducing(
+            0.0, e -> e.getSalary() * percentage / 100, (s1, s2) -> s1 + s2));
+
+        assertEquals(salIncrOverhead, 60000.0, 0);
+    }
+    
+    @Test
+    public void whenStreamGroupingAndReducing_thenGetMap() {
+        Comparator<Employee> byNameLength = Comparator.comparing(Employee::getName);
+        
+        Map<Character, Optional<Employee>> longestNameByAlphabet = empList.stream().collect(
+          Collectors.groupingBy(e -> new Character(e.getName().charAt(0)),
+            Collectors.reducing(BinaryOperator.maxBy(byNameLength))));
+
+        assertEquals(longestNameByAlphabet.get('B').get().getName(), "Bill Gates");
+        assertEquals(longestNameByAlphabet.get('J').get().getName(), "Jeff Bezos");
+        assertEquals(longestNameByAlphabet.get('M').get().getName(), "Mark Zuckerberg");
+    }
+
+    @Test
+    public void whenParallelStream_thenPerformOperationsInParallel() {
+        Employee[] arrayOfEmps = {
+          new Employee(1, "Jeff Bezos", 100000.0), 
+          new Employee(2, "Bill Gates", 200000.0), 
+          new Employee(3, "Mark Zuckerberg", 300000.0)
+        };
+
+        List<Employee> empList = Arrays.asList(arrayOfEmps);
+        
+        empList.stream().parallel().forEach(e -> e.salaryIncrement(10.0));
+        
+        assertThat(empList, contains(
+          hasProperty("salary", equalTo(110000.0)),
+          hasProperty("salary", equalTo(220000.0)),
+          hasProperty("salary", equalTo(330000.0))
+        ));
+    }
+
+    @Test
+    public void whenGenerateStream_thenGetInfiniteStream() {
+        Stream.generate(Math::random)
+          .limit(5)
+          .forEach(System.out::println);
+    }
+
+    @Test
+    public void whenIterateStream_thenGetInfiniteStream() {
+        Stream<Integer> evenNumStream = Stream.iterate(2, i -> i * 2);
+    
+        List<Integer> collect = evenNumStream
+          .limit(5)
+          .collect(Collectors.toList());
+  
+        assertEquals(collect, Arrays.asList(2, 4, 8, 16, 32));
+    }
+
+    @Test
+    public void whenStreamToFile_thenGetFile() throws IOException {
+        String[] words = {
+          "hello", 
+          "refer",
+          "world",
+          "level"
+        };
+        
+        try (PrintWriter pw = new PrintWriter(
+          Files.newBufferedWriter(Paths.get(fileName)))) {
+            Stream.of(words).forEach(pw::println);
+        }
+    }
+    
+    private List<String> getPalindrome(Stream<String> stream, int length) {
+        return stream.filter(s -> s.length() == length)
+          .filter(s -> s.compareToIgnoreCase(
+            new StringBuilder(s).reverse().toString()) == 0)
+          .collect(Collectors.toList());
+    }
+    
+    @Test
+    public void whenFileToStream_thenGetStream() throws IOException {
+        whenStreamToFile_thenGetFile();
+        
+        List<String> str = getPalindrome(Files.lines(Paths.get(fileName)), 5);        
+        assertThat(str, contains("refer", "level"));
+    }
+}
diff --git a/guest/core-java/src/test/resources/.keep b/guest/core-java/src/test/resources/.keep
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/hibernate5/src/main/java/com/baeldung/hibernate/converters/PersonNameConverter.java b/hibernate5/src/main/java/com/baeldung/hibernate/converters/PersonNameConverter.java
index c8b3397b09..506e674984 100644
--- a/hibernate5/src/main/java/com/baeldung/hibernate/converters/PersonNameConverter.java
+++ b/hibernate5/src/main/java/com/baeldung/hibernate/converters/PersonNameConverter.java
@@ -11,31 +11,49 @@ public class PersonNameConverter implements AttributeConverter<PersonName, Strin
     private static final String SEPARATOR = ", ";
 
     @Override
-    public String convertToDatabaseColumn(PersonName person) {
+    public String convertToDatabaseColumn(PersonName personName) {
+        if (personName == null) {
+            return null;
+        }
+
         StringBuilder sb = new StringBuilder();
-        if (person.getSurname() != null) {
-            sb.append(person.getSurname());
+        if (personName.getSurname() != null && !personName.getSurname()
+            .isEmpty()) {
+            sb.append(personName.getSurname());
             sb.append(SEPARATOR);
         }
 
-        if (person.getName() != null) {
-            sb.append(person.getName());
+        if (personName.getName() != null && !personName.getName()
+            .isEmpty()) {
+            sb.append(personName.getName());
         }
 
         return sb.toString();
     }
 
     @Override
-    public PersonName convertToEntityAttribute(String dbPerson) {
-        String[] pieces = dbPerson.split(SEPARATOR);
-
-        if (pieces == null || pieces.length != 2) {
+    public PersonName convertToEntityAttribute(String dbPersonName) {
+        if (dbPersonName == null || dbPersonName.isEmpty()) {
             return null;
         }
 
-        PersonName personName = new PersonName();
-        personName.setSurname(pieces[0]);
-        personName.setName(pieces[1]);
+        String[] pieces = dbPersonName.split(SEPARATOR);
+
+        if (pieces == null || pieces.length == 0) {
+            return null;
+        }
+
+        PersonName personName = new PersonName();        
+        String firstPiece = !pieces[0].isEmpty() ? pieces[0] : null;
+        if (dbPersonName.contains(SEPARATOR)) {
+            personName.setSurname(firstPiece);
+
+            if (pieces.length >= 2 && pieces[1] != null && !pieces[1].isEmpty()) {
+                personName.setName(pieces[1]);
+            }
+        } else {
+            personName.setName(firstPiece);
+        }
 
         return personName;
     }
diff --git a/hibernate5/src/test/java/com/baeldung/hibernate/converter/PersonNameConverterTest.java b/hibernate5/src/test/java/com/baeldung/hibernate/converter/PersonNameConverterTest.java
index aec2311294..204d8775ff 100644
--- a/hibernate5/src/test/java/com/baeldung/hibernate/converter/PersonNameConverterTest.java
+++ b/hibernate5/src/test/java/com/baeldung/hibernate/converter/PersonNameConverterTest.java
@@ -71,4 +71,130 @@ public class PersonNameConverterTest {
             .getSurname(), surname);
     }
 
+    @Test
+    public void givenPersonNameNull_WhenSaving_ThenNullStored() {
+        final String name = null;
+        final String surname = null;
+
+        PersonName personName = new PersonName();
+        personName.setName(name);
+        personName.setSurname(surname);
+
+        Person person = new Person();
+        person.setPersonName(personName);
+
+        Long id = (Long) session.save(person);
+
+        session.flush();
+        session.clear();
+
+        String dbPersonName = (String) session.createNativeQuery("select p.personName from PersonTable p where p.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals("", dbPersonName);
+
+        Person dbPerson = session.createNativeQuery("select * from PersonTable p where p.id = :id", Person.class)
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals(dbPerson.getPersonName(), null);
+    }
+
+    @Test
+    public void givenPersonNameWithoutName_WhenSaving_ThenNotNameStored() {
+        final String name = null;
+        final String surname = "surname";
+
+        PersonName personName = new PersonName();
+        personName.setName(name);
+        personName.setSurname(surname);
+
+        Person person = new Person();
+        person.setPersonName(personName);
+
+        Long id = (Long) session.save(person);
+
+        session.flush();
+        session.clear();
+
+        String dbPersonName = (String) session.createNativeQuery("select p.personName from PersonTable p where p.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals("surname, ", dbPersonName);
+
+        Person dbPerson = session.createNativeQuery("select * from PersonTable p where p.id = :id", Person.class)
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals(dbPerson.getPersonName()
+            .getName(), name);
+        assertEquals(dbPerson.getPersonName()
+            .getSurname(), surname);
+    }
+
+    @Test
+    public void givenPersonNameWithoutSurName_WhenSaving_ThenNotSurNameStored() {
+        final String name = "name";
+        final String surname = null;
+
+        PersonName personName = new PersonName();
+        personName.setName(name);
+        personName.setSurname(surname);
+
+        Person person = new Person();
+        person.setPersonName(personName);
+
+        Long id = (Long) session.save(person);
+
+        session.flush();
+        session.clear();
+
+        String dbPersonName = (String) session.createNativeQuery("select p.personName from PersonTable p where p.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals("name", dbPersonName);
+
+        Person dbPerson = session.createNativeQuery("select * from PersonTable p where p.id = :id", Person.class)
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals(dbPerson.getPersonName()
+            .getName(), name);
+        assertEquals(dbPerson.getPersonName()
+            .getSurname(), surname);
+    }
+
+    @Test
+    public void givenPersonNameEmptyFields_WhenSaving_ThenFielsNotStored() {
+        final String name = "";
+        final String surname = "";
+
+        PersonName personName = new PersonName();
+        personName.setName(name);
+        personName.setSurname(surname);
+
+        Person person = new Person();
+        person.setPersonName(personName);
+
+        Long id = (Long) session.save(person);
+
+        session.flush();
+        session.clear();
+
+        String dbPersonName = (String) session.createNativeQuery("select p.personName from PersonTable p where p.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals("", dbPersonName);
+
+        Person dbPerson = session.createNativeQuery("select * from PersonTable p where p.id = :id", Person.class)
+            .setParameter("id", id)
+            .getSingleResult();
+
+        assertEquals(dbPerson.getPersonName(), null);
+    }
+
 }
diff --git a/java-lite/pom.xml b/java-lite/pom.xml
index eb18bc40a5..d7950487ca 100644
--- a/java-lite/pom.xml
+++ b/java-lite/pom.xml
@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
 
     <groupId>org.baeldung</groupId>
@@ -22,10 +21,15 @@
         <mysql.connector.java.version>5.1.45</mysql.connector.java.version>
         <sun.tools.version>1.7.0</sun.tools.version>
         <jackson.version>1.8.2</jackson.version>
-        <junit.version>4.11</junit.version>
+        <junit.version>4.12</junit.version>
     </properties>
 
     <build>
+        <resources>
+            <resource>
+                <directory>src/main/webapp/WEB-INF</directory>
+            </resource>
+        </resources>
         <plugins>
             <plugin>
                 <groupId>org.eclipse.jetty</groupId>
@@ -85,7 +89,14 @@
             <scope>system</scope>
             <systemPath>${java.home}/../lib/tools.jar</systemPath>
         </dependency>
-
+        
+        <dependency>
+            <groupId>org.javalite</groupId>
+            <artifactId>activeweb-testing</artifactId>
+            <version>1.15</version>
+            <scope>test</scope>
+        </dependency>
+        
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
diff --git a/java-lite/src/main/java/app/config/AppBootstrap.java b/java-lite/src/main/java/app/config/AppBootstrap.java
index 7a87c2d0a7..02c8360986 100644
--- a/java-lite/src/main/java/app/config/AppBootstrap.java
+++ b/java-lite/src/main/java/app/config/AppBootstrap.java
@@ -3,7 +3,15 @@ package app.config;
 import org.javalite.activeweb.AppContext;
 import org.javalite.activeweb.Bootstrap;
 
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+
+import app.services.ArticleServiceModule;
+
 public class AppBootstrap extends Bootstrap {
     public void init(AppContext context) {
     }
+    public Injector getInjector() {
+        return Guice.createInjector(new ArticleServiceModule());
+    }
 }
diff --git a/java-lite/src/main/java/app/controllers/ArticleController.java b/java-lite/src/main/java/app/controllers/ArticleController.java
new file mode 100755
index 0000000000..2b8dc452bd
--- /dev/null
+++ b/java-lite/src/main/java/app/controllers/ArticleController.java
@@ -0,0 +1,28 @@
+package app.controllers;
+
+import javax.inject.Inject;
+
+import org.javalite.activeweb.AppController;
+
+import app.services.ArticleService;
+
+public class ArticleController extends AppController {
+
+    @Inject
+    private ArticleService articleService;
+
+    public void index() {
+        view("articles", articleService.getArticles());
+    }
+
+    public void search() {
+
+        String keyword = param("key");
+        if (null != keyword) {
+            assign("article", articleService.search(keyword));
+        } else {
+            render("/common/error");
+        }
+
+    }
+}
diff --git a/java-lite/src/main/java/app/controllers/HomeController.java b/java-lite/src/main/java/app/controllers/HomeController.java
new file mode 100755
index 0000000000..0e284af0ad
--- /dev/null
+++ b/java-lite/src/main/java/app/controllers/HomeController.java
@@ -0,0 +1,11 @@
+package app.controllers;
+
+import org.javalite.activeweb.AppController;
+
+public class HomeController extends AppController {
+
+    public void index() {
+        render("index");
+    }
+
+}
diff --git a/java-lite/src/main/java/app/models/Article.java b/java-lite/src/main/java/app/models/Article.java
new file mode 100755
index 0000000000..db318f4468
--- /dev/null
+++ b/java-lite/src/main/java/app/models/Article.java
@@ -0,0 +1,50 @@
+package app.models;
+
+public class Article {
+
+    private String title;
+    private String author;
+    private String words;
+    private String date;
+
+    public Article(String title, String author, String words, String date) {
+        super();
+        this.title = title;
+        this.author = author;
+        this.words = words;
+        this.date = date;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public String getWords() {
+        return words;
+    }
+
+    public void setWords(String words) {
+        this.words = words;
+    }
+
+    public String getDate() {
+        return date;
+    }
+
+    public void setDate(String date) {
+        this.date = date;
+    }
+
+}
\ No newline at end of file
diff --git a/java-lite/src/main/java/app/services/ArticleService.java b/java-lite/src/main/java/app/services/ArticleService.java
new file mode 100755
index 0000000000..ddd0b3ed10
--- /dev/null
+++ b/java-lite/src/main/java/app/services/ArticleService.java
@@ -0,0 +1,13 @@
+package app.services;
+
+import java.util.List;
+
+import app.models.Article;
+
+public interface ArticleService {
+
+    List<Article> getArticles();
+
+    Article search(String keyword);
+
+}
diff --git a/java-lite/src/main/java/app/services/ArticleServiceImpl.java b/java-lite/src/main/java/app/services/ArticleServiceImpl.java
new file mode 100755
index 0000000000..fc81576f91
--- /dev/null
+++ b/java-lite/src/main/java/app/services/ArticleServiceImpl.java
@@ -0,0 +1,34 @@
+package app.services;
+
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
+
+import app.models.Article;
+
+public class ArticleServiceImpl implements ArticleService {
+
+    public List<Article> getArticles() {
+        return fetchArticles();
+    }
+
+    public Article search(String keyword) {
+        Article ar = new Article("Article with " + keyword, "baeldung", "1250", Instant.now()
+            .toString());
+        return ar;
+    }
+
+    private List<Article> fetchArticles() {
+        Article ar1 = new Article("Introduction to ActiveWeb", "baeldung", "1650", Instant.now()
+            .toString());
+
+        Article ar = new Article("Introduction to Mule", "baeldung", "1650", Instant.now()
+            .toString());
+        List<Article> articles = new ArrayList<Article>();
+        articles.add(ar);
+        articles.add(ar1);
+        return articles;
+
+    }
+
+}
diff --git a/java-lite/src/main/java/app/services/ArticleServiceModule.java b/java-lite/src/main/java/app/services/ArticleServiceModule.java
new file mode 100755
index 0000000000..feae2a2ff7
--- /dev/null
+++ b/java-lite/src/main/java/app/services/ArticleServiceModule.java
@@ -0,0 +1,12 @@
+package app.services;
+
+import com.google.inject.AbstractModule;
+
+public class ArticleServiceModule extends AbstractModule {
+
+    @Override
+    protected void configure() {
+        bind(ArticleService.class).to(ArticleServiceImpl.class)
+            .asEagerSingleton();
+    }
+}
diff --git a/java-lite/src/main/webapp/WEB-INF/views/article/index.ftl b/java-lite/src/main/webapp/WEB-INF/views/article/index.ftl
new file mode 100755
index 0000000000..2d5f211427
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/article/index.ftl
@@ -0,0 +1,18 @@
+<@content for="title">Articles</@content>
+
+<table>
+    <tr>
+        <td>Title</td>
+        <td>Author</td>
+        <td>Words #</td>
+        <td>Date Published</td>
+    </tr>
+<#list articles as article>
+    <tr>
+        <td>${article.title}</td>
+        <td>${article.author}</td>
+        <td>${article.words}</td>
+        <td>${article.date}</td>
+    </tr>
+</#list>
+</table>
\ No newline at end of file
diff --git a/java-lite/src/main/webapp/WEB-INF/views/article/search.ftl b/java-lite/src/main/webapp/WEB-INF/views/article/search.ftl
new file mode 100755
index 0000000000..45a73808ed
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/article/search.ftl
@@ -0,0 +1,17 @@
+<@content for="title">Search</@content>
+
+<table>
+    <tr>
+        <td>Title</td>
+        <td>Author</td>
+        <td>Words #</td>
+        <td>Date Published</td>
+    </tr>
+    <tr>
+        <td>${article.title}</td>
+        <td>${article.author}</td>
+        <td>${article.words}</td>
+        <td>${article.date}</td>
+    </tr>
+
+</table>
\ No newline at end of file
diff --git a/java-lite/src/main/webapp/WEB-INF/views/common/error.ftl b/java-lite/src/main/webapp/WEB-INF/views/common/error.ftl
new file mode 100755
index 0000000000..5fbf3c5243
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/common/error.ftl
@@ -0,0 +1,3 @@
+<@content for="title">Simple Web App</@content>
+
+<h2>Application error</h2>
diff --git a/java-lite/src/main/webapp/WEB-INF/views/home/index.ftl b/java-lite/src/main/webapp/WEB-INF/views/home/index.ftl
new file mode 100755
index 0000000000..ae6a7c56a5
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/home/index.ftl
@@ -0,0 +1,3 @@
+<@content for="title">Simple Web App</@content>
+
+<h2>Baeldung ActiveWeb Demo Application</h2>
diff --git a/java-lite/src/main/webapp/WEB-INF/views/layouts/default_layout.ftl b/java-lite/src/main/webapp/WEB-INF/views/layouts/default_layout.ftl
new file mode 100755
index 0000000000..2985e56278
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/layouts/default_layout.ftl
@@ -0,0 +1,16 @@
+<#setting url_escaping_charset='ISO-8859-1'>
+<html>
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
+</head>
+<body>
+
+<div class="main">
+<#include "header.ftl" >
+    <div class="content">
+    ${page_content}
+    </div>
+<#include "footer.ftl" >
+</div>
+</body>
+</html>
diff --git a/java-lite/src/main/webapp/WEB-INF/views/layouts/footer.ftl b/java-lite/src/main/webapp/WEB-INF/views/layouts/footer.ftl
new file mode 100755
index 0000000000..1408547424
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/layouts/footer.ftl
@@ -0,0 +1,3 @@
+<div class='footer'>
+    <p>2018 Baeldung. No Rights Reserved.</p>
+</div>
diff --git a/java-lite/src/main/webapp/WEB-INF/views/layouts/header.ftl b/java-lite/src/main/webapp/WEB-INF/views/layouts/header.ftl
new file mode 100755
index 0000000000..8187435035
--- /dev/null
+++ b/java-lite/src/main/webapp/WEB-INF/views/layouts/header.ftl
@@ -0,0 +1,4 @@
+<div class="header">
+    <h1><a href="${context_path}">Baeldung ActiveWeb Demo</a></h1>
+</div>
+
diff --git a/java-lite/src/main/webapp/WEB-INF/web.xml b/java-lite/src/main/webapp/WEB-INF/web.xml
index c285876c86..23bb8b865e 100644
--- a/java-lite/src/main/webapp/WEB-INF/web.xml
+++ b/java-lite/src/main/webapp/WEB-INF/web.xml
@@ -6,6 +6,10 @@
     <filter>
         <filter-name>dispatcher</filter-name>
         <filter-class>org.javalite.activeweb.RequestDispatcher</filter-class>
+        <init-param>
+            <param-name>root_controller</param-name>
+            <param-value>home</param-value>
+        </init-param>
         <init-param>
             <param-name>exclusions</param-name>
             <param-value>css,images,js,ico</param-value>
diff --git a/java-lite/src/test/java/app/controllers/ArticleControllerSpec.java b/java-lite/src/test/java/app/controllers/ArticleControllerSpec.java
new file mode 100755
index 0000000000..882441dad3
--- /dev/null
+++ b/java-lite/src/test/java/app/controllers/ArticleControllerSpec.java
@@ -0,0 +1,31 @@
+package app.controllers;
+
+import org.javalite.activeweb.ControllerSpec;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.google.inject.Guice;
+
+import app.services.ArticleServiceModule;
+
+public class ArticleControllerSpec extends ControllerSpec {
+
+    @Before
+    public void before() {
+        setInjector(Guice.createInjector(new ArticleServiceModule()));
+    }
+
+    @Test
+    public void whenReturnedArticlesThenCorrect() {
+        request().get("index");
+        a(responseContent()).shouldContain("<td>Introduction to Mule</td>");
+    }
+
+    @Test
+    public void givenKeywordWhenFoundArticleThenCorrect() {
+        request().param("key", "Java")
+            .get("search");
+        a(responseContent()).shouldContain("<td>Article with Java</td>");
+    }
+
+}
diff --git a/javax-servlets/src/main/java/com/baeldung/controller/StudentServlet.java b/javax-servlets/src/main/java/com/baeldung/controller/StudentServlet.java
new file mode 100644
index 0000000000..b1924198a4
--- /dev/null
+++ b/javax-servlets/src/main/java/com/baeldung/controller/StudentServlet.java
@@ -0,0 +1,39 @@
+package com.baeldung.controller;
+
+import com.baeldung.service.StudentService;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletException;
+import javax.servlet.annotation.WebServlet;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+
+@WebServlet(name = "StudentServlet", urlPatterns = "/student-record")
+public class StudentServlet extends HttpServlet {
+
+    private final StudentService studentService = new StudentService();
+
+    private void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        String studentID = request.getParameter("id");
+        if (studentID != null) {
+            int id = Integer.parseInt(studentID);
+            studentService.getStudent(id)
+              .ifPresent(s -> request.setAttribute("studentRecord", s));
+        }
+
+        RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/jsp/student-record.jsp");
+        dispatcher.forward(request, response);
+    }
+
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        processRequest(request, response);
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        processRequest(request, response);
+    }
+}
diff --git a/javax-servlets/src/main/java/com/baeldung/model/Student.java b/javax-servlets/src/main/java/com/baeldung/model/Student.java
new file mode 100644
index 0000000000..ce8a27375a
--- /dev/null
+++ b/javax-servlets/src/main/java/com/baeldung/model/Student.java
@@ -0,0 +1,39 @@
+package com.baeldung.model;
+
+public class Student {
+
+    private int id;
+    private String firstName;
+    private String lastName;
+
+    public Student(int id, String firstName, String lastName) {
+        super();
+        this.id = id;
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+}
diff --git a/javax-servlets/src/main/java/com/baeldung/service/StudentService.java b/javax-servlets/src/main/java/com/baeldung/service/StudentService.java
new file mode 100644
index 0000000000..525d47683f
--- /dev/null
+++ b/javax-servlets/src/main/java/com/baeldung/service/StudentService.java
@@ -0,0 +1,21 @@
+package com.baeldung.service;
+
+import com.baeldung.model.Student;
+
+import java.util.Optional;
+
+public class StudentService {
+
+    public Optional<Student> getStudent(int id) {
+        switch (id) {
+            case 1:
+                return Optional.of(new Student(1, "John", "Doe"));
+            case 2:
+                return Optional.of(new Student(2, "Jane", "Goodall"));
+            case 3:
+                return Optional.of(new Student(3, "Max", "Born"));
+            default:
+                return Optional.empty();
+        }
+    }
+}
diff --git a/javax-servlets/src/main/java/com/baeldung/servlets/FormServlet.java b/javax-servlets/src/main/java/com/baeldung/servlets/FormServlet.java
index fcd9143dff..c78129a9cf 100644
--- a/javax-servlets/src/main/java/com/baeldung/servlets/FormServlet.java
+++ b/javax-servlets/src/main/java/com/baeldung/servlets/FormServlet.java
@@ -1,7 +1,6 @@
 package com.baeldung.servlets;
 
 import javax.servlet.RequestDispatcher;
-import javax.servlet.ServletException;
 import javax.servlet.annotation.WebServlet;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
@@ -13,7 +12,7 @@ public class FormServlet extends HttpServlet {
 
     @Override
     protected void doPost(HttpServletRequest request, HttpServletResponse response)
-            throws ServletException, IOException {
+      throws IOException {
 
         String height = request.getParameter("height");
         String weight = request.getParameter("weight");
@@ -25,23 +24,20 @@ public class FormServlet extends HttpServlet {
             response.setHeader("Test", "Success");
             response.setHeader("BMI", String.valueOf(bmi));
 
-            RequestDispatcher dispatcher = request.getRequestDispatcher("index.jsp");
+            RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/jsp/index.jsp");
             dispatcher.forward(request, response);
         } catch (Exception e) {
-
             response.sendRedirect("index.jsp");
         }
     }
 
     @Override
-    protected void doGet(HttpServletRequest request, HttpServletResponse response)
-            throws ServletException, IOException {
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) {
 
         // do something else here
     }
 
     private Double calculateBMI(Double weight, Double height) {
-
         return weight / (height * height);
     }
 }
\ No newline at end of file
diff --git a/javax-servlets/web/index.jsp b/javax-servlets/src/main/webapp/WEB-INF/jsp/index.jsp
similarity index 100%
rename from javax-servlets/web/index.jsp
rename to javax-servlets/src/main/webapp/WEB-INF/jsp/index.jsp
diff --git a/javax-servlets/src/main/webapp/WEB-INF/jsp/student-record.jsp b/javax-servlets/src/main/webapp/WEB-INF/jsp/student-record.jsp
new file mode 100644
index 0000000000..4b9d9b378f
--- /dev/null
+++ b/javax-servlets/src/main/webapp/WEB-INF/jsp/student-record.jsp
@@ -0,0 +1,36 @@
+<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
+    pageEncoding="ISO-8859-1"%>
+
+<%@ page import="com.baeldung.model.Student"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>Student Record</title>
+</head>
+<body>
+    <%
+        if (request.getAttribute("studentRecord") != null) {
+            Student student = (Student) request.getAttribute("studentRecord");
+    %>
+
+    <h1>Student Record</h1>
+    <div>
+        ID:
+        <%=student.getId()%></div>
+    <div>
+        First Name:
+        <%=student.getFirstName()%></div>
+    <div>
+        Last Name:
+        <%=student.getLastName()%></div>
+
+    <%
+        } else {
+    %>
+    <h1>No student record found.</h1>
+    <%
+        }
+    %>
+</body>
+</html>
\ No newline at end of file
diff --git a/javax-servlets/web/WEB-INF/web.xml b/javax-servlets/src/main/webapp/WEB-INF/web.xml
similarity index 100%
rename from javax-servlets/web/WEB-INF/web.xml
rename to javax-servlets/src/main/webapp/WEB-INF/web.xml
diff --git a/jsonld/.gitignore b/jsonld/.gitignore
new file mode 100644
index 0000000000..2af7cefb0a
--- /dev/null
+++ b/jsonld/.gitignore
@@ -0,0 +1,24 @@
+target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+nbproject/private/
+build/
+nbbuild/
+dist/
+nbdist/
+.nb-gradle/
\ No newline at end of file
diff --git a/jsonld/.mvn/wrapper/maven-wrapper.jar b/jsonld/.mvn/wrapper/maven-wrapper.jar
new file mode 100644
index 0000000000..5fd4d5023f
Binary files /dev/null and b/jsonld/.mvn/wrapper/maven-wrapper.jar differ
diff --git a/jsonld/.mvn/wrapper/maven-wrapper.properties b/jsonld/.mvn/wrapper/maven-wrapper.properties
new file mode 100644
index 0000000000..c954cec91c
--- /dev/null
+++ b/jsonld/.mvn/wrapper/maven-wrapper.properties
@@ -0,0 +1 @@
+distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.9/apache-maven-3.3.9-bin.zip
diff --git a/jsonld/README.md b/jsonld/README.md
new file mode 100644
index 0000000000..51ca961bea
--- /dev/null
+++ b/jsonld/README.md
@@ -0,0 +1,22 @@
+JSON-LD
+=======
+
+Hypermedia serialization with JSON-LD.
+
+### Requirements
+
+- Maven
+- JDK 8
+- JSON-LD
+
+### Running
+To build and start the server simply type
+
+```bash
+$ mvn clean install
+$ mvn spring-boot:run
+```
+
+Now with default configurations it will be available at: [http://localhost:8080](http://localhost:8080)
+
+Enjoy it :)
\ No newline at end of file
diff --git a/jsonld/mvnw b/jsonld/mvnw
new file mode 100755
index 0000000000..a1ba1bf554
--- /dev/null
+++ b/jsonld/mvnw
@@ -0,0 +1,233 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+           #
+           # Look for the Apple JDKs first to preserve the existing behaviour, and then look
+           # for the new JDKs provided by Oracle.
+           #
+           if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK ] ; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -L /System/Library/Java/JavaVirtualMachines/CurrentJDK ] ; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=/System/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -L "/Library/Java/JavaVirtualMachines/CurrentJDK" ] ; then
+             #
+             # Oracle JDKs
+             #
+             export JAVA_HOME=/Library/Java/JavaVirtualMachines/CurrentJDK/Contents/Home
+           fi
+
+           if [ -z "$JAVA_HOME" ] && [ -x "/usr/libexec/java_home" ]; then
+             #
+             # Apple JDKs
+             #
+             export JAVA_HOME=`/usr/libexec/java_home`
+           fi
+           ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Migwn, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+  # TODO classpath?
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+fi
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+  local basedir=$(pwd)
+  local wdir=$(pwd)
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    wdir=$(cd "$wdir/.."; pwd)
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-$(find_maven_basedir)}
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} "$@"
diff --git a/jsonld/mvnw.cmd b/jsonld/mvnw.cmd
new file mode 100644
index 0000000000..2b934e89dd
--- /dev/null
+++ b/jsonld/mvnw.cmd
@@ -0,0 +1,145 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven2 Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+set MAVEN_CMD_LINE_ARGS=%*
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+
+set WRAPPER_JAR="".\.mvn\wrapper\maven-wrapper.jar""
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CMD_LINE_ARGS%
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%
\ No newline at end of file
diff --git a/jsonld/pom.xml b/jsonld/pom.xml
new file mode 100644
index 0000000000..1574878667
--- /dev/null
+++ b/jsonld/pom.xml
@@ -0,0 +1,53 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>jsonld</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <packaging>jar</packaging>
+
+    <name>jsonld</name>
+    <description>Hypermedia serialization with JSON-LD</description>
+
+    <parent>
+        <artifactId>parent-boot-5</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-boot-5</relativePath>
+    </parent>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <java.version>1.8</java.version>
+        <jsonld.version>0.11.1</jsonld.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>com.github.jsonld-java</groupId>
+            <artifactId>jsonld-java</artifactId>
+            <version>${jsonld.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>
diff --git a/jsonld/src/main/java/com/baeldung/JsonLdApplication.java b/jsonld/src/main/java/com/baeldung/JsonLdApplication.java
new file mode 100644
index 0000000000..0b8f338127
--- /dev/null
+++ b/jsonld/src/main/java/com/baeldung/JsonLdApplication.java
@@ -0,0 +1,11 @@
+package com.baeldung;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class JsonLdApplication {
+	public static void main(String[] args) {
+		SpringApplication.run(JsonLdApplication.class, args);
+	}
+}
diff --git a/jsonld/src/main/resources/application.properties b/jsonld/src/main/resources/application.properties
new file mode 100644
index 0000000000..b6bfd8f6f3
--- /dev/null
+++ b/jsonld/src/main/resources/application.properties
@@ -0,0 +1,14 @@
+# the db host
+spring.data.mongodb.host=localhost
+# the connection port (defaults to 27107)
+spring.data.mongodb.port=27017
+# The database's name
+spring.data.mongodb.database=Jenkins-Pipeline
+
+# Or this
+# spring.data.mongodb.uri=mongodb://localhost/Jenkins-Pipeline
+
+# spring.data.mongodb.username=
+# spring.data.mongodb.password=
+
+spring.data.mongodb.repositories.enabled=true
\ No newline at end of file
diff --git a/jsonld/src/test/java/com/baeldung/JsonLdSerializatorTest.java b/jsonld/src/test/java/com/baeldung/JsonLdSerializatorTest.java
new file mode 100644
index 0000000000..762a4254dc
--- /dev/null
+++ b/jsonld/src/test/java/com/baeldung/JsonLdSerializatorTest.java
@@ -0,0 +1,33 @@
+package com.baeldung;
+
+import com.github.jsonldjava.core.JsonLdError;
+import com.github.jsonldjava.core.JsonLdOptions;
+import com.github.jsonldjava.core.JsonLdProcessor;
+import com.github.jsonldjava.utils.JsonUtils;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.junit.Assert.assertNotEquals;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringBootTest
+public class JsonLdSerializatorTest {
+
+    @Test
+    public void whenInserting_andCount_thenWeDontGetZero() throws JsonLdError {
+        String inputStream = "{name:}";
+        Object jsonObject = JsonUtils.fromInputStream(inputStream);
+
+        Map context = new HashMap();
+        JsonLdOptions options = new JsonLdOptions();
+        Object compact = JsonLdProcessor.compact(jsonObject, context, options);
+
+        assertNotEquals(0, 0);
+    }
+
+}
diff --git a/libraries/helloWorld.docx b/libraries/helloWorld.docx
index 09e71a4d4e..6e0a372dad 100644
Binary files a/libraries/helloWorld.docx and b/libraries/helloWorld.docx differ
diff --git a/libraries/pom.xml b/libraries/pom.xml
index fa1839010c..64cc9c6a84 100644
--- a/libraries/pom.xml
+++ b/libraries/pom.xml
@@ -649,6 +649,11 @@
           <artifactId>google-http-client-gson</artifactId>
           <version>${googleclient.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.infinispan</groupId>
+            <artifactId>infinispan-core</artifactId>
+            <version>${infinispan.version}</version>
+        </dependency>
 
         <!--Java Docker API Client-->
         <dependency>
@@ -811,5 +816,6 @@
         <docker.version>3.0.14</docker.version>
         <tomcat.version>8.5.24</tomcat.version>
         <async.http.client.version>2.2.0</async.http.client.version>
+        <infinispan.version>9.1.5.Final</infinispan.version>
     </properties>
-</project>
\ No newline at end of file
+</project>
diff --git a/libraries/src/main/java/com/baeldung/infinispan/CacheConfiguration.java b/libraries/src/main/java/com/baeldung/infinispan/CacheConfiguration.java
new file mode 100644
index 0000000000..58929c0111
--- /dev/null
+++ b/libraries/src/main/java/com/baeldung/infinispan/CacheConfiguration.java
@@ -0,0 +1,84 @@
+package com.baeldung.infinispan;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import org.infinispan.Cache;
+import org.infinispan.configuration.cache.Configuration;
+import org.infinispan.configuration.cache.ConfigurationBuilder;
+import org.infinispan.eviction.EvictionType;
+import org.infinispan.manager.DefaultCacheManager;
+import org.infinispan.transaction.LockingMode;
+import org.infinispan.transaction.TransactionMode;
+
+import java.util.concurrent.TimeUnit;
+
+public class CacheConfiguration {
+
+    public static final String SIMPLE_HELLO_WORLD_CACHE = "simple-hello-world-cache";
+    public static final String EXPIRING_HELLO_WORLD_CACHE = "expiring-hello-world-cache";
+    public static final String EVICTING_HELLO_WORLD_CACHE = "evicting-hello-world-cache";
+    public static final String PASSIVATING_HELLO_WORLD_CACHE = "passivating-hello-world-cache";
+    public static final String TRANSACTIONAL_CACHE = "transactional-cache";
+
+    public DefaultCacheManager cacheManager() {
+        return new DefaultCacheManager();
+    }
+
+    public Cache<String, Integer> transactionalCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(TRANSACTIONAL_CACHE, cacheManager, listener, transactionalConfiguration());
+    }
+
+    public Cache<String, String> simpleHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(SIMPLE_HELLO_WORLD_CACHE, cacheManager, listener, new ConfigurationBuilder().build());
+    }
+
+    public Cache<String, String> expiringHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(EXPIRING_HELLO_WORLD_CACHE, cacheManager, listener, expiringConfiguration());
+    }
+
+    public Cache<String, String> evictingHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(EVICTING_HELLO_WORLD_CACHE, cacheManager, listener, evictingConfiguration());
+    }
+
+    public Cache<String, String> passivatingHelloWorldCache(DefaultCacheManager cacheManager, CacheListener listener) {
+        return this.buildCache(PASSIVATING_HELLO_WORLD_CACHE, cacheManager, listener, passivatingConfiguration());
+    }
+
+    private <K, V> Cache<K, V> buildCache(String cacheName, DefaultCacheManager cacheManager,
+      CacheListener listener, Configuration configuration) {
+
+        cacheManager.defineConfiguration(cacheName, configuration);
+        Cache<K, V> cache = cacheManager.getCache(cacheName);
+        cache.addListener(listener);
+        return cache;
+    }
+
+    private Configuration expiringConfiguration() {
+        return new ConfigurationBuilder().expiration().lifespan(1, TimeUnit.SECONDS)
+          .build();
+    }
+
+    private Configuration evictingConfiguration() {
+        return new ConfigurationBuilder()
+          .memory().evictionType(EvictionType.COUNT).size(1)
+          .build();
+    }
+
+    private Configuration passivatingConfiguration() {
+        return new ConfigurationBuilder()
+          .memory().evictionType(EvictionType.COUNT).size(1)
+          .persistence()
+          .passivation(true)
+          .addSingleFileStore()
+          .purgeOnStartup(true)
+          .location(System.getProperty("java.io.tmpdir"))
+          .build();
+    }
+
+    private Configuration transactionalConfiguration() {
+        return new ConfigurationBuilder()
+          .transaction().transactionMode(TransactionMode.TRANSACTIONAL)
+          .lockingMode(LockingMode.PESSIMISTIC)
+          .build();
+    }
+
+}
diff --git a/libraries/src/main/java/com/baeldung/infinispan/listener/CacheListener.java b/libraries/src/main/java/com/baeldung/infinispan/listener/CacheListener.java
new file mode 100644
index 0000000000..942a2fb62d
--- /dev/null
+++ b/libraries/src/main/java/com/baeldung/infinispan/listener/CacheListener.java
@@ -0,0 +1,53 @@
+package com.baeldung.infinispan.listener;
+
+import org.infinispan.notifications.Listener;
+import org.infinispan.notifications.cachelistener.annotation.*;
+import org.infinispan.notifications.cachelistener.event.*;
+
+@Listener
+public class CacheListener {
+
+    @CacheEntryCreated
+    public void entryCreated(CacheEntryCreatedEvent<String, String> event) {
+        this.printLog("Adding key '" + event.getKey() + "' to cache", event);
+    }
+
+    @CacheEntryExpired
+    public void entryExpired(CacheEntryExpiredEvent<String, String> event) {
+        this.printLog("Expiring key '" + event.getKey() + "' from cache", event);
+    }
+
+    @CacheEntryVisited
+    public void entryVisited(CacheEntryVisitedEvent<String, String> event) {
+        this.printLog("Key '" + event.getKey() + "' was visited", event);
+    }
+
+    @CacheEntryActivated
+    public void entryActivated(CacheEntryActivatedEvent<String, String> event) {
+        this.printLog("Activating key '" + event.getKey() + "' on cache", event);
+    }
+
+    @CacheEntryPassivated
+    public void entryPassivated(CacheEntryPassivatedEvent<String, String> event) {
+        this.printLog("Passivating key '" + event.getKey() + "' from cache", event);
+    }
+
+    @CacheEntryLoaded
+    public void entryLoaded(CacheEntryLoadedEvent<String, String> event) {
+        this.printLog("Loading key '" + event.getKey() + "' to cache", event);
+    }
+
+    @CacheEntriesEvicted
+    public void entriesEvicted(CacheEntriesEvictedEvent<String, String> event) {
+        final StringBuilder builder = new StringBuilder();
+        event.getEntries().forEach((key, value) -> builder.append(key).append(", "));
+        System.out.println("Evicting following entries from cache: " + builder.toString());
+    }
+
+    private void printLog(String log, CacheEntryEvent event) {
+        if (!event.isPre()) {
+            System.out.println(log);
+        }
+    }
+
+}
diff --git a/libraries/src/main/java/com/baeldung/infinispan/repository/HelloWorldRepository.java b/libraries/src/main/java/com/baeldung/infinispan/repository/HelloWorldRepository.java
new file mode 100644
index 0000000000..85c0d539a3
--- /dev/null
+++ b/libraries/src/main/java/com/baeldung/infinispan/repository/HelloWorldRepository.java
@@ -0,0 +1,15 @@
+package com.baeldung.infinispan.repository;
+
+public class HelloWorldRepository {
+
+    public String getHelloWorld() {
+        try {
+            System.out.println("Executing some heavy query");
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        return "Hello World!";
+    }
+
+}
diff --git a/libraries/src/main/java/com/baeldung/infinispan/service/HelloWorldService.java b/libraries/src/main/java/com/baeldung/infinispan/service/HelloWorldService.java
new file mode 100644
index 0000000000..3ecefcc21a
--- /dev/null
+++ b/libraries/src/main/java/com/baeldung/infinispan/service/HelloWorldService.java
@@ -0,0 +1,80 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import com.baeldung.infinispan.repository.HelloWorldRepository;
+import org.infinispan.Cache;
+
+import java.util.concurrent.TimeUnit;
+
+public class HelloWorldService {
+
+    private final HelloWorldRepository repository;
+
+    private final Cache<String, String> simpleHelloWorldCache;
+    private final Cache<String, String> expiringHelloWorldCache;
+    private final Cache<String, String> evictingHelloWorldCache;
+    private final Cache<String, String> passivatingHelloWorldCache;
+
+    public HelloWorldService(HelloWorldRepository repository, CacheListener listener,
+      Cache<String, String> simpleHelloWorldCache,
+      Cache<String, String> expiringHelloWorldCache,
+      Cache<String, String> evictingHelloWorldCache,
+      Cache<String, String> passivatingHelloWorldCache) {
+
+        this.repository = repository;
+
+        this.simpleHelloWorldCache = simpleHelloWorldCache;
+        this.expiringHelloWorldCache = expiringHelloWorldCache;
+        this.evictingHelloWorldCache = evictingHelloWorldCache;
+        this.passivatingHelloWorldCache = passivatingHelloWorldCache;
+    }
+
+    public String findSimpleHelloWorld() {
+        String cacheKey = "simple-hello";
+        return simpleHelloWorldCache.computeIfAbsent(cacheKey, k -> repository.getHelloWorld());
+    }
+
+    public String findExpiringHelloWorld() {
+        String cacheKey = "expiring-hello";
+        String helloWorld = simpleHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            simpleHelloWorldCache.put(cacheKey, helloWorld, 1, TimeUnit.SECONDS);
+        }
+        return helloWorld;
+    }
+
+    public String findIdleHelloWorld() {
+        String cacheKey = "idle-hello";
+        String helloWorld = simpleHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            simpleHelloWorldCache.put(cacheKey, helloWorld, -1, TimeUnit.SECONDS, 10, TimeUnit.SECONDS);
+        }
+        return helloWorld;
+    }
+
+    public String findSimpleHelloWorldInExpiringCache() {
+        String cacheKey = "simple-hello";
+        String helloWorld = expiringHelloWorldCache.get(cacheKey);
+        if (helloWorld == null) {
+            helloWorld = repository.getHelloWorld();
+            expiringHelloWorldCache.put(cacheKey, helloWorld);
+        }
+        return helloWorld;
+    }
+
+    public String findEvictingHelloWorld(String key) {
+        String value = evictingHelloWorldCache.get(key);
+        if(value == null) {
+            value = repository.getHelloWorld();
+            evictingHelloWorldCache.put(key, value);
+        }
+        return value;
+    }
+
+    public String findPassivatingHelloWorld(String key) {
+        return passivatingHelloWorldCache.computeIfAbsent(key, k -> repository.getHelloWorld());
+    }
+
+}
diff --git a/libraries/src/main/java/com/baeldung/infinispan/service/TransactionalService.java b/libraries/src/main/java/com/baeldung/infinispan/service/TransactionalService.java
new file mode 100644
index 0000000000..b0dbf5475f
--- /dev/null
+++ b/libraries/src/main/java/com/baeldung/infinispan/service/TransactionalService.java
@@ -0,0 +1,57 @@
+package com.baeldung.infinispan.service;
+
+import org.infinispan.Cache;
+import org.springframework.util.StopWatch;
+
+import javax.transaction.TransactionManager;
+
+public class TransactionalService {
+
+    private final Cache<String, Integer> transactionalCache;
+
+    private static final String KEY = "key";
+
+    public TransactionalService(Cache<String, Integer> transactionalCache) {
+        this.transactionalCache = transactionalCache;
+
+        transactionalCache.put(KEY, 0);
+    }
+
+    public Integer getQuickHowManyVisits() {
+        try {
+            TransactionManager tm = transactionalCache.getAdvancedCache().getTransactionManager();
+            tm.begin();
+            Integer howManyVisits = transactionalCache.get(KEY);
+            howManyVisits++;
+            System.out.println("Ill try to set HowManyVisits to " + howManyVisits);
+            StopWatch watch = new StopWatch();
+            watch.start();
+            transactionalCache.put(KEY, howManyVisits);
+            watch.stop();
+            System.out.println("I was able to set HowManyVisits to " + howManyVisits +
+              " after waiting " + watch.getTotalTimeSeconds() + " seconds");
+
+            tm.commit();
+            return howManyVisits;
+        } catch (Exception e) {
+            e.printStackTrace();
+            return 0;
+        }
+    }
+
+    public void startBackgroundBatch() {
+        try {
+            TransactionManager tm = transactionalCache.getAdvancedCache().getTransactionManager();
+            tm.begin();
+            transactionalCache.put(KEY, 1000);
+            System.out.println("HowManyVisits should now be 1000, " +
+              "but we are holding the transaction");
+            Thread.sleep(1000L);
+            tm.rollback();
+            System.out.println("The slow batch suffered a rollback");
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+}
diff --git a/libraries/src/main/resources/Greeting.sol b/libraries/src/main/resources/Greeting.sol
new file mode 100644
index 0000000000..dde7b36cc3
--- /dev/null
+++ b/libraries/src/main/resources/Greeting.sol
@@ -0,0 +1,19 @@
+pragma solidity ^0.4.0;
+
+contract Greeting {
+    address creator;
+    string message;
+
+    function Greeting(string _message) {
+        message = _message;
+        creator = msg.sender;
+    }
+
+    function greet() constant returns (string) {
+        return message;
+    }
+
+    function setGreeting(string _message) {
+        message = _message;
+    }
+}
\ No newline at end of file
diff --git a/libraries/src/test/java/com/baeldung/infinispan/ConfigurationTest.java b/libraries/src/test/java/com/baeldung/infinispan/ConfigurationTest.java
new file mode 100644
index 0000000000..c9ebe77679
--- /dev/null
+++ b/libraries/src/test/java/com/baeldung/infinispan/ConfigurationTest.java
@@ -0,0 +1,62 @@
+package com.baeldung.infinispan;
+
+import com.baeldung.infinispan.listener.CacheListener;
+import com.baeldung.infinispan.repository.HelloWorldRepository;
+import com.baeldung.infinispan.service.HelloWorldService;
+import com.baeldung.infinispan.service.TransactionalService;
+import org.infinispan.Cache;
+import org.infinispan.manager.DefaultCacheManager;
+import org.junit.After;
+import org.junit.Before;
+
+import java.util.function.Supplier;
+
+public class ConfigurationTest {
+
+    private DefaultCacheManager cacheManager;
+
+    private HelloWorldRepository repository = new HelloWorldRepository();
+
+    protected HelloWorldService helloWorldService;
+    protected TransactionalService transactionalService;
+
+    @Before
+    public void setup() {
+        CacheConfiguration configuration = new CacheConfiguration();
+        CacheListener listener = new CacheListener();
+
+        cacheManager = configuration.cacheManager();
+
+        Cache<String, Integer> transactionalCache =
+          configuration.transactionalCache(cacheManager, listener);
+
+        Cache<String, String> simpleHelloWorldCache =
+          configuration.simpleHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> expiringHelloWorldCache =
+          configuration.expiringHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> evictingHelloWorldCache =
+          configuration.evictingHelloWorldCache(cacheManager, listener);
+
+        Cache<String, String> passivatingHelloWorldCache =
+          configuration.passivatingHelloWorldCache(cacheManager, listener);
+
+        this.helloWorldService = new HelloWorldService(repository,
+          listener, simpleHelloWorldCache, expiringHelloWorldCache, evictingHelloWorldCache,
+          passivatingHelloWorldCache);
+
+        this.transactionalService = new TransactionalService(transactionalCache);
+    }
+
+    @After
+    public void tearDown() {
+        cacheManager.stop();
+    }
+
+    protected <T> long timeThis(Supplier<T> supplier) {
+        long millis = System.currentTimeMillis();
+        supplier.get();
+        return System.currentTimeMillis() - millis;
+    }
+}
diff --git a/libraries/src/test/java/com/baeldung/infinispan/service/HelloWorldServiceUnitTest.java b/libraries/src/test/java/com/baeldung/infinispan/service/HelloWorldServiceUnitTest.java
new file mode 100644
index 0000000000..c9ecd57995
--- /dev/null
+++ b/libraries/src/test/java/com/baeldung/infinispan/service/HelloWorldServiceUnitTest.java
@@ -0,0 +1,71 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.ConfigurationTest;
+import org.junit.Test;
+
+import java.util.concurrent.Callable;
+import java.util.function.Consumer;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class HelloWorldServiceUnitTest extends ConfigurationTest {
+
+    @Test
+    public void whenGetIsCalledTwoTimes_thenTheSecondShouldHitTheCache() {
+        assertThat(timeThis(() -> helloWorldService.findSimpleHelloWorld()))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findSimpleHelloWorld()))
+          .isLessThan(100);
+    }
+
+    @Test
+    public void whenGetIsCalledTwoTimesQuickly_thenTheSecondShouldHitTheCache() {
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld()))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld()))
+          .isLessThan(100);
+    }
+
+    @Test
+    public void whenGetIsCalledTwoTimesSparsely_thenNeitherShouldHitTheCache()
+            throws InterruptedException {
+
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld()))
+          .isGreaterThanOrEqualTo(1000);
+
+        Thread.sleep(1100);
+
+        assertThat(timeThis(() -> helloWorldService.findExpiringHelloWorld()))
+          .isGreaterThanOrEqualTo(1000);
+    }
+
+    @Test
+    public void givenOneEntryIsConfigured_whenTwoAreAdded_thenFirstShouldntBeAvailable() {
+
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 1")))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 2")))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findEvictingHelloWorld("key 1")))
+          .isGreaterThanOrEqualTo(1000);
+    }
+
+    @Test
+    public void givenOneEntryIsConfigured_whenTwoAreAdded_thenTheFirstShouldBeAvailable() {
+
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 1")))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 2")))
+          .isGreaterThanOrEqualTo(1000);
+
+        assertThat(timeThis(() -> helloWorldService.findPassivatingHelloWorld("key 1")))
+          .isLessThan(100);
+
+    }
+
+}
diff --git a/libraries/src/test/java/com/baeldung/infinispan/service/TransactionalServiceUnitTest.java b/libraries/src/test/java/com/baeldung/infinispan/service/TransactionalServiceUnitTest.java
new file mode 100644
index 0000000000..99efacd18a
--- /dev/null
+++ b/libraries/src/test/java/com/baeldung/infinispan/service/TransactionalServiceUnitTest.java
@@ -0,0 +1,22 @@
+package com.baeldung.infinispan.service;
+
+import com.baeldung.infinispan.ConfigurationTest;
+import org.junit.Test;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class TransactionalServiceUnitTest extends ConfigurationTest {
+
+    @Test
+    public void whenLockingAnEntry_thenItShouldBeInaccessible() throws InterruptedException {
+        Runnable backGroundJob = () -> transactionalService.startBackgroundBatch();
+        Thread backgroundThread = new Thread(backGroundJob);
+        transactionalService.getQuickHowManyVisits();
+        backgroundThread.start();
+        Thread.sleep(100); //lets wait our thread warm up
+
+        assertThat(timeThis(() -> transactionalService.getQuickHowManyVisits()))
+          .isGreaterThan(500).isLessThan(1000);
+    }
+
+}
diff --git a/logging-modules/log4j/src/main/resources/logback.xml b/logging-modules/log4j/src/main/resources/logback.xml
index f567962cb6..097f6694f0 100644
--- a/logging-modules/log4j/src/main/resources/logback.xml
+++ b/logging-modules/log4j/src/main/resources/logback.xml
@@ -78,7 +78,7 @@
         <appender-ref ref="roll-by-time-and-size"/>
     </logger>
 
-    <root level="DEBUG">
+    <root level="INFO">
         <appender-ref ref="stdout"/>
         <appender-ref ref="fout"/>
     </root>
diff --git a/microprofile/pom.xml b/microprofile/pom.xml
new file mode 100644
index 0000000000..ce8a2d13ca
--- /dev/null
+++ b/microprofile/pom.xml
@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.baeldung</groupId>
+    <artifactId>microprofile</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <packaging>war</packaging>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+        <app.name>library</app.name>
+        <package.file>${project.build.directory}/${app.name}-service.jar</package.file>
+        <packaging.type>runnable</packaging.type>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.eclipse.microprofile</groupId>
+            <artifactId>microprofile</artifactId>
+            <version>1.2</version>
+            <scope>provided</scope>
+            <type>pom</type>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <artifactId>maven-war-plugin</artifactId>
+                <configuration>
+                    <failOnMissingWebXml>false</failOnMissingWebXml>
+                    <packagingExcludes>pom.xml</packagingExcludes>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>net.wasdev.wlp.maven.plugins</groupId>
+                <artifactId>liberty-maven-plugin</artifactId>
+                <version>2.1.2</version>
+                <configuration>
+                    <assemblyArtifact>
+                        <groupId>io.openliberty</groupId>
+                        <artifactId>openliberty-runtime</artifactId>
+                        <version>17.0.0.4</version>
+                        <type>zip</type>
+                    </assemblyArtifact>
+                    <configFile>${basedir}/src/main/liberty/config/server.xml</configFile>
+                    <packageFile>${package.file}</packageFile>
+                    <include>${packaging.type}</include>
+                    <looseApplication>false</looseApplication>
+                    <installAppPackages>project</installAppPackages>
+                    <bootstrapProperties>
+                        <app.context.root>/</app.context.root>
+                        <app.location>${project.artifactId}-${project.version}.war</app.location>
+                        <default.http.port>9080</default.http.port>
+                        <default.https.port>9443</default.https.port>
+                    </bootstrapProperties>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>install-server</id>
+                        <phase>prepare-package</phase>
+                        <goals>
+                            <goal>install-server</goal>
+                            <goal>create-server</goal>
+                            <goal>install-feature</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                        <id>package-server-with-apps</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>install-apps</goal>
+                            <goal>package-server</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/LibraryApplication.java b/microprofile/src/main/java/com/baeldung/microprofile/LibraryApplication.java
new file mode 100644
index 0000000000..f5eccf969e
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/LibraryApplication.java
@@ -0,0 +1,8 @@
+package com.baeldung.microprofile;
+
+import javax.ws.rs.ApplicationPath;
+import javax.ws.rs.core.Application;
+
+@ApplicationPath("/library")
+public class LibraryApplication extends Application {
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/model/Book.java b/microprofile/src/main/java/com/baeldung/microprofile/model/Book.java
new file mode 100644
index 0000000000..44b7f5428d
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/model/Book.java
@@ -0,0 +1,50 @@
+package com.baeldung.microprofile.model;
+
+public class Book {
+
+    private String id;
+    private String isbn;
+    private String name;
+    private String author;
+    private Integer pages;
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getIsbn() {
+        return isbn;
+    }
+
+    public void setIsbn(String isbn) {
+        this.isbn = isbn;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public Integer getPages() {
+        return pages;
+    }
+
+    public void setPages(Integer pages) {
+        this.pages = pages;
+    }
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/providers/BookListMessageBodyWriter.java b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookListMessageBodyWriter.java
new file mode 100644
index 0000000000..f7d0bfc5f7
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookListMessageBodyWriter.java
@@ -0,0 +1,42 @@
+package com.baeldung.microprofile.providers;
+
+import com.baeldung.microprofile.model.Book;
+import com.baeldung.microprofile.util.BookMapper;
+
+import javax.json.Json;
+import javax.json.JsonArray;
+import javax.json.JsonWriter;
+import javax.ws.rs.Produces;
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.MessageBodyWriter;
+import javax.ws.rs.ext.Provider;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Type;
+import java.util.List;
+
+@Provider
+@Produces(MediaType.APPLICATION_JSON)
+public class BookListMessageBodyWriter implements MessageBodyWriter<List<Book>> {
+
+    @Override
+    public boolean isWriteable(Class<?> clazz, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return true;
+    }
+
+    @Override
+    public long getSize(List<Book> books, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return 0;
+    }
+
+    @Override
+    public void writeTo(List<Book> books, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException, WebApplicationException {
+        JsonWriter jsonWriter = Json.createWriter(entityStream);
+        JsonArray jsonArray = BookMapper.map(books);
+        jsonWriter.writeArray(jsonArray);
+        jsonWriter.close();
+    }
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyReader.java b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyReader.java
new file mode 100644
index 0000000000..26ce4c1b64
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyReader.java
@@ -0,0 +1,30 @@
+package com.baeldung.microprofile.providers;
+
+import com.baeldung.microprofile.model.Book;
+import com.baeldung.microprofile.util.BookMapper;
+
+import javax.ws.rs.Consumes;
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.MessageBodyReader;
+import javax.ws.rs.ext.Provider;
+import java.io.IOException;
+import java.io.InputStream;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Type;
+
+@Provider
+@Consumes(MediaType.APPLICATION_JSON)
+public class BookMessageBodyReader implements MessageBodyReader<Book> {
+
+    @Override
+    public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return type.equals(Book.class);
+    }
+
+    @Override
+    public Book readFrom(Class<Book> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, String> httpHeaders, InputStream entityStream) throws IOException, WebApplicationException {
+        return BookMapper.map(entityStream);
+    }
+}
\ No newline at end of file
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyWriter.java b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyWriter.java
new file mode 100644
index 0000000000..9bc6e89958
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/providers/BookMessageBodyWriter.java
@@ -0,0 +1,57 @@
+package com.baeldung.microprofile.providers;
+
+import com.baeldung.microprofile.model.Book;
+import com.baeldung.microprofile.util.BookMapper;
+
+import javax.json.Json;
+import javax.json.JsonObject;
+import javax.json.JsonWriter;
+import javax.ws.rs.Produces;
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.MessageBodyWriter;
+import javax.ws.rs.ext.Provider;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Type;
+
+@Provider
+@Produces(MediaType.APPLICATION_JSON)
+public class BookMessageBodyWriter implements MessageBodyWriter<Book> {
+    @Override
+    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return type.equals(Book.class);
+    }
+
+    /*
+    Deprecated in JAX RS 2.0
+     */
+    @Override
+    public long getSize(Book book, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
+        return 0;
+    }
+
+    /**
+     * Marsahl Book to OutputStream
+     *
+     * @param book
+     * @param type
+     * @param genericType
+     * @param annotations
+     * @param mediaType
+     * @param httpHeaders
+     * @param entityStream
+     * @throws IOException
+     * @throws WebApplicationException
+     */
+    @Override
+    public void writeTo(Book book, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException, WebApplicationException {
+        JsonWriter jsonWriter = Json.createWriter(entityStream);
+        JsonObject jsonObject = BookMapper.map(book);
+        jsonWriter.writeObject(jsonObject);
+        jsonWriter.close();
+    }
+
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/repo/BookManager.java b/microprofile/src/main/java/com/baeldung/microprofile/repo/BookManager.java
new file mode 100644
index 0000000000..924cf0ce71
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/repo/BookManager.java
@@ -0,0 +1,53 @@
+package com.baeldung.microprofile.repo;
+
+import com.baeldung.microprofile.model.Book;
+
+import javax.enterprise.context.ApplicationScoped;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
+@ApplicationScoped
+public class BookManager {
+
+    private DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMM");
+    private AtomicInteger bookIdGenerator = new AtomicInteger(0);
+
+    private ConcurrentMap<String, Book> inMemoryStore = new ConcurrentHashMap<>();
+
+    public BookManager() {
+        Book book = new Book();
+        book.setId(getNextId());
+        book.setName("Building Microservice With Eclipse MicroProfile");
+        book.setIsbn("1");
+        book.setAuthor("baeldung");
+        book.setPages(420);
+        inMemoryStore.put(book.getId(), book);
+    }
+
+    private String getNextId() {
+        String date = LocalDate.now().format(formatter);
+        return String.format("%04d-%s", bookIdGenerator.incrementAndGet(), date);
+    }
+
+    public String add(Book book) {
+        String id = getNextId();
+        book.setId(id);
+        inMemoryStore.put(id, book);
+        return id;
+    }
+
+    public Book get(String id) {
+        return inMemoryStore.get(id);
+    }
+
+    public List<Book> getAll() {
+        List<Book> books = new ArrayList<>();
+        books.addAll(inMemoryStore.values());
+        return books;
+    }
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/util/BookMapper.java b/microprofile/src/main/java/com/baeldung/microprofile/util/BookMapper.java
new file mode 100644
index 0000000000..861b172299
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/util/BookMapper.java
@@ -0,0 +1,72 @@
+package com.baeldung.microprofile.util;
+
+import com.baeldung.microprofile.model.Book;
+
+import javax.json.*;
+import java.io.InputStream;
+import java.util.List;
+
+public class BookMapper {
+
+    public static JsonObject map(Book book) {
+        JsonObjectBuilder builder = Json.createObjectBuilder();
+        addValue(builder, "id", book.getId());
+        addValue(builder, "isbn", book.getIsbn());
+        addValue(builder, "name", book.getName());
+        addValue(builder, "author", book.getAuthor());
+        addValue(builder, "pages", book.getPages());
+        return builder.build();
+    }
+
+    private static void addValue(JsonObjectBuilder builder, String key, Object value) {
+        if (value != null) {
+            builder.add(key, value.toString());
+        } else {
+            builder.addNull(key);
+        }
+    }
+
+    public static JsonArray map(List<Book> books) {
+        final JsonArrayBuilder arrayBuilder = Json.createArrayBuilder();
+        books.forEach(book -> {
+            JsonObject jsonObject = map(book);
+            arrayBuilder.add(jsonObject);
+        });
+        return arrayBuilder.build();
+    }
+
+    public static Book map(InputStream is) {
+        try(JsonReader jsonReader = Json.createReader(is)) {
+            JsonObject jsonObject = jsonReader.readObject();
+            Book book = new Book();
+            book.setId(getStringFromJson("id", jsonObject));
+            book.setIsbn(getStringFromJson("isbn", jsonObject));
+            book.setName(getStringFromJson("name", jsonObject));
+            book.setAuthor(getStringFromJson("author", jsonObject));
+            book.setPages(getIntFromJson("pages",jsonObject));
+            return book;
+        }
+    }
+
+    private static String getStringFromJson(String key, JsonObject json) {
+        String returnedString = null;
+        if (json.containsKey(key)) {
+            JsonString value = json.getJsonString(key);
+            if (value != null) {
+                returnedString = value.getString();
+            }
+        }
+        return returnedString;
+    }
+
+    private static Integer getIntFromJson(String key, JsonObject json) {
+        Integer returnedValue = null;
+        if (json.containsKey(key)) {
+            JsonNumber value = json.getJsonNumber(key);
+            if (value != null) {
+                returnedValue = value.intValue();
+            }
+        }
+        return returnedValue;
+    }
+}
diff --git a/microprofile/src/main/java/com/baeldung/microprofile/web/BookEndpoint.java b/microprofile/src/main/java/com/baeldung/microprofile/web/BookEndpoint.java
new file mode 100644
index 0000000000..13143a5644
--- /dev/null
+++ b/microprofile/src/main/java/com/baeldung/microprofile/web/BookEndpoint.java
@@ -0,0 +1,42 @@
+package com.baeldung.microprofile.web;
+
+import com.baeldung.microprofile.model.Book;
+import com.baeldung.microprofile.repo.BookManager;
+
+import javax.enterprise.context.RequestScoped;
+import javax.inject.Inject;
+import javax.ws.rs.*;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.core.UriBuilder;
+
+@Path("books")
+@RequestScoped
+public class BookEndpoint {
+
+    @Inject
+    private BookManager bookManager;
+
+    @GET
+    @Path("{id}")
+    @Produces(MediaType.APPLICATION_JSON)
+    public Response getBook(@PathParam("id") String id) {
+        Book book = bookManager.get(id);
+        return Response.ok(book).build();
+    }
+
+    @GET
+    @Produces(MediaType.APPLICATION_JSON)
+    public Response getAllBooks() {
+        return Response.ok(bookManager.getAll()).build();
+    }
+
+    @POST
+    @Consumes(MediaType.APPLICATION_JSON)
+    public Response add(Book book) {
+        String bookId = bookManager.add(book);
+        return Response.created(
+                UriBuilder.fromResource(this.getClass()).path(bookId).build())
+                .build();
+    }
+}
diff --git a/microprofile/src/main/liberty/config/server.xml b/microprofile/src/main/liberty/config/server.xml
new file mode 100644
index 0000000000..2b855bee05
--- /dev/null
+++ b/microprofile/src/main/liberty/config/server.xml
@@ -0,0 +1,11 @@
+<server description="OpenLiberty MicroProfile server">
+    <featureManager>
+        <feature>jaxrs-2.0</feature>
+        <feature>cdi-1.2</feature>
+        <feature>jsonp-1.0</feature>
+    </featureManager>
+    <httpEndpoint httpPort="${default.http.port}" httpsPort="${default.https.port}"
+                  id="defaultHttpEndpoint" host="*"/>
+    <applicationManager autoExpand="true"/>
+    <webApplication context-root="${app.context.root}" location="${app.location}"/>
+</server>
diff --git a/out/production/generated-sources8/src.main.resources.reladomo.ReladomoClassList.xml.log b/out/production/generated-sources8/src.main.resources.reladomo.ReladomoClassList.xml.log
new file mode 100644
index 0000000000..0bd4e29a45
--- /dev/null
+++ b/out/production/generated-sources8/src.main.resources.reladomo.ReladomoClassList.xml.log
@@ -0,0 +1,2 @@
+f5a6ba3b942a82fcbfb72e61502d5c30
+9201deea
diff --git a/out/production/introduction/views/index.scala.html b/out/production/introduction/views/index.scala.html
new file mode 100644
index 0000000000..4539f5a10b
--- /dev/null
+++ b/out/production/introduction/views/index.scala.html
@@ -0,0 +1,20 @@
+@*
+ * This template takes a single argument, a String containing a
+ * message to display.
+ *@
+@(message: String)
+
+@*
+ * Call the `main` template with two arguments. The first
+ * argument is a `String` with the title of the page, the second
+ * argument is an `Html` object containing the body of the page.
+ *@
+@main("Welcome to Play") {
+
+    @*
+     * Get an `Html` object by calling the built-in Play welcome
+     * template and passing a `String` message.
+     *@
+    @play20.welcome(message, style = "Java")
+
+}
diff --git a/out/production/introduction/views/main.scala.html b/out/production/introduction/views/main.scala.html
new file mode 100644
index 0000000000..9414f4be6e
--- /dev/null
+++ b/out/production/introduction/views/main.scala.html
@@ -0,0 +1,23 @@
+@*
+ * This template is called from the `index` template. This template
+ * handles the rendering of the page header and body tags. It takes
+ * two arguments, a `String` for the title of the page and an `Html`
+ * object to insert into the body of the page.
+ *@
+@(title: String)(content: Html)
+
+<!DOCTYPE html>
+<html lang="en">
+    <head>
+        @* Here's where we render the page title `String`. *@
+        <title>@title</title>
+        <link rel="stylesheet" media="screen" href="@routes.Assets.versioned("stylesheets/main.css")">
+        <link rel="shortcut icon" type="image/png" href="@routes.Assets.versioned("images/favicon.png")">
+        <script src="@routes.Assets.versioned("javascripts/hello.js")" type="text/javascript"></script>
+    </head>
+    <body>
+        @* And here's where we render the `Html` object containing
+         * the page content. *@
+        @content
+    </body>
+</html>
diff --git a/out/production/main122/.gitignore b/out/production/main122/.gitignore
new file mode 100644
index 0000000000..83c05e60c8
--- /dev/null
+++ b/out/production/main122/.gitignore
@@ -0,0 +1,13 @@
+*.class
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+
+# Packaged files #
+*.jar
+*.war
+*.ear
\ No newline at end of file
diff --git a/out/production/main151/com/baeldung/.gitignore b/out/production/main151/com/baeldung/.gitignore
new file mode 100644
index 0000000000..83c05e60c8
--- /dev/null
+++ b/out/production/main151/com/baeldung/.gitignore
@@ -0,0 +1,13 @@
+*.class
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+
+# Packaged files #
+*.jar
+*.war
+*.ear
\ No newline at end of file
diff --git a/out/production/main151/com/baeldung/README.md b/out/production/main151/com/baeldung/README.md
new file mode 100644
index 0000000000..51809b2882
--- /dev/null
+++ b/out/production/main151/com/baeldung/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [SHA-256 Hashing in Java](http://www.baeldung.com/sha-256-hashing-java)
diff --git a/out/production/main155/com/baeldung/git/README.md b/out/production/main155/com/baeldung/git/README.md
new file mode 100644
index 0000000000..7e6a597c28
--- /dev/null
+++ b/out/production/main155/com/baeldung/git/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Injecting Git Information Into Spring](http://www.baeldung.com/spring-git-information)
diff --git a/out/production/main173/log4j.properties b/out/production/main173/log4j.properties
new file mode 100644
index 0000000000..5fe42d854c
--- /dev/null
+++ b/out/production/main173/log4j.properties
@@ -0,0 +1,9 @@
+# Set root logger level to DEBUG and its only appender to A1.
+log4j.rootLogger=DEBUG, A1
+
+# A1 is set to be a ConsoleAppender.
+log4j.appender.A1=org.apache.log4j.ConsoleAppender
+
+# A1 uses PatternLayout.
+log4j.appender.A1.layout=org.apache.log4j.PatternLayout
+log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/README.txt b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/README.txt
new file mode 100644
index 0000000000..bffe24e485
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/README.txt
@@ -0,0 +1,76 @@
+About the application
+---------------------
+This application demonstrates the usage of JavaEE Web Annotations.
+
+
+Contents of the application
+---------------------------
+1. AccountServlet.java - Demonstrates the @WebServlet and @ServletSecurity annotation.
+
+NOTES: @WebServlet annotation designates the AccountServlet class as a Servlet component.
+       The usage of its parameters 'urlPatterns' & 'initParams' can be observed.
+       An initialization parameter 'type' is being set to denote the type of the bank account.
+       
+       @ServletSecurity annotation imposes security constraints on the AccountServlet based on
+       the tomcat-users.xml.
+       
+       This code assumes that your tomcat-users.xml looks as follows:
+
+       <role rolename="Admin"/>
+       <role rolename="Member"/>
+       <role rolename="Guest"/>
+       <user username="Annie" password="admin" roles="Admin, Member, Guest" />
+       <user username="Diane" password="coder" roles="Member, Guest" />
+       <user username="Ted" password="newbie" roles="Guest" />
+   
+N.B : To see  @ServletSecurity annotation in action, please uncomment the annotation code 
+      for @ServletSecurity.
+      
+      
+2. BankAppServletContextListener.java - Demonstrates the @WebListener annotation for denoting a class as a ServletContextListener.
+   
+NOTES: Sets a Servlet context attribute ATTR_DEFAULT_LANGUAGE to 'english' on web application start up, 
+       which can then be used throughout the application.
+
+
+3. LogInFilter.java - Demonstrates the @WebFilter annotation.
+                      
+NOTES: @WebFilter annotation designates the LogInFilter class as a Filter component.
+       It filters all requests to the bank account servlet and redirects them to
+       the login page.
+       
+N.B : To see @WebFilter annotation in action, please uncomment the annotation code for @WebFilter.
+
+
+4. UploadCustomerDocumentsServlet.java - Demonstrates the @MultipartConfig annotation.
+
+NOTES: @MultipartConfig anotation designates the UploadCustomerDocumentsServlet Servlet component, 
+       to handle multipart/form-data requests.
+       To see it in action, deploy the web application an access the url: http://<your host>:<your port>/JavaEEAnnotationsSample/upload.jsp
+       Once you upload a file from here, it will get uploaded to D:/custDocs (assuming such a folder exists).
+       
+ 
+5. index.jsp - This is the welcome page.
+
+NOTES: You can enter a deposit amount here and click on the 'Deposit' button to see the AccountServlet in action.
+
+6. login.jsp - All requests to the AccountServlet are redirected to this page, if the LogInFilter is imposed.
+
+7. upload.jsp - Demonstrates the usage of handling multipart/form-data requests by the UploadCustomerDocumentsServlet.       
+       
+   
+Building and Running the application
+------------------------------------
+To build the application:
+
+1. Open the project in eclipse
+2. Right click on it in eclispe and choose Run As > Maven build
+3. Give 'clean install' under Goals
+4. This should build the WAR file of the application
+
+To run the application:
+
+1. Right click on the project
+2. Run as > Run on Server
+3. This will start you Tomcat server and deploy the application (Provided that you have configured Tomcat in your eclipse)
+4. You should now be able to access the url : http://<your host>:<your port>/JavaEEAnnotationsSample
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/pom.xml b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/pom.xml
new file mode 100644
index 0000000000..de69efa43a
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/pom.xml
@@ -0,0 +1,57 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>com.baeldung.javaeeannotations</groupId>
+  <artifactId>JavaEEAnnotationsSample</artifactId>
+  <version>0.0.1-SNAPSHOT</version>
+  <packaging>war</packaging>
+  <name>JavaEEAnnotationsSample</name>
+  <description>JavaEEAnnotationsSample</description>
+  
+  <dependencies>
+		
+	<dependency>
+	    <groupId>javax.annotation</groupId>
+	    <artifactId>javax.annotation-api</artifactId>
+	    <version>1.3</version>
+	</dependency>
+	
+	<dependency>
+	    <groupId>javax.servlet</groupId>
+	    <artifactId>javax.servlet-api</artifactId>
+	    <version>3.1.0</version>
+	</dependency>
+	
+	<dependency>
+	    <groupId>javax.servlet.jsp</groupId>
+	    <artifactId>jsp-api</artifactId>
+	    <version>2.1</version>
+	</dependency>
+		
+	</dependencies>
+	<build>
+		<pluginManagement>
+			<plugins>
+				<plugin>
+					<groupId>org.apache.maven.plugins</groupId>
+					<artifactId>maven-compiler-plugin</artifactId>
+					<version>3.7.0</version>
+					<configuration>
+						<source>1.8</source>
+						<target>1.8</target>
+					</configuration>
+				</plugin>
+				<plugin>
+					<groupId>org.apache.maven.plugins</groupId>
+					<artifactId>maven-war-plugin</artifactId>
+					<version>2.4</version>
+					<configuration>
+						<warSourceDirectory>src/main/webapp</warSourceDirectory>
+						<warName>SpringFieldConstructorInjection</warName>
+						<failOnMissingWebXml>false</failOnMissingWebXml>
+					</configuration>
+				</plugin>
+			</plugins>
+		</pluginManagement>
+		<finalName>JavaEEAnnotationsSample</finalName>
+	</build>
+</project>
\ No newline at end of file
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/WEB-INF/web.xml b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/WEB-INF/web.xml
new file mode 100644
index 0000000000..a92885ec11
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/WEB-INF/web.xml
@@ -0,0 +1,10 @@
+<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
+                             http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
+
+    <login-config>
+        <auth-method>BASIC</auth-method>
+        <realm-name>default</realm-name>
+    </login-config>
+</web-app>
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/index.jsp b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/index.jsp
new file mode 100644
index 0000000000..c49dec859e
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/index.jsp
@@ -0,0 +1,16 @@
+<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
+    pageEncoding="ISO-8859-1"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>My Account</title>
+</head>
+<body>
+<form action="bankAccount" method="post">
+        Amount: <input type="text" size="5" name="dep"/> 
+        &nbsp;&nbsp;
+        <input type="submit" value="Deposit" />
+</form>
+</body>
+</html>
\ No newline at end of file
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/login.jsp b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/login.jsp
new file mode 100644
index 0000000000..6892cb0420
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/login.jsp
@@ -0,0 +1,12 @@
+<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
+    pageEncoding="ISO-8859-1"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>Login</title>
+</head>
+<body>
+Login Here...
+</body>
+</html>
\ No newline at end of file
diff --git a/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/upload.jsp b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/upload.jsp
new file mode 100644
index 0000000000..3601322ef0
--- /dev/null
+++ b/out/production/main180/com/baeldung/javaeeannotations/JavaEEAnnotationsSample/src/main/webapp/upload.jsp
@@ -0,0 +1,16 @@
+<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
+    pageEncoding="ISO-8859-1"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>Insert title here</title>
+</head>
+<body>
+<form action="uploadCustDocs" method="post" enctype="multipart/form-data">
+<input type="file" name="file" size="50" />
+<br />
+<input type="submit" value="Upload File" />
+</form>
+</body>
+</html>
\ No newline at end of file
diff --git a/out/production/main180/com/baeldung/jaxws/wsdl/employeeservicetopdown.wsdl b/out/production/main180/com/baeldung/jaxws/wsdl/employeeservicetopdown.wsdl
new file mode 100644
index 0000000000..426717f90e
--- /dev/null
+++ b/out/production/main180/com/baeldung/jaxws/wsdl/employeeservicetopdown.wsdl
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<definitions xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
+             xmlns:tns="http://topdown.server.jaxws.baeldung.com/"
+             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+             xmlns="http://schemas.xmlsoap.org/wsdl/"
+             targetNamespace="http://topdown.server.jaxws.baeldung.com/"
+             name="EmployeeServiceTopDown">
+    <types>
+        <xsd:schema targetNamespace="http://topdown.server.jaxws.baeldung.com/">
+            <xsd:element name="countEmployeesResponse" type="xsd:int"/>
+        </xsd:schema>
+    </types>
+
+    <message name="countEmployees">
+    </message>
+    <message name="countEmployeesResponse">
+        <part name="parameters" element="tns:countEmployeesResponse"/>
+    </message>
+    <portType name="EmployeeServiceTopDown">
+        <operation name="countEmployees">
+            <input message="tns:countEmployees"/>
+            <output message="tns:countEmployeesResponse"/>
+        </operation>
+    </portType>
+    <binding name="EmployeeServiceTopDownSOAP" type="tns:EmployeeServiceTopDown">
+        <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/>
+        <operation name="countEmployees">
+            <soap:operation soapAction="http://topdown.server.jaxws.baeldung.com/EmployeeServiceTopDown/countEmployees"/>
+            <input>
+                <soap:body use="literal"/>
+            </input>
+            <output>
+                <soap:body use="literal"/>
+            </output>
+        </operation>
+    </binding>
+    <service name="EmployeeServiceTopDown">
+        <port name="EmployeeServiceTopDownSOAP" binding="tns:EmployeeServiceTopDownSOAP">
+            <soap:address location="http://localhost:8080/employeeservicetopdown"/>
+        </port>
+    </service>
+</definitions>
\ No newline at end of file
diff --git a/out/production/main195/com/baeldung/java/nio/selector/README.md b/out/production/main195/com/baeldung/java/nio/selector/README.md
new file mode 100644
index 0000000000..b28aae1397
--- /dev/null
+++ b/out/production/main195/com/baeldung/java/nio/selector/README.md
@@ -0,0 +1,2 @@
+###Relevant Articles:
+- [Introduction to the Java NIO Selector](http://www.baeldung.com/java-nio-selector)
diff --git a/out/production/main216/com/baeldung/googlehttpclientguide/logging.properties b/out/production/main216/com/baeldung/googlehttpclientguide/logging.properties
new file mode 100644
index 0000000000..02489378df
--- /dev/null
+++ b/out/production/main216/com/baeldung/googlehttpclientguide/logging.properties
@@ -0,0 +1,10 @@
+# Properties file which configures the operation of the JDK logging facility.
+# The system will look for this config file to be specified as a system property: 
+# -Djava.util.logging.config.file=${project_loc:dailymotion-simple-cmdline-sample}/logging.properties
+
+# Set up the console handler (uncomment "level" to show more fine-grained messages) 
+handlers = java.util.logging.ConsoleHandler
+java.util.logging.ConsoleHandler.level = ALL
+
+# Set up logging of HTTP requests and responses (uncomment "level" to show)
+com.google.api.client.http.level = ALL
diff --git a/out/production/main231/com/baeldung/wicket/examples/HelloWorld.html b/out/production/main231/com/baeldung/wicket/examples/HelloWorld.html
new file mode 100644
index 0000000000..497e98e01a
--- /dev/null
+++ b/out/production/main231/com/baeldung/wicket/examples/HelloWorld.html
@@ -0,0 +1,52 @@
+<!DOCTYPE html>
+<html xmlns:wicket="http://wicket.apache.org">
+<head>
+<meta charset="utf-8" />
+<title>Wicket Intro Examples</title>
+<style type="text/css" media="screen">
+<!--
+body {
+    margin: 0px
+}
+
+#horizon {
+    text-align: center;
+    position: absolute;
+    top: 50%;
+    left: 0px;
+    width: 100%;
+    height: 1px;
+    overflow: visible;
+    visibility: visible;
+    display: block
+}
+
+#content {
+    font-family: Verdana, Geneva, Arial, sans-serif;
+    margin-left: -250px;
+    position: absolute;
+    top: -35px;
+    left: 50%;
+    width: 500px;
+    height: 70px;
+    visibility: visible
+}
+-->
+</style>
+</head>
+<body>
+    <div id="horizon">
+        <div id="content">
+            <div>
+                <h3>Wicket Introduction Examples:</h3>
+                <wicket:link>
+                    <a href="helloworld/HelloWorld.html">Hello World!</a>
+                    <br />
+                    <br />
+                    <a href="cafeaddress/CafeAddress.html">Cafes</a>
+                </wicket:link>
+            </div>
+        </div>
+    </div>
+</body>
+</html>
diff --git a/out/production/main231/com/baeldung/wicket/examples/cafeaddress/CafeAddress.html b/out/production/main231/com/baeldung/wicket/examples/cafeaddress/CafeAddress.html
new file mode 100644
index 0000000000..c5ada2323d
--- /dev/null
+++ b/out/production/main231/com/baeldung/wicket/examples/cafeaddress/CafeAddress.html
@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html xmlns:wicket="http://wicket.apache.org">
+<head>
+<meta charset="utf-8" />
+<title>Cafes</title>
+</head>
+<body>
+    <div style="width: 800px; margin: 0 auto;">
+        <select wicket:id="cafes"></select>
+        <p>
+            Address: <span wicket:id="address">address</span>
+        </p>
+    </div>
+</body>
+</html>
diff --git a/out/production/main231/com/baeldung/wicket/examples/helloworld/HelloWorld.html b/out/production/main231/com/baeldung/wicket/examples/helloworld/HelloWorld.html
new file mode 100644
index 0000000000..c56d07fc10
--- /dev/null
+++ b/out/production/main231/com/baeldung/wicket/examples/helloworld/HelloWorld.html
@@ -0,0 +1,5 @@
+<html>
+    <body>
+        <span wicket:id="hello"></span>
+    </body>
+</html>
diff --git a/out/production/main234/com/baeldung/activiti/security.rar b/out/production/main234/com/baeldung/activiti/security.rar
new file mode 100644
index 0000000000..38c4946168
Binary files /dev/null and b/out/production/main234/com/baeldung/activiti/security.rar differ
diff --git a/out/production/main237/com/baeldung/datetime/README.md b/out/production/main237/com/baeldung/datetime/README.md
new file mode 100644
index 0000000000..1e4adbb612
--- /dev/null
+++ b/out/production/main237/com/baeldung/datetime/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Introduction to the Java 8 Date/Time API](http://www.baeldung.com/java-8-date-time-intro)
diff --git a/out/production/main291/xml-bean-config.xml b/out/production/main291/xml-bean-config.xml
new file mode 100644
index 0000000000..3b880bbd70
--- /dev/null
+++ b/out/production/main291/xml-bean-config.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
+    <bean id="JavaPersonBean" class="com.baeldug.groovyconfig.JavaPersonBean">
+        <property name="firstName" value="John" />
+        <property name="LastName" value="Doe" />
+        <property name="age" value="30" />
+        <property name="eyesColor" value="brown" />
+        <property name="hairColor" value="brown" />
+    </bean>
+</beans>
\ No newline at end of file
diff --git a/out/production/main30/com/baeldung/factorybean/README.md b/out/production/main30/com/baeldung/factorybean/README.md
new file mode 100644
index 0000000000..13f9f379e0
--- /dev/null
+++ b/out/production/main30/com/baeldung/factorybean/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [How to use the Spring FactoryBean?](http://www.baeldung.com/spring-factorybean)
diff --git a/out/production/main330/com/baeldung/.gitignore b/out/production/main330/com/baeldung/.gitignore
new file mode 100644
index 0000000000..83c05e60c8
--- /dev/null
+++ b/out/production/main330/com/baeldung/.gitignore
@@ -0,0 +1,13 @@
+*.class
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+
+# Packaged files #
+*.jar
+*.war
+*.ear
\ No newline at end of file
diff --git a/out/production/main330/com/baeldung/README.md b/out/production/main330/com/baeldung/README.md
new file mode 100644
index 0000000000..51809b2882
--- /dev/null
+++ b/out/production/main330/com/baeldung/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [SHA-256 Hashing in Java](http://www.baeldung.com/sha-256-hashing-java)
diff --git a/out/production/main330/com/baeldung/enums/README.md b/out/production/main330/com/baeldung/enums/README.md
new file mode 100644
index 0000000000..6ccfa725f5
--- /dev/null
+++ b/out/production/main330/com/baeldung/enums/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [A Guide to Java Enums](http://www.baeldung.com/a-guide-to-java-enums)
diff --git a/out/production/main330/com/baeldung/networking/README.md b/out/production/main330/com/baeldung/networking/README.md
new file mode 100644
index 0000000000..b9e827f085
--- /dev/null
+++ b/out/production/main330/com/baeldung/networking/README.md
@@ -0,0 +1,5 @@
+### Relevant Articles:
+- [A Guide To UDP In Java](http://www.baeldung.com/udp-in-java)
+- [A Guide To HTTP Cookies In Java](http://www.baeldung.com/cookies-java)
+- [A Guide to the Java URL](http://www.baeldung.com/java-url)
+- [Working with Network Interfaces in Java](http://www.baeldung.com/java-network-interfaces)
diff --git a/out/production/main330/com/baeldung/printscreen/README.md b/out/production/main330/com/baeldung/printscreen/README.md
new file mode 100644
index 0000000000..7b3b40c102
--- /dev/null
+++ b/out/production/main330/com/baeldung/printscreen/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [How to Print Screen in Java](http://www.baeldung.com/print-screen-in-java)
diff --git a/out/production/main330/log4j.properties b/out/production/main330/log4j.properties
new file mode 100644
index 0000000000..5fe42d854c
--- /dev/null
+++ b/out/production/main330/log4j.properties
@@ -0,0 +1,9 @@
+# Set root logger level to DEBUG and its only appender to A1.
+log4j.rootLogger=DEBUG, A1
+
+# A1 is set to be a ConsoleAppender.
+log4j.appender.A1=org.apache.log4j.ConsoleAppender
+
+# A1 uses PatternLayout.
+log4j.appender.A1.layout=org.apache.log4j.PatternLayout
+log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
diff --git a/out/production/main351/com/baeldung/produceimage/README.md b/out/production/main351/com/baeldung/produceimage/README.md
new file mode 100644
index 0000000000..acd546598d
--- /dev/null
+++ b/out/production/main351/com/baeldung/produceimage/README.md
@@ -0,0 +1,3 @@
+### Relevant articles
+
+- [Returning an Image or a File with Spring](http://www.baeldung.com/spring-controller-return-image-file)
diff --git a/out/production/main96/com/baeldung/git/README.md b/out/production/main96/com/baeldung/git/README.md
new file mode 100644
index 0000000000..7e6a597c28
--- /dev/null
+++ b/out/production/main96/com/baeldung/git/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Injecting Git Information Into Spring](http://www.baeldung.com/spring-git-information)
diff --git a/out/production/routing-in-play/views/index.scala.html b/out/production/routing-in-play/views/index.scala.html
new file mode 100644
index 0000000000..4539f5a10b
--- /dev/null
+++ b/out/production/routing-in-play/views/index.scala.html
@@ -0,0 +1,20 @@
+@*
+ * This template takes a single argument, a String containing a
+ * message to display.
+ *@
+@(message: String)
+
+@*
+ * Call the `main` template with two arguments. The first
+ * argument is a `String` with the title of the page, the second
+ * argument is an `Html` object containing the body of the page.
+ *@
+@main("Welcome to Play") {
+
+    @*
+     * Get an `Html` object by calling the built-in Play welcome
+     * template and passing a `String` message.
+     *@
+    @play20.welcome(message, style = "Java")
+
+}
diff --git a/out/production/routing-in-play/views/main.scala.html b/out/production/routing-in-play/views/main.scala.html
new file mode 100644
index 0000000000..9414f4be6e
--- /dev/null
+++ b/out/production/routing-in-play/views/main.scala.html
@@ -0,0 +1,23 @@
+@*
+ * This template is called from the `index` template. This template
+ * handles the rendering of the page header and body tags. It takes
+ * two arguments, a `String` for the title of the page and an `Html`
+ * object to insert into the body of the page.
+ *@
+@(title: String)(content: Html)
+
+<!DOCTYPE html>
+<html lang="en">
+    <head>
+        @* Here's where we render the page title `String`. *@
+        <title>@title</title>
+        <link rel="stylesheet" media="screen" href="@routes.Assets.versioned("stylesheets/main.css")">
+        <link rel="shortcut icon" type="image/png" href="@routes.Assets.versioned("images/favicon.png")">
+        <script src="@routes.Assets.versioned("javascripts/hello.js")" type="text/javascript"></script>
+    </head>
+    <body>
+        @* And here's where we render the `Html` object containing
+         * the page content. *@
+        @content
+    </body>
+</html>
diff --git a/out/test/test105/com/baeldung/cglib/proxy/README.md b/out/test/test105/com/baeldung/cglib/proxy/README.md
new file mode 100644
index 0000000000..abeabc6162
--- /dev/null
+++ b/out/test/test105/com/baeldung/cglib/proxy/README.md
@@ -0,0 +1,3 @@
+### Relevant articles
+
+- [Introduction to cglib](http://www.baeldung.com/cglib)
diff --git a/out/test/test143/com/baeldung/java9/README.MD b/out/test/test143/com/baeldung/java9/README.MD
new file mode 100644
index 0000000000..2f44a2336b
--- /dev/null
+++ b/out/test/test143/com/baeldung/java9/README.MD
@@ -0,0 +1,2 @@
+### Relevant Artiles:
+- [Filtering a Stream of Optionals in Java](http://www.baeldung.com/java-filter-stream-of-optional)
diff --git a/out/test/test174/org/baeldung/hamcrest/README.md b/out/test/test174/org/baeldung/hamcrest/README.md
new file mode 100644
index 0000000000..7266ecda3a
--- /dev/null
+++ b/out/test/test174/org/baeldung/hamcrest/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Testing with Hamcrest](http://www.baeldung.com/java-junit-hamcrest-guide)
diff --git a/out/test/test191/com/baeldung/web/controller/README.md b/out/test/test191/com/baeldung/web/controller/README.md
new file mode 100644
index 0000000000..9923962dde
--- /dev/null
+++ b/out/test/test191/com/baeldung/web/controller/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [WebAppConfiguration in Spring Tests](http://www.baeldung.com/spring-webappconfiguration)
diff --git a/out/test/test197/com/baeldung/java/nio2/README.md b/out/test/test197/com/baeldung/java/nio2/README.md
new file mode 100644
index 0000000000..569be82d27
--- /dev/null
+++ b/out/test/test197/com/baeldung/java/nio2/README.md
@@ -0,0 +1,11 @@
+### Relevant Articles:
+- [Introduction to the Java NIO2 File API](http://www.baeldung.com/java-nio-2-file-api)
+- [Java NIO2 Path API](http://www.baeldung.com/java-nio-2-path)
+- [A Guide To NIO2 Asynchronous File Channel](http://www.baeldung.com/java-nio2-async-file-channel)
+- [Guide to Selenium with JUnit / TestNG](http://www.baeldung.com/java-selenium-with-junit-and-testng)
+- [A Guide to NIO2 Asynchronous Socket Channel](http://www.baeldung.com/java-nio2-async-socket-channel)
+- [A Guide To NIO2 FileVisitor](http://www.baeldung.com/java-nio2-file-visitor)
+- [A Guide To NIO2 File Attribute APIs](http://www.baeldung.com/java-nio2-file-attribute)
+- [How to use the Spring FactoryBean?](http://www.baeldung.com/spring-factorybean)
+- [A Guide to WatchService in Java NIO2](http://www.baeldung.com/java-nio2-watchservice)
+- [Guide to Java NIO2 Asynchronous Channel APIs](http://www.baeldung.com/java-nio-2-async-channels)
diff --git a/out/test/test237/META-INF/persistence.xml b/out/test/test237/META-INF/persistence.xml
new file mode 100644
index 0000000000..922aedbc39
--- /dev/null
+++ b/out/test/test237/META-INF/persistence.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence"
+             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+             xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
+    <persistence-unit name="punit">
+        <class>org.baeldung.persistence.model.Foo</class>
+        <class>org.baeldung.persistence.model.Bar</class>
+        <properties>
+            <property name="javax.persistence.jdbc.user" value="root"/>
+            <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
+            <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/HIBERTEST"/>
+            <property name="javax.persistence.ddl-generation" value="drop-and-create-tables"/>
+            <property name="javax.persistence.logging.level" value="INFO"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.cache.use_second_level_cache" value="false"/>
+            <property name="hibernate.cache.use_query_cache" value="false"/>
+        </properties>
+
+    </persistence-unit>
+</persistence>
diff --git a/out/test/test95/com/baeldung/hexToAscii/README.md b/out/test/test95/com/baeldung/hexToAscii/README.md
new file mode 100644
index 0000000000..c6d5826333
--- /dev/null
+++ b/out/test/test95/com/baeldung/hexToAscii/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Convert Hex to ASCII in Java](http://www.baeldung.com/java-convert-hex-to-ascii)
diff --git a/out/test/test95/com/baeldung/java/conversion/README.md b/out/test/test95/com/baeldung/java/conversion/README.md
new file mode 100644
index 0000000000..7c81180249
--- /dev/null
+++ b/out/test/test95/com/baeldung/java/conversion/README.md
@@ -0,0 +1,2 @@
+Relevant Articles:
+- [Java String Conversions](http://www.baeldung.com/java-string-conversions)
diff --git a/out/test/test95/org/baeldung/java/collections/README.md b/out/test/test95/org/baeldung/java/collections/README.md
new file mode 100644
index 0000000000..317d81fae7
--- /dev/null
+++ b/out/test/test95/org/baeldung/java/collections/README.md
@@ -0,0 +1,3 @@
+### Relevant Articles:
+- [Join and Split Arrays and Collections in Java](http://www.baeldung.com/java-join-and-split)
+- [Introduction to Java Servlets](http://www.baeldung.com/intro-to-servlets)
diff --git a/out/test/test95/org/baeldung/java/lists/README.md b/out/test/test95/org/baeldung/java/lists/README.md
new file mode 100644
index 0000000000..2a1e8aeeaa
--- /dev/null
+++ b/out/test/test95/org/baeldung/java/lists/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Check If Two Lists are Equal in Java](http://www.baeldung.com/java-test-a-list-for-ordinality-and-equality)
diff --git a/out/test/test98/com/baeldung/applicationcontext/README.md b/out/test/test98/com/baeldung/applicationcontext/README.md
new file mode 100644
index 0000000000..211007e0cf
--- /dev/null
+++ b/out/test/test98/com/baeldung/applicationcontext/README.md
@@ -0,0 +1,3 @@
+### Relevant Articles:
+- [Introduction to Java Servlets](http://www.baeldung.com/intro-to-servlets)
+- [Intro to the Spring ClassPathXmlApplicationContext](http://www.baeldung.com/spring-classpathxmlapplicationcontext)
diff --git a/out/test/test98/com/baeldung/beanfactory/README.md b/out/test/test98/com/baeldung/beanfactory/README.md
new file mode 100644
index 0000000000..cff20a184b
--- /dev/null
+++ b/out/test/test98/com/baeldung/beanfactory/README.md
@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Guide to the Spring BeanFactory](http://www.baeldung.com/spring-beanfactory)
diff --git a/parent-boot-5/pom.xml b/parent-boot-5/pom.xml
index 55ac0957ff..0e3936a73a 100644
--- a/parent-boot-5/pom.xml
+++ b/parent-boot-5/pom.xml
@@ -21,7 +21,7 @@
     <parent>
         <artifactId>spring-boot-starter-parent</artifactId>
         <groupId>org.springframework.boot</groupId>
-        <version>1.5.9.RELEASE</version>
+        <version>1.5.10.RELEASE</version>
         <relativePath />
     </parent>
 
@@ -60,9 +60,6 @@
                         <exclude>**/*IntegrationTest.java</exclude>
                         <exclude>**/*LongRunningUnitTest.java</exclude>
                         <exclude>**/*ManualTest.java</exclude>
-                        <exclude>**/JdbcTest.java</exclude>
-                        <exclude>**/AutoconfigurationTest.java</exclude>     
-                        <exclude>**/*EntryPointsTest.java</exclude>
                         <exclude>**/*LiveTest.java</exclude>
                     </excludes>
                 </configuration>
diff --git a/persistence-modules/spring-data-dynamodb/pom.xml b/persistence-modules/spring-data-dynamodb/pom.xml
index bf90779c29..c3ea9abf08 100644
--- a/persistence-modules/spring-data-dynamodb/pom.xml
+++ b/persistence-modules/spring-data-dynamodb/pom.xml
@@ -23,6 +23,10 @@
         <spring-data-dynamodb.version>4.4.1</spring-data-dynamodb.version>
         <aws-java-sdk-dynamodb.version>1.11.64</aws-java-sdk-dynamodb.version>
         <bootstrap.version>3.3.7-1</bootstrap.version>
+        <sqlite4java.version>1.0.392</sqlite4java.version>
+        <dynamodb.version>1.11.106</dynamodb.version>
+        <dynamodblocal.version>1.11.86</dynamodblocal.version>
+        <dynamodblocal.repository.url>https://s3-us-west-2.amazonaws.com/dynamodb-local/release</dynamodblocal.repository.url>
     </properties>
 
     <dependencyManagement>
@@ -103,6 +107,57 @@
             <artifactId>httpclient</artifactId>
             <version>${httpclient.version}</version>
         </dependency>
+        <!-- ================================================== -->
+        <!-- DynamoDBLocal dependencies                         -->
+        <!-- ================================================== -->
+        <dependency>
+            <groupId>com.amazonaws</groupId>
+            <artifactId>DynamoDBLocal</artifactId>
+            <version>${dynamodblocal.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>sqlite4java</artifactId>
+            <version>${sqlite4java.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>sqlite4java-win32-x86</artifactId>
+            <version>${sqlite4java.version}</version>
+            <type>dll</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>sqlite4java-win32-x64</artifactId>
+            <version>${sqlite4java.version}</version>
+            <type>dll</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>libsqlite4java-osx</artifactId>
+            <version>${sqlite4java.version}</version>
+            <type>dylib</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>libsqlite4java-linux-i386</artifactId>
+            <version>${sqlite4java.version}</version>
+            <type>so</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.almworks.sqlite4java</groupId>
+            <artifactId>libsqlite4java-linux-amd64</artifactId>
+            <version>${sqlite4java.version}</version>
+            <type>so</type>
+            <scope>test</scope>
+        </dependency>
+
     </dependencies>
 
     <build>
@@ -120,6 +175,25 @@
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-war-plugin</artifactId>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-dependency-plugin</artifactId>
+                <version>2.10</version>
+                <executions>
+                    <execution>
+                        <id>copy-dependencies</id>
+                        <phase>test-compile</phase>
+                        <goals>
+                            <goal>copy-dependencies</goal>
+                        </goals>
+                        <configuration>
+                            <includeScope>test</includeScope>
+                            <includeTypes>so,dll,dylib</includeTypes>
+                            <outputDirectory>${project.basedir}/native-libs</outputDirectory>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
 
         </plugins>
 
@@ -142,6 +216,11 @@
                 <enabled>false</enabled>
             </snapshots>
         </repository>
+        <repository>
+            <id>dynamodb-local</id>
+            <name>DynamoDB Local Release Repository</name>
+            <url>${dynamodblocal.repository.url}</url>
+        </repository>
     </repositories>
     <pluginRepositories>
         <pluginRepository>
diff --git a/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/ProductInfoRepositoryIntegrationTest.java b/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/ProductInfoRepositoryIntegrationTest.java
index 2ff418b4ec..6cbd5b0a5a 100644
--- a/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/ProductInfoRepositoryIntegrationTest.java
+++ b/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/ProductInfoRepositoryIntegrationTest.java
@@ -8,8 +8,9 @@ import com.amazonaws.services.dynamodbv2.model.ResourceInUseException;
 import com.baeldung.Application;
 import com.baeldung.spring.data.dynamodb.model.ProductInfo;
 import com.baeldung.spring.data.dynamodb.repositories.ProductInfoRepository;
+import com.baeldung.spring.data.dynamodb.repository.rule.LocalDbCreationRule;
 import org.junit.Before;
-import org.junit.Ignore;
+import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -21,7 +22,10 @@ import org.springframework.test.context.web.WebAppConfiguration;
 
 import java.util.List;
 
-import static org.junit.Assert.assertTrue;
+import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.core.Is.is;
+import static org.hamcrest.core.IsEqual.equalTo;
+import static org.junit.Assert.assertThat;
 
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringBootTest(classes = Application.class)
@@ -30,6 +34,9 @@ import static org.junit.Assert.assertTrue;
 @TestPropertySource(properties = { "amazon.dynamodb.endpoint=http://localhost:8000/", "amazon.aws.accesskey=test1", "amazon.aws.secretkey=test231" })
 public class ProductInfoRepositoryIntegrationTest {
 
+    @ClassRule
+    public static LocalDbCreationRule dynamoDB = new LocalDbCreationRule();
+
     private DynamoDBMapper dynamoDBMapper;
 
     @Autowired
@@ -42,7 +49,6 @@ public class ProductInfoRepositoryIntegrationTest {
     private static final String EXPECTED_PRICE = "50";
 
     @Before
-    @Ignore // TODO Remove Ignore annotations when running locally with Local DynamoDB instance
     public void setup() throws Exception {
 
         try {
@@ -57,19 +63,18 @@ public class ProductInfoRepositoryIntegrationTest {
             // Do nothing, table already created
         }
 
-        // TODO How to handle different environments. i.e. AVOID deleting all entries in ProductInfoion table
+        // TODO How to handle different environments. i.e. AVOID deleting all entries in ProductInfo on table
         dynamoDBMapper.batchDelete((List<ProductInfo>) repository.findAll());
     }
 
     @Test
-    @Ignore // TODO Remove Ignore annotations when running locally with Local DynamoDB instance
     public void givenItemWithExpectedCost_whenRunFindAll_thenItemIsFound() {
 
         ProductInfo productInfo = new ProductInfo(EXPECTED_COST, EXPECTED_PRICE);
         repository.save(productInfo);
 
         List<ProductInfo> result = (List<ProductInfo>) repository.findAll();
-        assertTrue("Not empty", result.size() > 0);
-        assertTrue("Contains item with expected cost", result.get(0).getCost().equals(EXPECTED_COST));
+        assertThat(result.size(), is(greaterThan(0)));
+        assertThat(result.get(0).getCost(), is(equalTo(EXPECTED_COST)));
     }
 }
diff --git a/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/rule/LocalDbCreationRule.java b/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/rule/LocalDbCreationRule.java
new file mode 100644
index 0000000000..555d558b06
--- /dev/null
+++ b/persistence-modules/spring-data-dynamodb/src/test/java/com/baeldung/spring/data/dynamodb/repository/rule/LocalDbCreationRule.java
@@ -0,0 +1,37 @@
+package com.baeldung.spring.data.dynamodb.repository.rule;
+
+import com.amazonaws.services.dynamodbv2.local.main.ServerRunner;
+import com.amazonaws.services.dynamodbv2.local.server.DynamoDBProxyServer;
+import org.junit.rules.ExternalResource;
+
+import java.util.Optional;
+
+public class LocalDbCreationRule extends ExternalResource {
+
+    protected DynamoDBProxyServer server;
+
+    public LocalDbCreationRule() {
+        System.setProperty("sqlite4java.library.path", "native-libs");
+    }
+
+    @Override
+    protected void before() throws Exception {
+        String port = "8000";
+        this.server = ServerRunner.createServerFromCommandLineArgs(new String[]{"-inMemory", "-port", port});
+        server.start();
+    }
+
+    @Override
+    protected void after() {
+        this.stopUnchecked(server);
+    }
+
+    protected void stopUnchecked(DynamoDBProxyServer dynamoDbServer) {
+        try {
+            dynamoDbServer.stop();
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+}
diff --git a/persistence-modules/spring-jpa/pom.xml b/persistence-modules/spring-jpa/pom.xml
index 04c64fafc3..bc0b2381f3 100644
--- a/persistence-modules/spring-jpa/pom.xml
+++ b/persistence-modules/spring-jpa/pom.xml
@@ -13,7 +13,7 @@
 		<groupId>com.baeldung</groupId>
 		<artifactId>parent-modules</artifactId>
 		<version>1.0.0-SNAPSHOT</version>
-                        <relativePath>../</relativePath>
+		<relativePath>../../</relativePath>
 	</parent>
 
 	<dependencies>
diff --git a/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/dao/StudentRepository.java b/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/dao/StudentRepository.java
index bfcf6f5cdc..f856b78c52 100644
--- a/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/dao/StudentRepository.java
+++ b/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/dao/StudentRepository.java
@@ -2,6 +2,17 @@ package org.baeldung.inmemory.persistence.dao;
 
 import org.baeldung.inmemory.persistence.model.Student;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
 
 public interface StudentRepository extends JpaRepository<Student, Long> {
+
+    @Query("SELECT s FROM Student s JOIN s.tags t WHERE t = LOWER(:tag)")
+    List<Student> retrieveByTag(@Param("tag") String tag);
+
+    @Query("SELECT s FROM Student s JOIN s.tags t WHERE s.name = LOWER(:name) AND t = LOWER(:tag)")
+    List<Student> retrieveByNameFilterByTag(@Param("name") String name, @Param("tag") String tag);
+
 }
diff --git a/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/model/Student.java b/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/model/Student.java
index b50fe9122e..2e4e3ea2cb 100644
--- a/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/model/Student.java
+++ b/persistence-modules/spring-jpa/src/main/java/org/baeldung/inmemory/persistence/model/Student.java
@@ -1,7 +1,10 @@
 package org.baeldung.inmemory.persistence.model;
 
+import javax.persistence.ElementCollection;
 import javax.persistence.Entity;
 import javax.persistence.Id;
+import java.util.ArrayList;
+import java.util.List;
 
 @Entity
 public class Student {
@@ -10,6 +13,9 @@ public class Student {
     private long id;
     private String name;
 
+    @ElementCollection
+    private List<String> tags = new ArrayList<>();
+
     public Student() {
     }
 
@@ -35,4 +41,11 @@ public class Student {
         this.name = name;
     }
 
+    public List<String> getTags() {
+        return tags;
+    }
+
+    public void setTags(List<String> tags) {
+        this.tags.addAll(tags);
+    }
 }
diff --git a/persistence-modules/spring-jpa/src/test/java/org/baeldung/persistence/repository/InMemoryDBIntegrationTest.java b/persistence-modules/spring-jpa/src/test/java/org/baeldung/persistence/repository/InMemoryDBIntegrationTest.java
index 8380ab5434..28d7e3772c 100644
--- a/persistence-modules/spring-jpa/src/test/java/org/baeldung/persistence/repository/InMemoryDBIntegrationTest.java
+++ b/persistence-modules/spring-jpa/src/test/java/org/baeldung/persistence/repository/InMemoryDBIntegrationTest.java
@@ -12,6 +12,9 @@ import org.springframework.transaction.annotation.Transactional;
 
 import javax.annotation.Resource;
 
+import java.util.Arrays;
+import java.util.List;
+
 import static org.junit.Assert.assertEquals;
 
 @RunWith(SpringJUnit4ClassRunner.class)
@@ -34,4 +37,46 @@ public class InMemoryDBIntegrationTest {
         assertEquals("name incorrect", NAME, student2.getName());        
     }
 
+    @Test
+    public void givenStudentWithTags_whenSave_thenGetByTagOk(){
+        Student student = new Student(ID, NAME);
+        student.setTags(Arrays.asList("full time", "computer science"));
+        studentRepository.save(student);
+
+        Student student2 = studentRepository.retrieveByTag("full time").get(0);
+        assertEquals("name incorrect", NAME, student2.getName());
+    }
+
+    @Test
+    public void givenMultipleStudentsWithTags_whenSave_thenGetByTagReturnsCorrectCount(){
+        Student student = new Student(0, "Larry");
+        student.setTags(Arrays.asList("full time", "computer science"));
+        studentRepository.save(student);
+
+        Student student2 = new Student(1, "Curly");
+        student2.setTags(Arrays.asList("part time", "rocket science"));
+        studentRepository.save(student2);
+
+        Student student3 = new Student(2, "Moe");
+        student3.setTags(Arrays.asList("full time", "philosophy"));
+        studentRepository.save(student3);
+
+        Student student4 = new Student(3, "Shemp");
+        student4.setTags(Arrays.asList("part time", "mathematics"));
+        studentRepository.save(student4);
+
+        List<Student> students = studentRepository.retrieveByTag("full time");
+        assertEquals("size incorrect", 2, students.size());
+    }
+
+    @Test
+    public void givenStudentWithTags_whenSave_thenGetByNameAndTagOk(){
+        Student student = new Student(ID, NAME);
+        student.setTags(Arrays.asList("full time", "computer science"));
+        studentRepository.save(student);
+
+        Student student2 = studentRepository.retrieveByNameFilterByTag("John", "full time").get(0);
+        assertEquals("name incorrect", NAME, student2.getName());
+    }
+
 }
diff --git a/pom.xml b/pom.xml
index fc0c8f8ba7..3092c0fa40 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,6 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>parent-modules</artifactId>
@@ -15,7 +14,7 @@
         <gib.skipTestsForNotImpactedModules>true</gib.skipTestsForNotImpactedModules>
         <gib.failOnMissingGitDir>false</gib.failOnMissingGitDir>
         <gib.failOnError>false</gib.failOnError>
-        <!-- <gib.enabled>false</gib.enabled>-->
+        <!-- <gib.enabled>false</gib.enabled> -->
         <junit.version>4.12</junit.version>
         <org.hamcrest.version>1.3</org.hamcrest.version>
         <mockito.version>2.8.9</mockito.version>
@@ -29,7 +28,7 @@
 
     <modules>
         <module>parent-boot-5</module>
-        <module>asm</module>     
+        <module>asm</module>
         <module>atomix</module>
         <module>apache-cayenne</module>
         <module>aws</module>
@@ -49,9 +48,9 @@
         <module>core-java</module>
         <module>core-java-io</module>
         <module>core-java-8</module>
-		<!--
+        <module>core-groovy</module>
         <module>core-java-concurrency</module>
-		-->
+
         <module>couchbase</module>
 
         <module>deltaspike</module>
@@ -59,7 +58,7 @@
 
         <module>ethereumj</module>
 
-        <!--<module>ejb</module>-->
+        <!--<module>ejb</module> -->
 
         <module>feign</module>
 
@@ -67,6 +66,7 @@
 
         <module>geotools</module>
         <module>testing-modules/groovy-spock</module>
+        <module>google-cloud</module>
         <module>gson</module>
         <module>guava</module>
         <module>guava-modules/guava-18</module>
@@ -78,20 +78,20 @@
         <module>handling-spring-static-resources</module>
         <module>hazelcast</module>
         <module>hbase</module>
-        <!--<module>hibernate5</module>-->
+        <!--<module>hibernate5</module> -->
         <module>httpclient</module>
         <module>hystrix</module>
 
-        <module>image-processing</module>
+        <!-- <module>image-processing</module> --> <!-- TODO: to add back -->
         <module>immutables</module>
         <module>influxdb</module>
 
         <module>jackson</module>
-        <!--         <module>persistence-modules/java-cassandra</module> -->
+        <!-- <module>persistence-modules/java-cassandra</module> -->
         <module>vavr</module>
-	      <module>java-lite</module>
-	      <module>java-rmi</module>	    
-	      <module>java-vavr-stream</module>
+        <module>java-lite</module>
+        <module>java-rmi</module>
+        <module>java-vavr-stream</module>
         <module>javax-servlets</module>
         <module>javaxval</module>
         <module>jaxb</module>
@@ -109,23 +109,21 @@
 
         <module>libraries</module>
         <module>libraries-data</module>
-        <module>linkrest</module>        
+        <module>linkrest</module>
         <module>logging-modules/log-mdc</module>
         <module>logging-modules/log4j</module>
         <module>logging-modules/log4j2</module>
         <module>logging-modules/logback</module>
         <module>lombok</module>
-       <!-- <module>kotlin</module>-->
+        <!-- <module>kotlin</module> -->
         <module>mapstruct</module>
-	<!--
-        <module>metrics</module>
-        -->
+        <!-- <module>metrics</module> -->
         <module>mesos-marathon</module>
         <module>testing-modules/mockito</module>
         <module>testing-modules/mockito-2</module>
         <module>testing-modules/mocks</module>
         <module>mustache</module>
-	    <module>mvn-wrapper</module>
+        <module>mvn-wrapper</module>
         <module>noexception</module>
         <module>orientdb</module>
         <module>osgi</module>
@@ -145,14 +143,13 @@
         <module>resteasy</module>
         <module>rxjava</module>
         <module>spring-swagger-codegen</module>
-
         <module>testing-modules/selenium-junit-testng</module>
         <module>persistence-modules/solr</module>
         <module>spark-java</module>
-      <!--  <module>spring-5</module>-->
+        <module>spring-5</module>
         <module>spring-5-reactive</module>
         <module>spring-5-mvc</module>
-        <module>spring-5-security</module>
+        <!-- <module>spring-5-security</module> --> <!-- TODO: uncomment -->
         <module>spring-activiti</module>
         <module>spring-akka</module>
         <module>spring-amqp</module>
@@ -162,7 +159,7 @@
         <module>spring-batch</module>
         <module>spring-bom</module>
         <module>spring-boot</module>
-	    <module>spring-boot-keycloak</module>
+        <module>spring-boot-keycloak</module>
         <module>spring-boot-bootstrap</module>
         <module>spring-boot-admin</module>
         <module>spring-boot-security</module>
@@ -191,7 +188,7 @@
         <module>spring-integration</module>
         <module>spring-jenkins-pipeline</module>
         <module>spring-jersey</module>
-        <module>jmeter</module>
+        <!-- <module>jmeter</module> --> <!-- TODO: uncomment -->
         <module>spring-jms</module>
         <module>spring-jooq</module>
         <module>persistence-modules/spring-jpa</module>
@@ -250,9 +247,9 @@
         <module>spring-reactor</module>
         <module>spring-vertx</module>
         <module>spring-jinq</module>
-		
-		<module>spring-rest-embedded-tomcat</module>
-        
+
+        <module>spring-rest-embedded-tomcat</module>
+
 
         <module>testing-modules/testing</module>
         <module>testing-modules/testng</module>
@@ -279,7 +276,7 @@
         <module>saas</module>
         <module>deeplearning4j</module>
         <module>lucene</module>
-		<module>vraptor</module>
+        <module>vraptor</module>
         <module>persistence-modules/java-cockroachdb</module>
     </modules>
 
@@ -306,7 +303,7 @@
             <version>${org.slf4j.version}</version>
         </dependency>
 
-        <!--  test -->
+        <!-- test -->
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
diff --git a/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java b/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
index 9d5d094875..81dfda3bb3 100644
--- a/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
+++ b/reactor-core/src/test/java/com/baeldung/reactor/core/CombiningPublishersTest.java
@@ -17,7 +17,7 @@ public class CombiningPublishersTest {
     
     
     @Test
-    public void testMerge() {
+    public void givenFluxes_whenMergeIsInvoked_thenMerge() {
         Flux<Integer> fluxOfIntegers = Flux.merge(
                 evenNumbers, 
                 oddNumbers);
@@ -33,7 +33,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testMergeWithDelayedElements() {
+    public void givenFluxes_whenMergeWithDelayedElementsIsInvoked_thenMergeWithDelayedElements() {
         Flux<Integer> fluxOfIntegers = Flux.merge(
                 evenNumbers.delayElements(Duration.ofMillis(500L)), 
                 oddNumbers.delayElements(Duration.ofMillis(300L)));
@@ -49,7 +49,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testConcat() {
+    public void givenFluxes_whenConcatIsInvoked_thenConcat() {
         Flux<Integer> fluxOfIntegers = Flux.concat(
                 evenNumbers.delayElements(Duration.ofMillis(500L)), 
                 oddNumbers.delayElements(Duration.ofMillis(300L)));
@@ -65,7 +65,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testConcatWith() {
+    public void givenFluxes_whenConcatWithIsInvoked_thenConcatWith() {
         Flux<Integer> fluxOfIntegers = evenNumbers
                 .concatWith(oddNumbers);
         
@@ -80,7 +80,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testCombineLatest() {
+    public void givenFluxes_whenCombineLatestIsInvoked_thenCombineLatest() {
         Flux<Integer> fluxOfIntegers = Flux.combineLatest(
                 evenNumbers, 
                 oddNumbers, 
@@ -96,7 +96,7 @@ public class CombiningPublishersTest {
     }
 
     @Test
-    public void testCombineLatest1() {
+    public void givenFluxes_whenCombineLatestIsInvoked_thenCombineLatest1() {
             StepVerifier.create(Flux.combineLatest(obj -> (int) obj[1], evenNumbers, oddNumbers))
             .expectNext(1)
             .expectNext(3)
@@ -105,7 +105,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testMergeSequential() {
+    public void givenFluxes_whenMergeSequentialIsInvoked_thenMergeSequential() {
         Flux<Integer> fluxOfIntegers = Flux.mergeSequential(
                 evenNumbers, 
                 oddNumbers);
@@ -122,7 +122,7 @@ public class CombiningPublishersTest {
     
     
     @Test
-    public void testMergeDelayError() {
+    public void givenFluxes_whenMergeDelayErrorIsInvoked_thenMergeDelayError() {
         Flux<Integer> fluxOfIntegers = Flux.mergeDelayError(1, 
                 evenNumbers.delayElements(Duration.ofMillis(500L)), 
                 oddNumbers.delayElements(Duration.ofMillis(300L)));
@@ -138,7 +138,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testMergeWith() {
+    public void givenFluxes_whenMergeWithIsInvoked_thenMergeWith() {
         Flux<Integer> fluxOfIntegers = evenNumbers.mergeWith(oddNumbers);
         
         StepVerifier.create(fluxOfIntegers)
@@ -152,7 +152,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testZip() {
+    public void givenFluxes_whenZipIsInvoked_thenZip() {
         Flux<Integer> fluxOfIntegers = Flux.zip(
                 evenNumbers, 
                 oddNumbers, 
@@ -166,7 +166,7 @@ public class CombiningPublishersTest {
     }
     
     @Test
-    public void testZipWith() {
+    public void givenFluxes_whenZipWithIsInvoked_thenZipWith() {
         Flux<Integer> fluxOfIntegers = evenNumbers
                 .zipWith(oddNumbers, 
                 (a, b) -> a * b);
@@ -177,6 +177,4 @@ public class CombiningPublishersTest {
         .expectComplete()
         .verify();
     }
-    
-    
 }
diff --git a/rxjava/pom.xml b/rxjava/pom.xml
index 0f950914ff..d88dfcaa9b 100644
--- a/rxjava/pom.xml
+++ b/rxjava/pom.xml
@@ -31,6 +31,19 @@
             <version>1.0.0</version>
         </dependency>
 
+        <dependency>
+            <groupId>io.reactivex</groupId>
+            <artifactId>rxjava-string</artifactId>
+            <version>1.1.1</version>
+        </dependency>
+      
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+
         <dependency>
             <groupId>com.jayway.awaitility</groupId>
             <artifactId>awaitility</artifactId>
diff --git a/rxjava/src/test/java/com/baeldung/rxjava/FlowableTest.java b/rxjava/src/test/java/com/baeldung/rxjava/FlowableTest.java
new file mode 100644
index 0000000000..b9d1d64c24
--- /dev/null
+++ b/rxjava/src/test/java/com/baeldung/rxjava/FlowableTest.java
@@ -0,0 +1,93 @@
+package com.baeldung.rxjava;
+
+import io.reactivex.BackpressureStrategy;
+import io.reactivex.Flowable;
+import io.reactivex.FlowableOnSubscribe;
+import io.reactivex.Observable;
+import io.reactivex.exceptions.MissingBackpressureException;
+import io.reactivex.schedulers.Schedulers;
+import io.reactivex.subscribers.TestSubscriber;
+
+import org.junit.Test;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+public class FlowableTest {
+
+    @Test public void whenFlowableIsCreated_thenItIsProperlyInitialized() {
+        Flowable<Integer> integerFlowable = Flowable.just(1, 2, 3, 4);
+        assertNotNull(integerFlowable);
+    }
+
+    @Test public void whenFlowableIsCreatedFromObservable_thenItIsProperlyInitialized() throws InterruptedException {
+        Observable<Integer> integerObservable = Observable.just(1, 2, 3);
+        Flowable<Integer> integerFlowable = integerObservable.toFlowable(BackpressureStrategy.BUFFER);
+        assertNotNull(integerFlowable);
+
+    }
+
+    @Test public void whenFlowableIsCreatedFromFlowableOnSubscribe_thenItIsProperlyInitialized() throws InterruptedException {
+        FlowableOnSubscribe<Integer> flowableOnSubscribe = flowableEmitter -> flowableEmitter.onNext(1);
+        Flowable<Integer> integerFlowable = Flowable.create(flowableOnSubscribe, BackpressureStrategy.BUFFER);
+        assertNotNull(integerFlowable);
+    }
+
+    @Test public void thenAllValuesAreBufferedAndReceived() {
+        List testList = IntStream.range(0, 100000).boxed().collect(Collectors.toList());
+        Observable observable = Observable.fromIterable(testList);
+        TestSubscriber<Integer> testSubscriber = observable.toFlowable(BackpressureStrategy.BUFFER).observeOn(Schedulers.computation()).test();
+
+        testSubscriber.awaitTerminalEvent();
+
+        List<Integer> receivedInts = testSubscriber.getEvents().get(0).stream().mapToInt(object -> (int) object).boxed().collect(Collectors.toList());
+
+        assertEquals(testList, receivedInts);
+    }
+
+    @Test public void whenDropStrategyUsed_thenOnBackpressureDropped() {
+        List testList = IntStream.range(0, 100000).boxed().collect(Collectors.toList());
+
+        Observable observable = Observable.fromIterable(testList);
+        TestSubscriber<Integer> testSubscriber = observable.toFlowable(BackpressureStrategy.DROP).observeOn(Schedulers.computation()).test();
+        testSubscriber.awaitTerminalEvent();
+        List<Integer> receivedInts = testSubscriber.getEvents().get(0).stream().mapToInt(object -> (int) object).boxed().collect(Collectors.toList());
+
+        assertThat(receivedInts.size() < testList.size());
+        assertThat(!receivedInts.contains(100000));
+    }
+
+    @Test public void whenMissingStrategyUsed_thenException() {
+        Observable observable = Observable.range(1, 100000);
+        TestSubscriber subscriber = observable.toFlowable(BackpressureStrategy.MISSING).observeOn(Schedulers.computation()).test();
+
+        subscriber.awaitTerminalEvent();
+        subscriber.assertError(MissingBackpressureException.class);
+    }
+
+    @Test public void  whenErrorStrategyUsed_thenExceptionIsThrown() {
+            Observable observable = Observable.range(1, 100000);
+        TestSubscriber subscriber = observable.toFlowable(BackpressureStrategy.ERROR).observeOn(Schedulers.computation()).test();
+
+        subscriber.awaitTerminalEvent();
+        subscriber.assertError(MissingBackpressureException.class);
+    }
+
+    @Test public void whenLatestStrategyUsed_thenTheLastElementReceived() {
+        List testList = IntStream.range(0, 100000).boxed().collect(Collectors.toList());
+        Observable observable = Observable.fromIterable(testList);
+        TestSubscriber<Integer> testSubscriber = observable.toFlowable(BackpressureStrategy.LATEST).observeOn(Schedulers.computation()).test();
+
+        testSubscriber.awaitTerminalEvent();
+        List<Integer> receivedInts = testSubscriber.getEvents().get(0).stream().mapToInt(object -> (int) object).boxed().collect(Collectors.toList());
+
+        assertThat(receivedInts.size() < testList.size());
+        assertThat(receivedInts.contains(100000));
+    }
+
+}
\ No newline at end of file
diff --git a/rxjava/src/test/java/com/baeldung/rxjava/operators/RxStringOperatorsTest.java b/rxjava/src/test/java/com/baeldung/rxjava/operators/RxStringOperatorsTest.java
new file mode 100644
index 0000000000..5e58b32d8b
--- /dev/null
+++ b/rxjava/src/test/java/com/baeldung/rxjava/operators/RxStringOperatorsTest.java
@@ -0,0 +1,145 @@
+package com.baeldung.rxjava.operators;
+
+import java.io.ByteArrayInputStream;
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import rx.Observable;
+import rx.observables.StringObservable;
+import rx.observers.TestSubscriber;
+
+
+public class RxStringOperatorsTest
+{
+
+    @Test
+    public void givenStringObservable_whenFromInputStream_ThenSuccessfull()
+    {
+        //given
+        ByteArrayInputStream is = new ByteArrayInputStream("Lorem ipsum loream, Lorem ipsum lore".getBytes(StandardCharsets.UTF_8));
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.decode(StringObservable.from(is), StandardCharsets.UTF_8)
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(1);
+        subscriber.assertValues("Lorem ipsum loream, Lorem ipsum lore");
+    }
+    @Test
+    public void givenStringObservable_whenEncodingString_ThenSuccessfullObtainingByteStream()
+    {
+        //given
+        Observable<String> sourceObservable = Observable.just("Lorem ipsum loream");
+        TestSubscriber<byte[]> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.encode(sourceObservable, StandardCharsets.UTF_8)
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(1);
+        subscriber.getOnNextEvents()
+            .stream()
+            .forEach(bytes -> Assert.assertTrue(Arrays.equals(bytes, "Lorem ipsum loream".getBytes(StandardCharsets.UTF_8))));
+    }
+
+    @Test
+    public void givenStringObservable_whenConcatenatingStrings_ThenSuccessfullObtainingSingleString()
+    {
+        //given
+        Observable<String> sourceObservable = Observable.just("Lorem ipsum loream","Lorem ipsum lore");
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.stringConcat(sourceObservable)
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(1);
+        subscriber.assertValues("Lorem ipsum loreamLorem ipsum lore");
+    }
+
+
+    @Test
+    public void givenStringObservable_whenDecodingByteArray_ThenSuccessfullObtainingStringStream()
+    {
+        //given
+        Observable<byte[]> sourceObservable = Observable.just("Lorem ipsum loream".getBytes(StandardCharsets.UTF_8));
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.decode(sourceObservable, StandardCharsets.UTF_8)
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(1);
+        subscriber.assertValues("Lorem ipsum loream");
+    }
+
+    @Test
+    public void givenStringObservable_whenStringSplitted_ThenSuccessfullObtainingStringsStream()
+    {
+        //given
+        Observable<String> sourceObservable = Observable.just("Lorem ipsum loream,Lorem ipsum lore");
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.split(sourceObservable,",")
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(2);
+        subscriber.assertValues("Lorem ipsum loream", "Lorem ipsum lore");
+    }
+
+    @Test
+    public void givenStringObservable_whenSplittingByLine_ThenSuccessfullObtainingStringsStream() {
+        //given
+        Observable<String> sourceObservable = Observable.just("Lorem ipsum loream\nLorem ipsum lore");
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.byLine(sourceObservable)
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(2);
+        subscriber.assertValues("Lorem ipsum loream", "Lorem ipsum lore");
+    }
+
+
+    @Test
+    public void givenStringObservable_whenJoiningStrings_ThenSuccessfullObtainingSingleString() {
+        //given
+        Observable<String> sourceObservable = Observable.just("Lorem ipsum loream","Lorem ipsum lore");
+        TestSubscriber<String> subscriber = TestSubscriber.create();
+
+        // when
+        StringObservable.join(sourceObservable,",")
+            .subscribe(subscriber);
+
+        // then
+        subscriber.assertCompleted();
+        subscriber.assertNoErrors();
+        subscriber.assertValueCount(1);
+        subscriber.assertValues("Lorem ipsum loream,Lorem ipsum lore");
+    }
+
+}
diff --git a/spring-5-security/pom.xml b/spring-5-security/pom.xml
index 0a1d1f5df0..ffe6865704 100644
--- a/spring-5-security/pom.xml
+++ b/spring-5-security/pom.xml
@@ -12,7 +12,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>2.0.0.M7</version>
+		<version>2.0.0.RC2</version>
 		<relativePath /> <!-- lookup parent from repository -->
 	</parent>
 
diff --git a/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingConfigurer.java b/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingConfigurer.java
new file mode 100644
index 0000000000..5a9479b664
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingConfigurer.java
@@ -0,0 +1,32 @@
+package com.baeldung.dsl;
+
+import java.util.List;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configurers.AbstractHttpConfigurer;
+import org.springframework.security.web.access.intercept.FilterSecurityInterceptor;
+
+public class ClientErrorLoggingConfigurer extends AbstractHttpConfigurer<ClientErrorLoggingConfigurer, HttpSecurity> {
+
+    private List<HttpStatus> errorCodes;
+
+    public ClientErrorLoggingConfigurer(List<HttpStatus> errorCodes) {
+        this.errorCodes = errorCodes;
+    }
+
+    public ClientErrorLoggingConfigurer() {
+
+    }
+
+    @Override
+    public void init(HttpSecurity http) throws Exception {
+        // initialization code
+    }
+
+    @Override
+    public void configure(HttpSecurity http) throws Exception {
+        http.addFilterAfter(new ClientErrorLoggingFilter(errorCodes), FilterSecurityInterceptor.class);
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingFilter.java b/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingFilter.java
new file mode 100644
index 0000000000..56f7cea3b8
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/dsl/ClientErrorLoggingFilter.java
@@ -0,0 +1,54 @@
+package com.baeldung.dsl;
+
+import java.io.IOException;
+import java.util.List;
+
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.http.HttpServletResponse;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.springframework.http.HttpStatus;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.web.filter.GenericFilterBean;
+
+public class ClientErrorLoggingFilter extends GenericFilterBean {
+
+    private static final Logger logger = LogManager.getLogger(ClientErrorLoggingFilter.class);
+
+    private List<HttpStatus> errorCodes;
+
+    public ClientErrorLoggingFilter(List<HttpStatus> errorCodes) {
+        this.errorCodes = errorCodes;
+    }
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
+
+        Authentication auth = SecurityContextHolder.getContext()
+            .getAuthentication();
+
+        if (auth != null) {
+            int status = ((HttpServletResponse) response).getStatus();
+            if (status >= 400 && status < 500) {
+                if (errorCodes == null) {
+                    logger.debug("User " + auth.getName() + " encountered error " + status);
+                } else {
+                    if (errorCodes.stream()
+                        .filter(s -> s.value() == status)
+                        .findFirst()
+                        .isPresent()) {
+                        logger.debug("User " + auth.getName() + " encountered error " + status);
+                    }
+                }
+            }
+        }
+
+        chain.doFilter(request, response);
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/dsl/CustomConfigurerApplication.java b/spring-5-security/src/main/java/com/baeldung/dsl/CustomConfigurerApplication.java
new file mode 100644
index 0000000000..2cd3d7fc7f
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/dsl/CustomConfigurerApplication.java
@@ -0,0 +1,13 @@
+package com.baeldung.dsl;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class CustomConfigurerApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(CustomConfigurerApplication.class, args);
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/dsl/MyController.java b/spring-5-security/src/main/java/com/baeldung/dsl/MyController.java
new file mode 100644
index 0000000000..c69046afb5
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/dsl/MyController.java
@@ -0,0 +1,14 @@
+package com.baeldung.dsl;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class MyController {
+
+    @GetMapping("/admin")
+    public String getAdminPage() {
+        return "Hello Admin";
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/dsl/SecurityConfig.java b/spring-5-security/src/main/java/com/baeldung/dsl/SecurityConfig.java
new file mode 100644
index 0000000000..382e222f64
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/dsl/SecurityConfig.java
@@ -0,0 +1,50 @@
+package com.baeldung.dsl;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+@Configuration
+public class SecurityConfig extends WebSecurityConfigurerAdapter {
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        http.authorizeRequests()
+            .antMatchers("/admin*")
+            .hasAnyRole("ADMIN")
+            .anyRequest()
+            .authenticated()
+            .and()
+            .formLogin()
+            .and()
+            .apply(clientErrorLogging());
+    }
+
+    @Bean
+    public ClientErrorLoggingConfigurer clientErrorLogging() {
+        return new ClientErrorLoggingConfigurer();
+    }
+
+    @Override
+    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
+        auth.inMemoryAuthentication()
+            .passwordEncoder(passwordEncoder())
+            .withUser("user1")
+            .password(passwordEncoder().encode("user"))
+            .roles("USER")
+            .and()
+            .withUser("admin")
+            .password(passwordEncoder().encode("admin"))
+            .roles("ADMIN");
+    }
+
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/passwordstorage/BaeldungPasswordEncoderSetup.java b/spring-5-security/src/main/java/com/baeldung/passwordstorage/BaeldungPasswordEncoderSetup.java
new file mode 100644
index 0000000000..94987029db
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/passwordstorage/BaeldungPasswordEncoderSetup.java
@@ -0,0 +1,35 @@
+package com.baeldung.passwordstorage;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.authentication.event.AuthenticationSuccessEvent;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+@Configuration
+public class BaeldungPasswordEncoderSetup {
+
+    private final static Logger LOG = LoggerFactory.getLogger(BaeldungPasswordEncoderSetup.class);
+
+    @Bean
+    public ApplicationListener<AuthenticationSuccessEvent> authenticationSuccessListener(final PasswordEncoder encoder) {
+
+        return (AuthenticationSuccessEvent event) -> {
+            final Authentication auth = event.getAuthentication();
+
+            if (auth instanceof UsernamePasswordAuthenticationToken && auth.getCredentials() != null) {
+
+                final CharSequence clearTextPass = (CharSequence) auth.getCredentials(); // 1
+                final String newPasswordHash = encoder.encode(clearTextPass); // 2
+
+                LOG.info("New password hash {} for user {}", newPasswordHash, auth.getName());
+
+                ((UsernamePasswordAuthenticationToken) auth).eraseCredentials(); // 3
+            }
+        };
+    }
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageApplication.java b/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageApplication.java
new file mode 100644
index 0000000000..173d979a45
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageApplication.java
@@ -0,0 +1,13 @@
+package com.baeldung.passwordstorage;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class PasswordStorageApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(PasswordStorageApplication.class, args);
+    }
+
+}
diff --git a/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageWebSecurityConfigurer.java b/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageWebSecurityConfigurer.java
new file mode 100644
index 0000000000..22ef2f0835
--- /dev/null
+++ b/spring-5-security/src/main/java/com/baeldung/passwordstorage/PasswordStorageWebSecurityConfigurer.java
@@ -0,0 +1,53 @@
+package com.baeldung.passwordstorage;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.DelegatingPasswordEncoder;
+import org.springframework.security.crypto.password.NoOpPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.crypto.password.StandardPasswordEncoder;
+import org.springframework.security.crypto.scrypt.SCryptPasswordEncoder;
+import org.springframework.security.provisioning.InMemoryUserDetailsManager;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+@Configuration
+public class PasswordStorageWebSecurityConfigurer extends WebSecurityConfigurerAdapter {
+
+
+    @Override
+    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
+        auth.eraseCredentials(false) // 4
+          .userDetailsService(getUserDefaultDetailsService())
+          .passwordEncoder(passwordEncoder());
+    }
+
+    @Bean
+    public UserDetailsService getUserDefaultDetailsService() {
+        User testUser = new User("baeldung", "{noop}SpringSecurity5", Collections.emptyList());
+        return new InMemoryUserDetailsManager(testUser);
+    }
+
+    @Bean
+    public PasswordEncoder passwordEncoder() {
+        // set up the list of supported encoders and their prefixes
+        PasswordEncoder defaultEncoder = new StandardPasswordEncoder();
+        Map<String, PasswordEncoder> encoders = new HashMap<>();
+        encoders.put("bcrypt", new BCryptPasswordEncoder());
+        encoders.put("scrypt", new SCryptPasswordEncoder());
+        encoders.put("noop", NoOpPasswordEncoder.getInstance());
+
+        DelegatingPasswordEncoder passwordEncoder = new DelegatingPasswordEncoder("bcrypt", encoders);
+        passwordEncoder.setDefaultPasswordEncoderForMatches(defaultEncoder);
+
+        return passwordEncoder;
+    }
+
+}
diff --git a/spring-5-security/src/main/resources/application.properties b/spring-5-security/src/main/resources/application.properties
index ccec014c2b..781ee76826 100644
--- a/spring-5-security/src/main/resources/application.properties
+++ b/spring-5-security/src/main/resources/application.properties
@@ -1,3 +1,5 @@
 server.port=8081
 
-logging.level.root=INFO
\ No newline at end of file
+logging.level.root=INFO
+
+logging.level.com.baeldung.dsl.ClientErrorLoggingFilter=DEBUG
diff --git a/spring-5/pom.xml b/spring-5/pom.xml
index 19dd65d78f..3b21f86e60 100644
--- a/spring-5/pom.xml
+++ b/spring-5/pom.xml
@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>2.0.0.M7</version>
+		<version>2.0.0.RC2</version>
 		<relativePath /> <!-- lookup parent from repository -->
 	</parent>
 
@@ -39,10 +39,14 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-webflux</artifactId>
 		</dependency>
-    <dependency>
+		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-hateoas</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-thymeleaf</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.projectreactor</groupId>
 			<artifactId>reactor-spring</artifactId>
diff --git a/spring-5/src/main/java/com/baeldung/execption/ActorController.java b/spring-5/src/main/java/com/baeldung/execption/ActorController.java
new file mode 100644
index 0000000000..6c9c46253a
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/execption/ActorController.java
@@ -0,0 +1,41 @@
+package com.baeldung.execption;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.server.ResponseStatusException;
+
+@RestController
+public class ActorController {
+
+    @Autowired
+    ActorService actorService;
+
+    @GetMapping("/actor/{id}")
+    public String getActorName(@PathVariable("id") int id) {
+        try {
+            return actorService.getActor(id);
+        } catch (ActorNotFoundException ex) {
+            throw new ResponseStatusException(HttpStatus.NOT_FOUND, "Actor Not Found", ex);
+        }
+    }
+
+    @DeleteMapping("/actor/{id}")
+    public String getActor(@PathVariable("id") int id) {
+        return actorService.removeActor(id);
+    }
+
+    @PutMapping("/actor/{id}/{name}")
+    public String updateActorName(@PathVariable("id") int id, @PathVariable("name") String name) {
+        try {
+            return actorService.updateActor(id, name);
+        } catch (ActorNotFoundException ex) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Provide correct Actor Id", ex);
+        }
+    }
+
+}
diff --git a/spring-5/src/main/java/com/baeldung/execption/ActorNotFoundException.java b/spring-5/src/main/java/com/baeldung/execption/ActorNotFoundException.java
new file mode 100644
index 0000000000..642c075b5d
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/execption/ActorNotFoundException.java
@@ -0,0 +1,13 @@
+package com.baeldung.execption;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(code = HttpStatus.NOT_FOUND, reason = "Actor Not Found")
+public class ActorNotFoundException extends Exception {
+    private static final long serialVersionUID = 1L;
+
+    public ActorNotFoundException(String errorMessage) {
+        super(errorMessage);
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/execption/ActorService.java b/spring-5/src/main/java/com/baeldung/execption/ActorService.java
new file mode 100644
index 0000000000..956fa92015
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/execption/ActorService.java
@@ -0,0 +1,35 @@
+package com.baeldung.execption;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Service;
+import org.springframework.web.server.ResponseStatusException;
+
+@Service
+public class ActorService {
+    List<String> actors = Arrays.asList("Jack Nicholson", "Marlon Brando", "Robert De Niro", "Al Pacino", "Tom Hanks");
+
+    public String getActor(int index) throws ActorNotFoundException {
+        if (index >= actors.size()) {
+            throw new ActorNotFoundException("Actor Not Found in Repsoitory");
+        }
+        return actors.get(index);
+    }
+
+    public String updateActor(int index, String actorName) throws ActorNotFoundException {
+        if (index >= actors.size()) {
+            throw new ActorNotFoundException("Actor Not Found in Repsoitory");
+        }
+        actors.set(index, actorName);
+        return actorName;
+    }
+
+    public String removeActor(int index) {
+        if (index >= actors.size()) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, "Actor Not Found in Repsoitory");
+        }
+        return actors.remove(index);
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/execption/SpringExceptionApplication.java b/spring-5/src/main/java/com/baeldung/execption/SpringExceptionApplication.java
new file mode 100644
index 0000000000..1670da54c3
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/execption/SpringExceptionApplication.java
@@ -0,0 +1,14 @@
+package com.baeldung.execption;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration;
+import org.springframework.context.annotation.ComponentScan;
+
+@SpringBootApplication(exclude = SecurityAutoConfiguration.class)
+@ComponentScan(basePackages = { "com.baeldung.execption" })
+public class SpringExceptionApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(SpringExceptionApplication.class, args);
+    }
+}
\ No newline at end of file
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/Config.java b/spring-5/src/main/java/com/baeldung/sessionattrs/Config.java
new file mode 100644
index 0000000000..9d5c9d9f42
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/Config.java
@@ -0,0 +1,44 @@
+package com.baeldung.sessionattrs;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
+import org.springframework.core.Ordered;
+import org.springframework.web.context.WebApplicationContext;
+import org.springframework.web.servlet.config.annotation.EnableWebMvc;
+import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import org.thymeleaf.templatemode.TemplateMode;
+import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
+import org.thymeleaf.templateresolver.ITemplateResolver;
+
+@EnableWebMvc
+@Configuration
+public class Config implements WebMvcConfigurer {
+
+    @Override
+    public void addViewControllers(ViewControllerRegistry registry) {
+        registry.addViewController("/").setViewName("index");
+        registry.setOrder(Ordered.HIGHEST_PRECEDENCE);
+    }
+
+    @Bean
+    @Scope(
+        value = WebApplicationContext.SCOPE_SESSION, 
+        proxyMode = ScopedProxyMode.TARGET_CLASS)
+    public TodoList todos() {
+        return new TodoList();
+    }
+
+    @Bean
+    public ITemplateResolver templateResolver() {
+        ClassLoaderTemplateResolver resolver 
+            = new ClassLoaderTemplateResolver();
+        resolver.setPrefix("templates/sessionattrs/");
+        resolver.setSuffix(".html");
+        resolver.setTemplateMode(TemplateMode.HTML);
+        resolver.setCharacterEncoding("UTF-8");
+        return resolver;
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/SessionAttrsApplication.java b/spring-5/src/main/java/com/baeldung/sessionattrs/SessionAttrsApplication.java
new file mode 100644
index 0000000000..7b9f8a700f
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/SessionAttrsApplication.java
@@ -0,0 +1,16 @@
+package com.baeldung.sessionattrs;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
+import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration;
+
+@SpringBootApplication(
+        exclude = {SecurityAutoConfiguration.class, 
+                DataSourceAutoConfiguration.class})
+public class SessionAttrsApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(SessionAttrsApplication.class, args);
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxy.java b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxy.java
new file mode 100644
index 0000000000..0c3bd6c8b6
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxy.java
@@ -0,0 +1,45 @@
+package com.baeldung.sessionattrs;
+
+import java.time.LocalDateTime;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller
+@RequestMapping("/scopedproxy")
+public class TodoControllerWithScopedProxy {
+
+    private TodoList todos;
+
+    public TodoControllerWithScopedProxy(TodoList todos) {
+        this.todos = todos;
+    }
+
+    @GetMapping("/form")
+    public String showForm(Model model) {
+        if (!todos.isEmpty()) {
+            model.addAttribute("todo", todos.peekLast());
+        } else {
+            model.addAttribute("todo", new TodoItem());
+        }
+
+        return "scopedproxyform";
+    }
+
+    @PostMapping("/form")
+    public String create(@ModelAttribute TodoItem todo) {
+        todo.setCreateDate(LocalDateTime.now());
+        todos.add(todo);
+        return "redirect:/scopedproxy/todos.html";
+    }
+
+    @GetMapping("/todos.html")
+    public String list(Model model) {
+        model.addAttribute("todos", todos);
+        return "scopedproxytodos";
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributes.java b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributes.java
new file mode 100644
index 0000000000..fc7e57b1db
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributes.java
@@ -0,0 +1,55 @@
+package com.baeldung.sessionattrs;
+
+import java.time.LocalDateTime;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.SessionAttributes;
+import org.springframework.web.servlet.mvc.support.RedirectAttributes;
+import org.springframework.web.servlet.view.RedirectView;
+
+@Controller
+@RequestMapping("/sessionattributes")
+@SessionAttributes("todos")
+public class TodoControllerWithSessionAttributes {
+
+    @GetMapping("/form")
+    public String showForm(
+            Model model,
+            @ModelAttribute("todos") TodoList todos) {
+        if (!todos.isEmpty()) {
+            model.addAttribute("todo", todos.peekLast());
+        } else {
+            model.addAttribute("todo", new TodoItem());
+        }
+        return "sessionattributesform";
+    }
+
+    @PostMapping("/form")
+    public RedirectView create(
+            @ModelAttribute TodoItem todo, 
+            @ModelAttribute("todos") TodoList todos, 
+            RedirectAttributes attributes) {
+        todo.setCreateDate(LocalDateTime.now());
+        todos.add(todo);
+        attributes.addFlashAttribute("todos", todos);
+        return new RedirectView("/sessionattributes/todos.html");
+    }
+
+    @GetMapping("/todos.html")
+    public String list(
+            Model model, 
+            @ModelAttribute("todos") TodoList todos) {
+        model.addAttribute("todos", todos);
+        return "sessionattributestodos";
+    }
+
+    @ModelAttribute("todos")
+    public TodoList todos() {
+        return new TodoList();
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/TodoItem.java b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoItem.java
new file mode 100644
index 0000000000..619d61d5f0
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoItem.java
@@ -0,0 +1,39 @@
+package com.baeldung.sessionattrs;
+
+import java.time.LocalDateTime;
+
+public class TodoItem {
+
+    private String description;
+    private LocalDateTime createDate;
+
+    public TodoItem(String description, LocalDateTime createDate) {
+        this.description = description;
+        this.createDate = createDate;
+    }
+
+    public TodoItem() {
+        // default no arg constructor
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    public LocalDateTime getCreateDate() {
+        return createDate;
+    }
+
+    public void setCreateDate(LocalDateTime createDate) {
+        this.createDate = createDate;
+    }
+
+    @Override
+    public String toString() {
+        return "TodoItem [description=" + description + ", createDate=" + createDate + "]";
+    }
+}
diff --git a/spring-5/src/main/java/com/baeldung/sessionattrs/TodoList.java b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoList.java
new file mode 100644
index 0000000000..cad7811da4
--- /dev/null
+++ b/spring-5/src/main/java/com/baeldung/sessionattrs/TodoList.java
@@ -0,0 +1,8 @@
+package com.baeldung.sessionattrs;
+
+import java.util.ArrayDeque;
+
+@SuppressWarnings("serial")
+public class TodoList extends ArrayDeque<TodoItem>{
+
+}
diff --git a/spring-5/src/main/resources/templates/sessionattrs/index.html b/spring-5/src/main/resources/templates/sessionattrs/index.html
new file mode 100644
index 0000000000..72427cd62b
--- /dev/null
+++ b/spring-5/src/main/resources/templates/sessionattrs/index.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Session Scope in Spring MVC</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" 
+            integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+    </head>
+    <body>
+    	<div class="container">
+    		<p>
+    			<h3>Session Scope in Spring MVC - Example</h3>
+    		</p>
+    	</div>
+        <div class="container">
+			<div class="row">
+				<div class="col">
+					<a href="/scopedproxy/form" class="btn btn-sm btn-primary btn-block float-right" role="button">Session Scoped Proxy Example</a></div>
+				<div class="col">
+					<a href="/sessionattributes/form" class="btn btn-sm btn-primary btn-block float-right" role="button">Session Attributes Example</a></div>
+			</div>
+        </div>
+    </body>
+</html>
\ No newline at end of file
diff --git a/spring-5/src/main/resources/templates/sessionattrs/scopedproxyform.html b/spring-5/src/main/resources/templates/sessionattrs/scopedproxyform.html
new file mode 100644
index 0000000000..e72651556b
--- /dev/null
+++ b/spring-5/src/main/resources/templates/sessionattrs/scopedproxyform.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Session Scope in Spring MVC</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+    </head>
+    <body>
+    	<div class="container">
+    		<p>
+    			<h3>Scoped Proxy Example</h3>
+    		</p>
+    	</div>
+        <div class="container">
+            <h5>Enter a TODO</h5>
+                <form action="#" th:action="@{/scopedproxy/form}" th:object="${todo}" method="post">
+                	<div class="input-group">
+                		<input type="text" th:field="*{description}" class="form-control" placeholder="TODO" required autofocus/>
+						<button class="btn btn-sm btn-primary form-control text-center" type="submit" style="max-width: 80px;">Create</button>
+                	</div>
+                </form>
+        </div>
+    </body>
+</html>
\ No newline at end of file
diff --git a/spring-5/src/main/resources/templates/sessionattrs/scopedproxytodos.html b/spring-5/src/main/resources/templates/sessionattrs/scopedproxytodos.html
new file mode 100644
index 0000000000..5493b5cf64
--- /dev/null
+++ b/spring-5/src/main/resources/templates/sessionattrs/scopedproxytodos.html
@@ -0,0 +1,48 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Session Scope in Spring MVC</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" 
+            rel="stylesheet" 
+            integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" 
+            crossorigin="anonymous">
+    </head>
+    <body>
+    	<div class="container">
+    		<p>
+    			<h3>Scoped Proxy Example</h3>
+    		</p>
+    	</div>
+        <div class="container">
+        	<br/>
+        	<div class="row">
+        				<a th:href="@{/scopedproxy/form}" class="btn btn-sm btn-primary btn-block" role="button" 
+										style="width: 10em;">Add New</a>
+        	</div>
+        	<br/>
+        	<div class="row">
+        		<div class="col card" style="padding: 1em;">
+       				<div class="card-block">
+       					<h5 class="card-title">TODO List</h5>
+						<table>
+							<tbody>
+								<tr>
+									<th width="75%">Description</th>
+									<th width="25%" >Create Date</th>
+								</tr>
+								<tr th:each="todo : ${todos}">
+									<td th:text="${todo.description}">Description</td>
+									<td th:text="${#temporals.format(todo.createDate, 'MM-dd-yyyy HH:mm:ss')}">Create Date</td>
+								</tr>
+							</tbody>
+						</table>
+					</div>
+				</div>
+			</div>
+        </div>
+    </body>
+</html>
\ No newline at end of file
diff --git a/spring-5/src/main/resources/templates/sessionattrs/sessionattributesform.html b/spring-5/src/main/resources/templates/sessionattrs/sessionattributesform.html
new file mode 100644
index 0000000000..28e1d5d2c1
--- /dev/null
+++ b/spring-5/src/main/resources/templates/sessionattrs/sessionattributesform.html
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Session Scope in Spring MVC</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+    </head>
+    <body>
+    	<div class="container">
+    		<p>
+    			<h3>Session Attributes Example</h3>
+    		</p>
+    	</div>
+        <div class="container">
+            <h5>Enter a TODO</h5>
+                <form action="#" th:action="@{/sessionattributes/form}" th:object="${todo}" method="post">
+                	<div class="input-group">
+                		<input type="text" th:field="*{description}" class="form-control" placeholder="TODO" required autofocus/>
+						<button class="btn btn-sm btn-primary form-control text-center" type="submit" style="max-width: 80px;">Create</button>
+                	</div>
+                </form>
+        </div>
+    </body>
+</html>
\ No newline at end of file
diff --git a/spring-5/src/main/resources/templates/sessionattrs/sessionattributestodos.html b/spring-5/src/main/resources/templates/sessionattrs/sessionattributestodos.html
new file mode 100644
index 0000000000..4bae12ffb9
--- /dev/null
+++ b/spring-5/src/main/resources/templates/sessionattrs/sessionattributestodos.html
@@ -0,0 +1,48 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Session Scope in Spring MVC</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" 
+            rel="stylesheet" 
+            integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" 
+            crossorigin="anonymous">
+    </head>
+    <body>
+    	<div class="container">
+    		<p>
+    			<h3>Session Attributes Example</h3>
+    		</p>
+    	</div>
+        <div class="container">
+        	<br/>
+        	<div class="row">
+        				<a th:href="@{/sessionattributes/form}" class="btn btn-sm btn-primary btn-block" role="button" 
+										style="width: 10em;">Add New</a>
+        	</div>
+        	<br/>
+        	<div class="row">
+        		<div class="col card" style="padding: 1em;">
+       				<div class="card-block">
+       					<h5 class="card-title">TODO List</h5>
+						<table>
+							<tbody>
+								<tr>
+									<th width="75%">Description</th>
+									<th width="25%" >Create Date</th>
+								</tr>
+								<tr th:each="todo : ${todos}">
+									<td th:text="${todo.description}">Description</td>
+									<td th:text="${#temporals.format(todo.createDate, 'MM-dd-yyyy HH:mm:ss')}">Create Date</td>
+								</tr>
+							</tbody>
+						</table>
+					</div>
+				</div>
+			</div>
+        </div>
+    </body>
+</html>
\ No newline at end of file
diff --git a/spring-5/src/test/java/com/baeldung/sessionattrs/SessionAttrsApplicationTests.java b/spring-5/src/test/java/com/baeldung/sessionattrs/SessionAttrsApplicationTests.java
new file mode 100644
index 0000000000..0b15a2114d
--- /dev/null
+++ b/spring-5/src/test/java/com/baeldung/sessionattrs/SessionAttrsApplicationTests.java
@@ -0,0 +1,16 @@
+package com.baeldung.sessionattrs;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class SessionAttrsApplicationTests {
+
+    @Test
+    public void contextLoads() {
+    }
+
+}
diff --git a/spring-5/src/test/java/com/baeldung/sessionattrs/TestConfig.java b/spring-5/src/test/java/com/baeldung/sessionattrs/TestConfig.java
new file mode 100644
index 0000000000..07d65dd7c2
--- /dev/null
+++ b/spring-5/src/test/java/com/baeldung/sessionattrs/TestConfig.java
@@ -0,0 +1,17 @@
+package com.baeldung.sessionattrs;
+
+import org.springframework.beans.factory.config.CustomScopeConfigurer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.support.SimpleThreadScope;
+
+@Configuration
+public class TestConfig {
+
+    @Bean
+    public CustomScopeConfigurer customScopeConfigurer() {
+        CustomScopeConfigurer configurer = new CustomScopeConfigurer();
+        configurer.addScope("session", new SimpleThreadScope());
+        return configurer;
+    }
+}
diff --git a/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxyTest.java b/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxyTest.java
new file mode 100644
index 0000000000..3db7c183ce
--- /dev/null
+++ b/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxyTest.java
@@ -0,0 +1,68 @@
+package com.baeldung.sessionattrs;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.model;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Import;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.util.StringUtils;
+import org.springframework.web.context.WebApplicationContext;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@AutoConfigureMockMvc
+@Import(TestConfig.class)
+public class TodoControllerWithScopedProxyTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private WebApplicationContext wac;
+
+    @Before
+    public void setup() {
+        this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac)
+            .build();   
+    }
+
+    @Test
+    public void whenFirstRequest_thenContainsAllCategoriesAndUnintializedTodo() throws Exception {
+        MvcResult result = mockMvc.perform(get("/scopedproxy/form"))
+            .andExpect(status().isOk())
+            .andExpect(model().attributeExists("todo"))
+            .andReturn();
+
+        TodoItem item = (TodoItem) result.getModelAndView().getModel().get("todo");
+        assertTrue(StringUtils.isEmpty(item.getDescription()));
+    }
+
+    @Test
+    public void whenSubmit_thenSubsequentFormRequestContainsMostRecentTodo() throws Exception {
+        mockMvc.perform(post("/scopedproxy/form")
+            .param("description", "newtodo"))
+            .andExpect(status().is3xxRedirection())
+            .andReturn();
+
+        MvcResult result = mockMvc.perform(get("/scopedproxy/form"))
+            .andExpect(status().isOk())
+            .andExpect(model().attributeExists("todo"))
+            .andReturn();
+        TodoItem item = (TodoItem) result.getModelAndView().getModel().get("todo");
+        assertEquals("newtodo", item.getDescription());
+    }
+
+}
diff --git a/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributesTest.java b/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributesTest.java
new file mode 100644
index 0000000000..a09fac9699
--- /dev/null
+++ b/spring-5/src/test/java/com/baeldung/sessionattrs/TodoControllerWithSessionAttributesTest.java
@@ -0,0 +1,68 @@
+package com.baeldung.sessionattrs;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.model;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.util.StringUtils;
+import org.springframework.web.context.WebApplicationContext;
+import org.springframework.web.servlet.FlashMap;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@AutoConfigureMockMvc
+public class TodoControllerWithSessionAttributesTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private WebApplicationContext wac;
+
+    @Before
+    public void setup() {
+        this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac)
+            .build();
+    }
+
+    @Test
+    public void whenFirstRequest_thenContainsUnintializedTodo() throws Exception {
+        MvcResult result = mockMvc.perform(get("/sessionattributes/form"))
+            .andExpect(status().isOk())
+            .andExpect(model().attributeExists("todo"))
+            .andReturn();
+
+        TodoItem item = (TodoItem) result.getModelAndView().getModel().get("todo");
+        assertTrue(StringUtils.isEmpty(item.getDescription()));
+    }
+
+    @Test
+    public void whenSubmit_thenSubsequentFormRequestContainsMostRecentTodo() throws Exception {
+        FlashMap flashMap = mockMvc.perform(post("/sessionattributes/form")
+            .param("description", "newtodo"))
+            .andExpect(status().is3xxRedirection())
+            .andReturn().getFlashMap();
+
+        MvcResult result = mockMvc.perform(get("/sessionattributes/form")
+            .sessionAttrs(flashMap))
+            .andExpect(status().isOk())
+            .andExpect(model().attributeExists("todo"))
+            .andReturn();
+        TodoItem item = (TodoItem) result.getModelAndView().getModel().get("todo");
+        assertEquals("newtodo", item.getDescription());
+    }
+
+}
diff --git a/spring-batch/pom.xml b/spring-batch/pom.xml
index f372ebd724..f72024d32b 100644
--- a/spring-batch/pom.xml
+++ b/spring-batch/pom.xml
@@ -18,9 +18,10 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <spring.version>4.3.4.RELEASE</spring.version>
-        <spring.batch.version>3.0.7.RELEASE</spring.batch.version>
+        <spring.version>5.0.3.RELEASE</spring.version>
+        <spring.batch.version>4.0.0.RELEASE</spring.batch.version>
         <sqlite.version>3.15.1</sqlite.version>
+        <opencsv.version>4.1</opencsv.version>
     </properties>
 
     <dependencies>
@@ -51,6 +52,16 @@
             <artifactId>spring-batch-core</artifactId>
             <version>${spring.batch.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.batch</groupId>
+            <artifactId>spring-batch-test</artifactId>
+            <version>${spring.batch.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.opencsv</groupId>
+            <artifactId>opencsv</artifactId>
+            <version>${opencsv.version}</version>
+        </dependency>
     </dependencies>
 
 </project>
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineProcessor.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineProcessor.java
new file mode 100644
index 0000000000..5b6cd9add3
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineProcessor.java
@@ -0,0 +1,36 @@
+package org.baeldung.taskletsvschunks.chunks;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.item.ItemProcessor;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoUnit;
+
+public class LineProcessor implements ItemProcessor<Line, Line>, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LineProcessor.class);
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        logger.debug("Line Processor initialized.");
+    }
+
+    @Override
+    public Line process(Line line) throws Exception {
+        long age = ChronoUnit.YEARS.between(line.getDob(), LocalDate.now());
+        logger.debug("Calculated age " + age + " for line " + line.toString());
+        line.setAge(age);
+        return line;
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        logger.debug("Line Processor ended.");
+        return ExitStatus.COMPLETED;
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineReader.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineReader.java
new file mode 100644
index 0000000000..5f6b6de218
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LineReader.java
@@ -0,0 +1,36 @@
+package org.baeldung.taskletsvschunks.chunks;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.baeldung.taskletsvschunks.utils.FileUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.item.ItemReader;
+
+public class LineReader implements ItemReader<Line>, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LineReader.class);
+    private FileUtils fu;
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        fu = new FileUtils("taskletsvschunks/input/tasklets-vs-chunks.csv");
+        logger.debug("Line Reader initialized.");
+    }
+
+    @Override
+    public Line read() throws Exception {
+        Line line = fu.readLine();
+        if (line != null) logger.debug("Read line: " + line.toString());
+        return line;
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        fu.closeReader();
+        logger.debug("Line Reader ended.");
+        return ExitStatus.COMPLETED;
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LinesWriter.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LinesWriter.java
new file mode 100644
index 0000000000..66f9103a56
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/chunks/LinesWriter.java
@@ -0,0 +1,39 @@
+package org.baeldung.taskletsvschunks.chunks;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.baeldung.taskletsvschunks.utils.FileUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.item.ItemWriter;
+
+import java.util.List;
+
+public class LinesWriter implements ItemWriter<Line>, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LinesWriter.class);
+    private FileUtils fu;
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        fu = new FileUtils("output.csv");
+        logger.debug("Line Writer initialized.");
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        fu.closeWriter();
+        logger.debug("Line Writer ended.");
+        return ExitStatus.COMPLETED;
+    }
+
+    @Override
+    public void write(List<? extends Line> lines) throws Exception {
+        for (Line line : lines) {
+            fu.writeLine(line);
+            logger.debug("Wrote line " + line.toString());
+        }
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/ChunksConfig.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/ChunksConfig.java
new file mode 100644
index 0000000000..601ffb7f27
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/ChunksConfig.java
@@ -0,0 +1,90 @@
+package org.baeldung.taskletsvschunks.config;
+
+import org.baeldung.taskletsvschunks.chunks.LineProcessor;
+import org.baeldung.taskletsvschunks.chunks.LineReader;
+import org.baeldung.taskletsvschunks.chunks.LinesWriter;
+import org.baeldung.taskletsvschunks.model.Line;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
+import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.batch.core.launch.support.SimpleJobLauncher;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean;
+import org.springframework.batch.item.ItemProcessor;
+import org.springframework.batch.item.ItemReader;
+import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.support.transaction.ResourcelessTransactionManager;
+import org.springframework.batch.test.JobLauncherTestUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.transaction.PlatformTransactionManager;
+
+@Configuration
+@EnableBatchProcessing
+public class ChunksConfig {
+
+    @Autowired private JobBuilderFactory jobs;
+
+    @Autowired private StepBuilderFactory steps;
+
+    @Bean
+    public JobLauncherTestUtils jobLauncherTestUtils() {
+        return new JobLauncherTestUtils();
+    }
+
+    @Bean
+    public JobRepository jobRepository() throws Exception {
+        MapJobRepositoryFactoryBean factory = new MapJobRepositoryFactoryBean();
+        factory.setTransactionManager(transactionManager());
+        return (JobRepository) factory.getObject();
+    }
+
+    @Bean
+    public PlatformTransactionManager transactionManager() {
+        return new ResourcelessTransactionManager();
+    }
+
+    @Bean
+    public JobLauncher jobLauncher() throws Exception {
+        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
+        jobLauncher.setJobRepository(jobRepository());
+        return jobLauncher;
+    }
+
+    @Bean
+    public ItemReader<Line> itemReader() {
+        return new LineReader();
+    }
+
+    @Bean
+    public ItemProcessor<Line, Line> itemProcessor() {
+        return new LineProcessor();
+    }
+
+    @Bean
+    public ItemWriter<Line> itemWriter() {
+        return new LinesWriter();
+    }
+
+    @Bean
+    protected Step processLines(ItemReader<Line> reader, ItemProcessor<Line, Line> processor, ItemWriter<Line> writer) {
+        return steps.get("processLines").<Line, Line> chunk(2)
+          .reader(reader)
+          .processor(processor)
+          .writer(writer)
+          .build();
+    }
+
+    @Bean
+    public Job job() {
+        return jobs
+          .get("chunksJob")
+          .start(processLines(itemReader(), itemProcessor(), itemWriter()))
+          .build();
+    }
+
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/TaskletsConfig.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/TaskletsConfig.java
new file mode 100644
index 0000000000..b9d06d2639
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/config/TaskletsConfig.java
@@ -0,0 +1,103 @@
+package org.baeldung.taskletsvschunks.config;
+
+import org.baeldung.taskletsvschunks.tasklets.LinesProcessor;
+import org.baeldung.taskletsvschunks.tasklets.LinesReader;
+import org.baeldung.taskletsvschunks.tasklets.LinesWriter;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
+import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.batch.core.launch.support.SimpleJobLauncher;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean;
+import org.springframework.batch.support.transaction.ResourcelessTransactionManager;
+import org.springframework.batch.test.JobLauncherTestUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.transaction.PlatformTransactionManager;
+
+@Configuration
+@EnableBatchProcessing
+public class TaskletsConfig {
+
+    @Autowired private JobBuilderFactory jobs;
+
+    @Autowired private StepBuilderFactory steps;
+
+    @Bean
+    public JobLauncherTestUtils jobLauncherTestUtils() {
+        return new JobLauncherTestUtils();
+    }
+
+    @Bean
+    public JobRepository jobRepository() throws Exception {
+        MapJobRepositoryFactoryBean factory = new MapJobRepositoryFactoryBean();
+        factory.setTransactionManager(transactionManager());
+        return (JobRepository) factory.getObject();
+    }
+
+    @Bean
+    public PlatformTransactionManager transactionManager() {
+        return new ResourcelessTransactionManager();
+    }
+
+    @Bean
+    public JobLauncher jobLauncher() throws Exception {
+        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
+        jobLauncher.setJobRepository(jobRepository());
+        return jobLauncher;
+    }
+
+    @Bean
+    public LinesReader linesReader() {
+        return new LinesReader();
+    }
+
+    @Bean
+    public LinesProcessor linesProcessor() {
+        return new LinesProcessor();
+    }
+
+    @Bean
+    public LinesWriter linesWriter() {
+        return new LinesWriter();
+    }
+
+    @Bean
+    protected Step readLines() {
+        return steps
+          .get("readLines")
+          .tasklet(linesReader())
+          .build();
+    }
+
+    @Bean
+    protected Step processLines() {
+        return steps
+          .get("processLines")
+          .tasklet(linesProcessor())
+          .build();
+    }
+
+    @Bean
+    protected Step writeLines() {
+        return steps
+          .get("writeLines")
+          .tasklet(linesWriter())
+          .build();
+    }
+
+    @Bean
+    public Job job() {
+        return jobs
+          .get("taskletsJob")
+          .start(readLines())
+          .next(processLines())
+          .next(writeLines())
+          .build();
+    }
+
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/model/Line.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/model/Line.java
new file mode 100644
index 0000000000..fee6fd31a6
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/model/Line.java
@@ -0,0 +1,55 @@
+package org.baeldung.taskletsvschunks.model;
+
+import java.io.Serializable;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+
+public class Line implements Serializable {
+
+    private String name;
+    private LocalDate dob;
+    private Long age;
+
+    public Line(String name, LocalDate dob) {
+        this.name = name;
+        this.dob = dob;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public LocalDate getDob() {
+        return dob;
+    }
+
+    public void setDob(LocalDate dob) {
+        this.dob = dob;
+    }
+
+    public Long getAge() {
+        return age;
+    }
+
+    public void setAge(Long age) {
+        this.age = age;
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("[");
+        sb.append(this.name);
+        sb.append(",");
+        sb.append(this.dob.format(DateTimeFormatter.ofPattern("MM/dd/yyyy")));
+        if (this.age != null) {
+            sb.append(",");
+            sb.append(this.age);
+        }
+        sb.append("]");
+        return sb.toString();
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesProcessor.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesProcessor.java
new file mode 100644
index 0000000000..ba7a3088d5
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesProcessor.java
@@ -0,0 +1,49 @@
+package org.baeldung.taskletsvschunks.tasklets;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepContribution;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.core.scope.context.ChunkContext;
+import org.springframework.batch.core.step.tasklet.Tasklet;
+import org.springframework.batch.item.ExecutionContext;
+import org.springframework.batch.repeat.RepeatStatus;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoUnit;
+import java.util.List;
+
+public class LinesProcessor implements Tasklet, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LinesProcessor.class);
+
+    private List<Line> lines;
+
+    @Override
+    public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext) throws Exception {
+        for (Line line : lines) {
+            long age = ChronoUnit.YEARS.between(line.getDob(), LocalDate.now());
+            logger.debug("Calculated age " + age + " for line " + line.toString());
+            line.setAge(age);
+        }
+        return RepeatStatus.FINISHED;
+    }
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        ExecutionContext executionContext = stepExecution
+          .getJobExecution()
+          .getExecutionContext();
+        this.lines = (List<Line>) executionContext.get("lines");
+        logger.debug("Lines Processor initialized.");
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        logger.debug("Lines Processor ended.");
+        return ExitStatus.COMPLETED;
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesReader.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesReader.java
new file mode 100644
index 0000000000..9905ee8f8a
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesReader.java
@@ -0,0 +1,53 @@
+package org.baeldung.taskletsvschunks.tasklets;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.baeldung.taskletsvschunks.utils.FileUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepContribution;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.core.scope.context.ChunkContext;
+import org.springframework.batch.core.step.tasklet.Tasklet;
+import org.springframework.batch.repeat.RepeatStatus;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class LinesReader implements Tasklet, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LinesReader.class);
+
+    private List<Line> lines;
+    private FileUtils fu;
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        lines = new ArrayList<Line>();
+        fu = new FileUtils("taskletsvschunks/input/tasklets-vs-chunks.csv");
+        logger.debug("Lines Reader initialized.");
+    }
+
+    @Override
+    public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext) throws Exception {
+        Line line = fu.readLine();
+        while (line != null) {
+            lines.add(line);
+            logger.debug("Read line: " + line.toString());
+            line = fu.readLine();
+        }
+        return RepeatStatus.FINISHED;
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        fu.closeReader();
+        stepExecution
+          .getJobExecution()
+          .getExecutionContext()
+          .put("lines", this.lines);
+        logger.debug("Lines Reader ended.");
+        return ExitStatus.COMPLETED;
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesWriter.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesWriter.java
new file mode 100644
index 0000000000..937288a890
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/tasklets/LinesWriter.java
@@ -0,0 +1,50 @@
+package org.baeldung.taskletsvschunks.tasklets;
+
+import org.baeldung.taskletsvschunks.model.Line;
+import org.baeldung.taskletsvschunks.utils.FileUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.StepContribution;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.core.scope.context.ChunkContext;
+import org.springframework.batch.core.step.tasklet.Tasklet;
+import org.springframework.batch.item.ExecutionContext;
+import org.springframework.batch.repeat.RepeatStatus;
+
+import java.util.List;
+
+public class LinesWriter implements Tasklet, StepExecutionListener {
+
+    private final Logger logger = LoggerFactory.getLogger(LinesWriter.class);
+
+    private List<Line> lines;
+    private FileUtils fu;
+
+    @Override
+    public void beforeStep(StepExecution stepExecution) {
+        ExecutionContext executionContext = stepExecution
+          .getJobExecution()
+          .getExecutionContext();
+        this.lines = (List<Line>) executionContext.get("lines");
+        fu = new FileUtils("output.csv");
+        logger.debug("Lines Writer initialized.");
+    }
+
+    @Override
+    public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext) throws Exception {
+        for (Line line : lines) {
+            fu.writeLine(line);
+            logger.debug("Wrote line " + line.toString());
+        }
+        return RepeatStatus.FINISHED;
+    }
+
+    @Override
+    public ExitStatus afterStep(StepExecution stepExecution) {
+        fu.closeWriter();
+        logger.debug("Lines Writer ended.");
+        return ExitStatus.COMPLETED;
+    }
+}
diff --git a/spring-batch/src/main/java/org/baeldung/taskletsvschunks/utils/FileUtils.java b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/utils/FileUtils.java
new file mode 100644
index 0000000000..df36d5c756
--- /dev/null
+++ b/spring-batch/src/main/java/org/baeldung/taskletsvschunks/utils/FileUtils.java
@@ -0,0 +1,95 @@
+package org.baeldung.taskletsvschunks.utils;
+
+import com.opencsv.CSVReader;
+import com.opencsv.CSVWriter;
+import org.baeldung.taskletsvschunks.model.Line;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+
+public class FileUtils {
+
+    private final Logger logger = LoggerFactory.getLogger(FileUtils.class);
+
+    private String fileName;
+    private CSVReader CSVReader;
+    private CSVWriter CSVWriter;
+    private FileReader fileReader;
+    private FileWriter fileWriter;
+    private File file;
+
+    public FileUtils(String fileName) {
+        this.fileName = fileName;
+    }
+
+    public Line readLine() {
+        try {
+            if (CSVReader == null) initReader();
+            String[] line = CSVReader.readNext();
+            if (line == null) return null;
+            return new Line(line[0], LocalDate.parse(line[1], DateTimeFormatter.ofPattern("MM/dd/yyyy")));
+        } catch (Exception e) {
+            logger.error("Error while reading line in file: " + this.fileName);
+            return null;
+        }
+    }
+
+    public void writeLine(Line line) {
+        try {
+            if (CSVWriter == null) initWriter();
+            String[] lineStr = new String[2];
+            lineStr[0] = line.getName();
+            lineStr[1] = line
+              .getAge()
+              .toString();
+            CSVWriter.writeNext(lineStr);
+        } catch (Exception e) {
+            logger.error("Error while writing line in file: " + this.fileName);
+        }
+    }
+
+    private void initReader() throws Exception {
+        ClassLoader classLoader = this
+          .getClass()
+          .getClassLoader();
+        if (file == null) file = new File(classLoader
+          .getResource(fileName)
+          .getFile());
+        if (fileReader == null) fileReader = new FileReader(file);
+        if (CSVReader == null) CSVReader = new CSVReader(fileReader);
+    }
+
+    private void initWriter() throws Exception {
+        if (file == null) {
+            file = new File(fileName);
+            file.createNewFile();
+        }
+        if (fileWriter == null) fileWriter = new FileWriter(file, true);
+        if (CSVWriter == null) CSVWriter = new CSVWriter(fileWriter);
+    }
+
+    public void closeWriter() {
+        try {
+            CSVWriter.close();
+            fileWriter.close();
+        } catch (IOException e) {
+            logger.error("Error while closing writer.");
+        }
+    }
+
+    public void closeReader() {
+        try {
+            CSVReader.close();
+            fileReader.close();
+        } catch (IOException e) {
+            logger.error("Error while closing reader.");
+        }
+    }
+
+}
diff --git a/spring-batch/src/main/resources/logback.xml b/spring-batch/src/main/resources/logback.xml
new file mode 100644
index 0000000000..b110d1c226
--- /dev/null
+++ b/spring-batch/src/main/resources/logback.xml
@@ -0,0 +1,20 @@
+<configuration>
+
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <layout class="ch.qos.logback.classic.PatternLayout">
+            <Pattern>
+                %d{yyyy-MM-dd HH:mm:ss} [%thread] %level %logger{35} - %msg%n
+            </Pattern>
+        </layout>
+    </appender>
+
+    <logger name="org.baeldung.taskletsvschunks" level="debug"
+            additivity="false">
+        <appender-ref ref="STDOUT" />
+    </logger>
+
+    <root level="error">
+        <appender-ref ref="STDOUT" />
+    </root>
+
+</configuration>
\ No newline at end of file
diff --git a/spring-batch/src/main/resources/taskletsvschunks/input/tasklets-vs-chunks.csv b/spring-batch/src/main/resources/taskletsvschunks/input/tasklets-vs-chunks.csv
new file mode 100644
index 0000000000..214bd3cb70
--- /dev/null
+++ b/spring-batch/src/main/resources/taskletsvschunks/input/tasklets-vs-chunks.csv
@@ -0,0 +1,6 @@
+Mae Hodges,10/22/1972
+Gary Potter,02/22/1953
+Betty Wise,02/17/1968
+Wayne Rose,04/06/1977
+Adam Caldwell,09/27/1995
+Lucille Phillips,05/14/1992
\ No newline at end of file
diff --git a/spring-batch/src/test/java/org/baeldung/taskletsvschunks/chunks/ChunksTest.java b/spring-batch/src/test/java/org/baeldung/taskletsvschunks/chunks/ChunksTest.java
new file mode 100644
index 0000000000..2a71970637
--- /dev/null
+++ b/spring-batch/src/test/java/org/baeldung/taskletsvschunks/chunks/ChunksTest.java
@@ -0,0 +1,25 @@
+package org.baeldung.taskletsvschunks.chunks;
+
+import org.baeldung.taskletsvschunks.config.ChunksConfig;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.test.JobLauncherTestUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes  = ChunksConfig.class)
+public class ChunksTest {
+
+    @Autowired private JobLauncherTestUtils jobLauncherTestUtils;
+
+    @Test
+    public void givenChunksJob_WhenJobEnds_ThenStatusCompleted() throws Exception {
+        JobExecution jobExecution = jobLauncherTestUtils.launchJob();
+        Assert.assertEquals(ExitStatus.COMPLETED, jobExecution.getExitStatus());
+    }
+}
\ No newline at end of file
diff --git a/spring-batch/src/test/java/org/baeldung/taskletsvschunks/tasklets/TaskletsTest.java b/spring-batch/src/test/java/org/baeldung/taskletsvschunks/tasklets/TaskletsTest.java
new file mode 100644
index 0000000000..20379b58fe
--- /dev/null
+++ b/spring-batch/src/test/java/org/baeldung/taskletsvschunks/tasklets/TaskletsTest.java
@@ -0,0 +1,25 @@
+package org.baeldung.taskletsvschunks.tasklets;
+
+import org.baeldung.taskletsvschunks.config.TaskletsConfig;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.batch.core.ExitStatus;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.test.JobLauncherTestUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = TaskletsConfig.class)
+public class TaskletsTest {
+
+    @Autowired private JobLauncherTestUtils jobLauncherTestUtils;
+
+    @Test
+    public void givenTaskletsJob_WhenJobEnds_ThenStatusCompleted() throws Exception {
+        JobExecution jobExecution = jobLauncherTestUtils.launchJob();
+        Assert.assertEquals(ExitStatus.COMPLETED, jobExecution.getExitStatus());
+    }
+}
\ No newline at end of file
diff --git a/spring-boot-bootstrap/pom.xml b/spring-boot-bootstrap/pom.xml
index 5ad8330a89..21c0ea60a8 100644
--- a/spring-boot-bootstrap/pom.xml
+++ b/spring-boot-bootstrap/pom.xml
@@ -24,12 +24,12 @@
             <dependency>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-starter-data-jpa</artifactId>
-                <version>1.5.5.RELEASE</version>
+                <version>1.5.10.RELEASE</version>
             </dependency>
             <dependency>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-dependencies</artifactId>
-                <version>1.5.6.RELEASE</version>
+                <version>1.5.10.RELEASE</version>
                 <type>pom</type>
                 <scope>import</scope>
             </dependency>
diff --git a/spring-boot-property-exp/pom.xml b/spring-boot-property-exp/pom.xml
index 0c54d57db1..1a1e31385e 100644
--- a/spring-boot-property-exp/pom.xml
+++ b/spring-boot-property-exp/pom.xml
@@ -1,6 +1,11 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <name>spring-boot-property-exp</name>
+
+    <groupId>com.baeldung</groupId>
+    <artifactId>spring-boot-property-exp</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <packaging>pom</packaging>
 
     <parent>
         <artifactId>parent-modules</artifactId>
@@ -8,17 +13,6 @@
         <version>1.0.0-SNAPSHOT</version>
     </parent>
 
-    <modelVersion>4.0.0</modelVersion>
-
-    <groupId>com.baeldung</groupId>
-    <artifactId>spring-boot-property-exp</artifactId>
-    <version>0.0.1-SNAPSHOT</version>
-
-    <packaging>pom</packaging>
-
-    <name>spring-boot-property-exp</name>
-    <url>http://maven.apache.org</url>
-
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
@@ -28,5 +22,4 @@
         <module>property-exp-custom-config</module>
     </modules>
 
-
 </project>
diff --git a/spring-boot-property-exp/property-exp-custom-config/pom.xml b/spring-boot-property-exp/property-exp-custom-config/pom.xml
index 7822b31cf2..019e2362a1 100644
--- a/spring-boot-property-exp/property-exp-custom-config/pom.xml
+++ b/spring-boot-property-exp/property-exp-custom-config/pom.xml
@@ -1,32 +1,26 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <parent>
-        <artifactId>spring-boot-property-exp</artifactId>
-        <groupId>com.baeldung</groupId>
-        <version>0.0.1-SNAPSHOT</version>
-    </parent>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
+    <name>property-exp-custom</name>
 
     <groupId>com.baeldung</groupId>
     <artifactId>property-exp-custom-config</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <packaging>jar</packaging>
 
-    <name>property-exp-custom</name>
-    <url>http://maven.apache.org</url>
-
-    <properties>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <custom.property>Custom Property Value</custom.property>
-    </properties>
+    <parent>
+        <artifactId>spring-boot-property-exp</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>0.0.1-SNAPSHOT</version>
+    </parent>
 
     <dependencies>
+
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter</artifactId>
-            <version>1.5.4.RELEASE</version>
+            <version>1.5.10.RELEASE</version>
         </dependency>
+
     </dependencies>
 
     <build>
@@ -73,5 +67,9 @@
         </plugins>
     </build>
 
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <custom.property>Custom Property Value</custom.property>
+    </properties>
 
 </project>
diff --git a/spring-boot-property-exp/property-exp-default-config/pom.xml b/spring-boot-property-exp/property-exp-default-config/pom.xml
index 0625916d32..5dc47d287d 100644
--- a/spring-boot-property-exp/property-exp-default-config/pom.xml
+++ b/spring-boot-property-exp/property-exp-default-config/pom.xml
@@ -1,27 +1,17 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
-    <parent>
-        <groupId>org.springframework.boot</groupId>
-        <artifactId>spring-boot-starter-parent</artifactId>
-        <version>1.5.4.RELEASE</version>
-    </parent>
-
+    <name>property-exp-default</name>
+    
     <groupId>com.baeldung</groupId>
     <artifactId>property-exp-default-config</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <packaging>jar</packaging>
 
-    <name>property-exp-default</name>
-    <url>http://maven.apache.org</url>
-
-    <properties>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <custom.property>Custom Property Value</custom.property>
-    </properties>
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>1.5.10.RELEASE</version>
+    </parent>
 
     <dependencies>
         <dependency>
@@ -42,4 +32,9 @@
         </plugins>
     </build>
 
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <custom.property>Custom Property Value</custom.property>
+    </properties>
+
 </project>
diff --git a/spring-cloud/pom.xml b/spring-cloud/pom.xml
index d94b334bc8..c093b87be3 100644
--- a/spring-cloud/pom.xml
+++ b/spring-cloud/pom.xml
@@ -21,7 +21,8 @@
         <module>spring-cloud-aws</module>
         <module>spring-cloud-consul</module>
         <module>spring-cloud-zuul-eureka-integration</module>
-	</modules>
+        <module>spring-cloud-contract</module>
+    </modules>
     <packaging>pom</packaging>
 
     <name>spring-cloud</name>
diff --git a/spring-cloud/spring-cloud-contract/pom.xml b/spring-cloud/spring-cloud-contract/pom.xml
new file mode 100644
index 0000000000..3981aae2ac
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/pom.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+    <modules>
+        <module>spring-cloud-contract-producer</module>
+        <module>spring-cloud-contract-consumer</module>
+    </modules>
+    <packaging>pom</packaging>
+
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <artifactId>spring-cloud-contract</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+
+    
+</project>
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/pom.xml b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/pom.xml
new file mode 100644
index 0000000000..67fea178eb
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/pom.xml
@@ -0,0 +1,68 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <artifactId>spring-cloud-contract-consumer</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+
+    <name>spring-cloud-contract-consumer</name>
+    <description>Spring Cloud Consumer Sample</description>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud-contract</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>..</relativePath>
+    </parent>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <java.version>1.8</java.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-contract-wiremock</artifactId>
+            <version>1.2.2.RELEASE</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-contract-stub-runner</artifactId>
+            <version>1.2.2.RELEASE</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>1.5.9.RELEASE</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-rest</artifactId>
+            <version>1.5.9.RELEASE</version>
+        </dependency>
+        <dependency>
+            <groupId>com.baeldung.spring.cloud</groupId>
+            <artifactId>spring-cloud-contract-producer</artifactId>
+            <version>1.0.0-SNAPSHOT</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+
+</project>
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/SpringCloudContractConsumerApplication.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/SpringCloudContractConsumerApplication.java
new file mode 100644
index 0000000000..7383ae5afa
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/SpringCloudContractConsumerApplication.java
@@ -0,0 +1,18 @@
+package com.baeldung.spring.cloud.springcloudcontractconsumer;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.web.client.RestTemplate;
+
+@SpringBootApplication
+public class SpringCloudContractConsumerApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(SpringCloudContractConsumerApplication.class, args);
+    }
+
+    @Bean
+    RestTemplate restTemplate() {
+        return new RestTemplate();
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathController.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathController.java
new file mode 100644
index 0000000000..58e6d5d5b8
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathController.java
@@ -0,0 +1,31 @@
+package com.baeldung.spring.cloud.springcloudcontractconsumer.controller;
+
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.*;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.client.RestTemplate;
+
+
+@RestController
+public class BasicMathController {
+
+    @Autowired
+    private RestTemplate restTemplate;
+
+    @GetMapping("/calculate")
+    public String checkOddAndEven(@RequestParam("number") Integer number) {
+        HttpHeaders httpHeaders = new HttpHeaders();
+        httpHeaders.add("Content-Type", "application/json");
+
+        ResponseEntity<String> responseEntity = restTemplate.exchange(
+          "http://localhost:8090/validate/prime-number?number=" + number,
+          HttpMethod.GET,
+          new HttpEntity<>(httpHeaders),
+          String.class);
+
+        return responseEntity.getBody();
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/resources/application.yml b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/main/resources/application.yml
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/test/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathControllerIntegrationTest.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/test/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathControllerIntegrationTest.java
new file mode 100644
index 0000000000..5cf5c6d3b8
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-consumer/src/test/java/com/baeldung/spring/cloud/springcloudcontractconsumer/controller/BasicMathControllerIntegrationTest.java
@@ -0,0 +1,44 @@
+package com.baeldung.spring.cloud.springcloudcontractconsumer.controller;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.json.AutoConfigureJsonTesters;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.cloud.contract.stubrunner.spring.AutoConfigureStubRunner;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
+
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
+@AutoConfigureMockMvc
+@AutoConfigureJsonTesters
+@AutoConfigureStubRunner(workOffline = true,
+        ids = "com.baeldung.spring.cloud:spring-cloud-contract-producer:+:stubs:8090")
+public class BasicMathControllerIntegrationTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Test
+    public void given_WhenPassEvenNumberInQueryParam_ThenReturnEven() throws Exception {
+        mockMvc.perform(MockMvcRequestBuilders.get("/calculate?number=2")
+          .contentType(MediaType.APPLICATION_JSON))
+          .andExpect(status().isOk())
+          .andExpect(content().string("Even"));
+    }
+
+    @Test
+    public void given_WhenPassOddNumberInQueryParam_ThenReturnOdd() throws Exception {
+        mockMvc.perform(MockMvcRequestBuilders.get("/calculate?number=1")
+          .contentType(MediaType.APPLICATION_JSON))
+          .andExpect(status().isOk())
+          .andExpect(content().string("Odd"));
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/pom.xml b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/pom.xml
new file mode 100644
index 0000000000..ac27dbb645
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/pom.xml
@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.baeldung.spring.cloud</groupId>
+    <artifactId>spring-cloud-contract-producer</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+
+    <name>spring-cloud-contract-producer</name>
+    <description>Spring Cloud Producer Sample</description>
+
+    <parent>
+        <groupId>com.baeldung.spring.cloud</groupId>
+        <artifactId>spring-cloud-contract</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>..</relativePath>
+    </parent>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <java.version>1.8</java.version>
+        <spring-cloud.version>Edgware.SR1</spring-cloud.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-starter-contract-verifier</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>1.5.9.RELEASE</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-rest</artifactId>
+            <version>1.5.9.RELEASE</version>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-contract-maven-plugin</artifactId>
+                <version>1.2.2.RELEASE</version>
+                <extensions>true</extensions>
+                <configuration>
+                    <baseClassForTests>com.baeldung.spring.cloud.springcloudcontractproducer.BaseTestClass
+                    </baseClassForTests>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework.cloud</groupId>
+                <artifactId>spring-cloud-dependencies</artifactId>
+                <version>${spring-cloud.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+
+</project>
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/SpringCloudContractProducerApplication.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/SpringCloudContractProducerApplication.java
new file mode 100644
index 0000000000..770c68c817
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/SpringCloudContractProducerApplication.java
@@ -0,0 +1,11 @@
+package com.baeldung.spring.cloud.springcloudcontractproducer;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class SpringCloudContractProducerApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(SpringCloudContractProducerApplication.class, args);
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/controller/EvenOddController.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/controller/EvenOddController.java
new file mode 100644
index 0000000000..b8cc002fb4
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/java/com/baeldung/spring/cloud/springcloudcontractproducer/controller/EvenOddController.java
@@ -0,0 +1,15 @@
+package com.baeldung.spring.cloud.springcloudcontractproducer.controller;
+
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class EvenOddController {
+
+    @GetMapping("/validate/prime-number")
+    public String isNumberPrime(@RequestParam("number") Integer number) {
+        return number % 2 == 0 ? "Even" : "Odd";
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/resources/application.properties b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/main/resources/application.properties
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/java/com/baeldung/spring/cloud/springcloudcontractproducer/BaseTestClass.java b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/java/com/baeldung/spring/cloud/springcloudcontractproducer/BaseTestClass.java
new file mode 100644
index 0000000000..253924b247
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/java/com/baeldung/spring/cloud/springcloudcontractproducer/BaseTestClass.java
@@ -0,0 +1,29 @@
+package com.baeldung.spring.cloud.springcloudcontractproducer;
+
+import com.baeldung.spring.cloud.springcloudcontractproducer.controller.EvenOddController;
+import io.restassured.module.mockmvc.RestAssuredMockMvc;
+import org.junit.Before;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.cloud.contract.verifier.messaging.boot.AutoConfigureMessageVerifier;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.test.web.servlet.setup.StandaloneMockMvcBuilder;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
+@DirtiesContext
+@AutoConfigureMessageVerifier
+public class BaseTestClass {
+
+    @Autowired
+    private EvenOddController evenOddController;
+
+    @Before
+    public void setup() {
+        StandaloneMockMvcBuilder standaloneMockMvcBuilder = MockMvcBuilders.standaloneSetup(evenOddController);
+        RestAssuredMockMvc.standaloneSetup(standaloneMockMvcBuilder);
+    }
+}
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnEvenWhenRequestParamIsEven.groovy b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnEvenWhenRequestParamIsEven.groovy
new file mode 100644
index 0000000000..78c36d7334
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnEvenWhenRequestParamIsEven.groovy
@@ -0,0 +1,17 @@
+import org.springframework.cloud.contract.spec.Contract
+
+Contract.make {
+    description "should return even when number input is even"
+    request {
+        method GET()
+        url("/validate/prime-number") {
+            queryParameters {
+                parameter("number", "2")
+            }
+        }
+    }
+    response {
+        body("Even")
+        status 200
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnOddWhenRequestParamIsOdd.groovy b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnOddWhenRequestParamIsOdd.groovy
new file mode 100644
index 0000000000..215f987bbf
--- /dev/null
+++ b/spring-cloud/spring-cloud-contract/spring-cloud-contract-producer/src/test/resources/contracts/shouldReturnOddWhenRequestParamIsOdd.groovy
@@ -0,0 +1,17 @@
+import org.springframework.cloud.contract.spec.Contract
+
+Contract.make {
+    description "should return odd when number input is odd"
+    request {
+        method GET()
+        url("/validate/prime-number") {
+            queryParameters {
+                parameter("number", "1")
+            }
+        }
+    }
+    response {
+        body("Odd")
+        status 200
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-gateway/gateway-service/pom.xml b/spring-cloud/spring-cloud-gateway/gateway-service/pom.xml
deleted file mode 100644
index 14cde4901a..0000000000
--- a/spring-cloud/spring-cloud-gateway/gateway-service/pom.xml
+++ /dev/null
@@ -1,79 +0,0 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-	<modelVersion>4.0.0</modelVersion>
-	
-	<artifactId>gateway-service</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
-
-    <name>Spring Cloud Gateway Service</name>
-    
-	<parent>
-        <groupId>com.baeldung.spring.cloud</groupId>
-        <artifactId>spring-cloud-gateway</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>..</relativePath>
-    </parent>
-
-	<properties>
-		<version>2.0.0.M2</version>
-	</properties>
-
-	<dependencies>
-		<dependency>
-			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-actuator</artifactId>
-			<version>${version}</version>
-		</dependency>
-		<dependency>
-			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-starter-webflux</artifactId>
-			<version>${version}</version>
-		</dependency>
-		<dependency>
-			<groupId>org.springframework.cloud</groupId>
-			<artifactId>spring-cloud-gateway-core</artifactId>
-			<version>${version}</version>
-		</dependency>
-		<dependency>
-			<groupId>org.springframework.cloud</groupId>
-			<artifactId>spring-cloud-starter-eureka</artifactId>
-			<version>${version}</version>
-		</dependency>
-		<dependency>
-			<groupId>org.hibernate</groupId>
-			<artifactId>hibernate-validator-cdi</artifactId>
-			<version>6.0.2.Final</version>
-		</dependency>
-		<dependency>
-			<groupId>javax.validation</groupId>
-			<artifactId>validation-api</artifactId>
-			<version>2.0.0.Final</version>
-		</dependency>
-		<dependency>
-			<groupId>io.projectreactor.ipc</groupId>
-			<artifactId>reactor-netty</artifactId>
-			<version>0.7.0.M1</version>
-		</dependency>
-	</dependencies>
-
-	<repositories>
-		<repository>
-			<id>spring-snapshots</id>
-			<name>Spring Snapshots</name>
-			<url>https://repo.spring.io/snapshot</url>
-			<snapshots>
-				<enabled>true</enabled>
-			</snapshots>
-		</repository>
-		<repository>
-			<id>spring-milestones</id>
-			<name>Spring Milestones</name>
-			<url>https://repo.spring.io/milestone</url>
-			<snapshots>
-				<enabled>false</enabled>
-			</snapshots>
-		</repository>
-	</repositories>
-
-</project>
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-gateway/pom.xml b/spring-cloud/spring-cloud-gateway/pom.xml
index 5142b25400..90737f369d 100644
--- a/spring-cloud/spring-cloud-gateway/pom.xml
+++ b/spring-cloud/spring-cloud-gateway/pom.xml
@@ -4,13 +4,8 @@
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
 
-    <groupId>com.baeldung.spring.cloud</groupId>
     <artifactId>spring-cloud-gateway</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
-    <modules>
-        <module>gateway-service</module>
-    </modules>
-    <packaging>pom</packaging>
+    <packaging>jar</packaging>
 
     <name>Spring Cloud Gateway</name>
 
@@ -25,7 +20,61 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven-compiler-plugin.version>3.7.0</maven-compiler-plugin.version>
         <spring-boot-maven-plugin.version>1.4.2.RELEASE</spring-boot-maven-plugin.version>
+        <version>2.0.0.M6</version>
     </properties>
+    
+    <dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-actuator</artifactId>
+			<version>${version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-webflux</artifactId>
+			<version>${version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-gateway-core</artifactId>
+			<version>${version}</version>
+		</dependency>
+	
+		<dependency>
+			<groupId>org.hibernate</groupId>
+			<artifactId>hibernate-validator-cdi</artifactId>
+			<version>6.0.2.Final</version>
+		</dependency>
+		<dependency>
+			<groupId>javax.validation</groupId>
+			<artifactId>validation-api</artifactId>
+			<version>2.0.0.Final</version>
+		</dependency>
+		<dependency>
+			<groupId>io.projectreactor.ipc</groupId>
+			<artifactId>reactor-netty</artifactId>
+			<version>0.7.0.M1</version>
+		</dependency>
+	</dependencies>
+	
+	<repositories>
+		<repository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</repository>
+		<repository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</repository>
+	</repositories>
 
     <build>
         <pluginManagement>
diff --git a/spring-cloud/spring-cloud-gateway/gateway-service/src/main/java/com/baeldung/spring/cloud/GatewayApplication.java b/spring-cloud/spring-cloud-gateway/src/main/java/com/baeldung/spring/cloud/GatewayApplication.java
similarity index 100%
rename from spring-cloud/spring-cloud-gateway/gateway-service/src/main/java/com/baeldung/spring/cloud/GatewayApplication.java
rename to spring-cloud/spring-cloud-gateway/src/main/java/com/baeldung/spring/cloud/GatewayApplication.java
diff --git a/spring-cloud/spring-cloud-gateway/gateway-service/src/main/resources/application.yml b/spring-cloud/spring-cloud-gateway/src/main/resources/application.yml
similarity index 100%
rename from spring-cloud/spring-cloud-gateway/gateway-service/src/main/resources/application.yml
rename to spring-cloud/spring-cloud-gateway/src/main/resources/application.yml
diff --git a/spring-cloud/spring-cloud-security/auth-client/src/main/java/com/baeldung/controller/CloudSiteController.java b/spring-cloud/spring-cloud-security/auth-client/src/main/java/com/baeldung/controller/CloudSiteController.java
index b6bfd0bcf6..c77a5e02c5 100644
--- a/spring-cloud/spring-cloud-security/auth-client/src/main/java/com/baeldung/controller/CloudSiteController.java
+++ b/spring-cloud/spring-cloud-security/auth-client/src/main/java/com/baeldung/controller/CloudSiteController.java
@@ -19,10 +19,10 @@ public class CloudSiteController {
         return "Hello From Baeldung!";
     }
 
-    @GetMapping("/person")
+    @GetMapping("/personInfo")
     public ModelAndView person() {
         ModelAndView mav = new ModelAndView("personinfo");
-        String personResourceUrl = "http://localhost:9000/personResource";
+        String personResourceUrl = "http://localhost:9000/person";
         mav.addObject("person", restOperations.getForObject(personResourceUrl, String.class));
         return mav;
     }
diff --git a/spring-cloud/spring-cloud-security/auth-client/src/main/resources/application.yml b/spring-cloud/spring-cloud-security/auth-client/src/main/resources/application.yml
index 06a950d270..2a758faeae 100644
--- a/spring-cloud/spring-cloud-security/auth-client/src/main/resources/application.yml
+++ b/spring-cloud/spring-cloud-security/auth-client/src/main/resources/application.yml
@@ -13,7 +13,7 @@ security:
       clientId: authserver
       clientSecret: passwordforauthserver
     resource:
-      userInfoUri: http://localhost:7070/authserver/user
+      userInfoUri: http://localhost:9000/user
 
 person:
   url: http://localhost:9000/person
@@ -27,7 +27,7 @@ zuul:
       url: http://localhost:9000
     user: 
       path: /user/**
-      url: http://localhost:7070/authserver/user
+      url: http://localhost:9000/user
 
 # Make sure the OAuth2 token is only relayed when using the internal API,
 # do not pass any authentication to the external API
diff --git a/spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/PersonInfoController.java b/spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/PersonInfoController.java
index 9e5420da5a..1958c0ebb8 100644
--- a/spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/PersonInfoController.java
+++ b/spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/PersonInfoController.java
@@ -10,9 +10,9 @@ import com.baeldung.model.Person;
 @RestController
 public class PersonInfoController {
 
-    @GetMapping("/personResource")
+    @GetMapping("/person")
     @PreAuthorize("hasAnyRole('ADMIN', 'USER')")
     public @ResponseBody Person personInfo() {
         return new Person("abir", "Dhaka", "Bangladesh", 29, "Male");
-    }
-}
\ No newline at end of file
+    }   
+}
diff --git a/spring-cloud/spring-cloud-security/auth-server/src/main/java/com/baeldung/controller/ResourceController.java b/spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/ResourceController.java
similarity index 100%
rename from spring-cloud/spring-cloud-security/auth-server/src/main/java/com/baeldung/controller/ResourceController.java
rename to spring-cloud/spring-cloud-security/auth-resource/src/main/java/com/baeldung/controller/ResourceController.java
diff --git a/spring-cloud/spring-cloud-security/auth-resource/src/main/resources/application.yml b/spring-cloud/spring-cloud-security/auth-resource/src/main/resources/application.yml
index 20a3313a60..52e02ba41b 100644
--- a/spring-cloud/spring-cloud-security/auth-resource/src/main/resources/application.yml
+++ b/spring-cloud/spring-cloud-security/auth-resource/src/main/resources/application.yml
@@ -8,7 +8,6 @@ security:
   sessions: NEVER
   oauth2:
     resource:
-      userInfoUri: http://localhost:7070/authserver/user
       jwt:
         keyValue: |
             -----BEGIN PUBLIC KEY-----
diff --git a/spring-cloud/spring-cloud-security/auth-server/src/main/java/com/baeldung/config/ResourceServerConfigurer.java b/spring-cloud/spring-cloud-security/auth-server/src/main/java/com/baeldung/config/ResourceServerConfigurer.java
deleted file mode 100644
index f97544dc59..0000000000
--- a/spring-cloud/spring-cloud-security/auth-server/src/main/java/com/baeldung/config/ResourceServerConfigurer.java
+++ /dev/null
@@ -1,21 +0,0 @@
-package com.baeldung.config;
-
-import org.springframework.context.annotation.Configuration;
-import org.springframework.security.config.annotation.web.builders.HttpSecurity;
-import org.springframework.security.oauth2.config.annotation.web.configuration.EnableResourceServer;
-import org.springframework.security.oauth2.config.annotation.web.configuration.ResourceServerConfigurerAdapter;
-
-/**
- * Our configuration for the OAuth2 User Info Resource Server.
- */
-@Configuration
-@EnableResourceServer
-public class ResourceServerConfigurer extends ResourceServerConfigurerAdapter {
-    @Override
-    public void configure(HttpSecurity http) throws Exception {
-        http.antMatcher("/user")
-                .authorizeRequests()
-                .anyRequest()
-                .authenticated();
-    }
-}
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/.gitignore b/spring-cloud/spring-cloud-task/springcloudtaskbatch/.gitignore
new file mode 100644
index 0000000000..f675857856
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/.gitignore
@@ -0,0 +1,2 @@
+/target/
+/.settings/
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/pom.xml b/spring-cloud/spring-cloud-task/springcloudtaskbatch/pom.xml
new file mode 100644
index 0000000000..4805f5296c
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/pom.xml
@@ -0,0 +1,81 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>org.baeldung.cloud</groupId>
+	<artifactId>springcloudtask</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>1.5.10.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+
+	<properties>
+		<start-class>com.baeldung.TaskDemo</start-class>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+		<java.version>1.8</java.version>
+		<spring-cloud-task.version>1.2.2.RELEASE</spring-cloud-task.version>
+	</properties>
+
+
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-task</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-task-core</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-batch</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-task-batch</artifactId>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-task-dependencies</artifactId>
+				<version>${spring-cloud-task.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/HelloWorldTaskConfigurer.java b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/HelloWorldTaskConfigurer.java
new file mode 100644
index 0000000000..dc2ba53138
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/HelloWorldTaskConfigurer.java
@@ -0,0 +1,14 @@
+package com.baeldung.task;
+
+import javax.sql.DataSource;
+
+import org.springframework.cloud.task.configuration.DefaultTaskConfigurer;
+
+public class HelloWorldTaskConfigurer
+    extends
+    DefaultTaskConfigurer {
+
+    public HelloWorldTaskConfigurer(DataSource dataSource) {
+        super(dataSource);
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/JobConfiguration.java b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/JobConfiguration.java
new file mode 100644
index 0000000000..6c215ad53d
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/JobConfiguration.java
@@ -0,0 +1,105 @@
+package com.baeldung.task;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.logging.Logger;
+
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.StepContribution;
+import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
+import org.springframework.batch.core.scope.context.ChunkContext;
+import org.springframework.batch.core.step.tasklet.Tasklet;
+import org.springframework.batch.item.ItemProcessor;
+import org.springframework.batch.item.ItemWriter;
+import org.springframework.batch.item.support.ListItemReader;
+import org.springframework.batch.repeat.RepeatStatus;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+public class JobConfiguration {
+
+    private final static Logger LOGGER = Logger
+        .getLogger(JobConfiguration.class.getName());
+
+    @Autowired
+    private JobBuilderFactory jobBuilderFactory;
+
+    @Autowired
+    private StepBuilderFactory stepBuilderFactory;
+
+    @Bean
+    public Step step1() {
+        return this.stepBuilderFactory.get("job1step1")
+            .tasklet(new Tasklet() {
+                @Override
+                public RepeatStatus execute(
+                    StepContribution contribution,
+                    ChunkContext chunkContext)
+                    throws Exception {
+                    LOGGER.info("Tasklet has run");
+                    return RepeatStatus.FINISHED;
+                }
+            }).build();
+    }
+
+    @Bean
+    public Step step2() {
+        return this.stepBuilderFactory
+            .get("job1step2")
+            .<String, String> chunk(3)
+            .reader(
+                new ListItemReader<>(Arrays.asList("7",
+                    "2", "3", "10", "5", "6")))
+            .processor(
+                new ItemProcessor<String, String>() {
+                    @Override
+                    public String process(String item)
+                        throws Exception {
+                        LOGGER.info("Processing of chunks");
+                        return String.valueOf(Integer
+                            .parseInt(item) * -1);
+                    }
+                })
+            .writer(new ItemWriter<String>() {
+                @Override
+                public void write(
+                    List<? extends String> items)
+                    throws Exception {
+                    for (String item : items) {
+                        LOGGER.info(">> " + item);
+                    }
+                }
+            }).build();
+    }
+
+    @Bean
+    public Job job1() {
+        return this.jobBuilderFactory.get("job1")
+            .start(step1())
+            .next(step2())
+            .build();
+    }
+
+    @Bean
+    public Job job2() {
+        return jobBuilderFactory.get("job2")
+            .start(stepBuilderFactory.get("job2step1")
+                .tasklet(new Tasklet() {
+                    @Override
+                    public RepeatStatus execute(
+                        StepContribution contribution,
+                        ChunkContext chunkContext)
+                        throws Exception {
+                        LOGGER
+                            .info("This job is from Baeldung");
+                        return RepeatStatus.FINISHED;
+                    }
+                })
+                .build())
+            .build();
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskDemo.java b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskDemo.java
new file mode 100644
index 0000000000..be2a173589
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskDemo.java
@@ -0,0 +1,56 @@
+package com.baeldung.task;
+
+import java.util.logging.Logger;
+
+import javax.sql.DataSource;
+
+import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.boot.ApplicationRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.task.configuration.EnableTask;
+import org.springframework.context.annotation.Bean;
+import org.springframework.stereotype.Component;
+
+@SpringBootApplication
+@EnableTask
+@EnableBatchProcessing
+public class TaskDemo {
+
+    private final static Logger LOGGER = Logger
+        .getLogger(TaskDemo.class.getName());
+
+    @Autowired
+    private DataSource dataSource;
+
+    @Bean
+    public HelloWorldTaskConfigurer getTaskConfigurer()
+    {
+        return new HelloWorldTaskConfigurer(dataSource);
+    }
+
+    @Bean
+    public TaskListener taskListener() {
+        return new TaskListener();
+    }
+
+    public static void main(String[] args) {
+        SpringApplication.run(TaskDemo.class, args);
+    }
+
+    @Component
+    public static class HelloWorldApplicationRunner
+        implements
+        ApplicationRunner {
+
+        @Override
+        public void run(ApplicationArguments arg0)
+            throws Exception {
+            // TODO Auto-generated method stub
+            LOGGER
+                .info("Hello World from Spring Cloud Task!");
+        }
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskListener.java b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskListener.java
new file mode 100644
index 0000000000..8250153b66
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/java/com/baeldung/task/TaskListener.java
@@ -0,0 +1,31 @@
+package com.baeldung.task;
+
+import java.util.logging.Logger;
+
+import org.springframework.cloud.task.listener.TaskExecutionListener;
+import org.springframework.cloud.task.repository.TaskExecution;
+
+public class TaskListener implements TaskExecutionListener {
+
+    private final static Logger LOGGER = Logger
+        .getLogger(TaskListener.class.getName());
+
+    @Override
+    public void onTaskEnd(TaskExecution arg0) {
+        // TODO Auto-generated method stub
+        LOGGER.info("End of Task");
+    }
+
+    @Override
+    public void onTaskFailed(TaskExecution arg0,
+        Throwable arg1) {
+        // TODO Auto-generated method stub
+
+    }
+
+    @Override
+    public void onTaskStartup(TaskExecution arg0) {
+        // TODO Auto-generated method stub
+        LOGGER.info("Task Startup");
+    }
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/resources/application.yml b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/resources/application.yml
new file mode 100644
index 0000000000..1187c12fe7
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtaskbatch/src/main/resources/application.yml
@@ -0,0 +1,26 @@
+logging:
+  level:
+    org:
+      springframework:
+        cloud:
+          task=DEBUG
+                           
+spring:
+  application:
+    name=helloWorld
+  datasource:
+    url: jdbc:mysql://localhost:3306/springcloud?useSSL=false
+    username: root
+    password:
+  jpa:
+    hibernate:
+      ddl-auto: create-drop
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.MySQL5Dialect
+  batch:
+    initialize-schema: always
+maven:
+  remoteRepositories:
+    springRepo:
+      url: https://repo.spring.io/libs-snapshot
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/.gitignore b/spring-cloud/spring-cloud-task/springcloudtasksink/.gitignore
new file mode 100644
index 0000000000..2af7cefb0a
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/.gitignore
@@ -0,0 +1,24 @@
+target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+nbproject/private/
+build/
+nbbuild/
+dist/
+nbdist/
+.nb-gradle/
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/pom.xml b/spring-cloud/spring-cloud-task/springcloudtasksink/pom.xml
new file mode 100644
index 0000000000..b717fffc7c
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/pom.xml
@@ -0,0 +1,88 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+
+	<groupId>com.baeldung</groupId>
+	<artifactId>SpringCloudTaskSink</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<packaging>jar</packaging>
+
+	<name>SpringCloudTaskSink</name>
+	<description>Demo project for Spring Boot</description>
+
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>1.5.10.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+		<java.version>1.8</java.version>
+		<spring-cloud-task.version>1.2.2.RELEASE</spring-cloud-task.version>
+		<spring-cloud.version>Edgware.SR2</spring-cloud.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-task</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-test-support</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-deployer-local</artifactId>
+			<version>1.3.0.RELEASE</version>
+		</dependency>
+	</dependencies>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-task-dependencies</artifactId>
+				<version>${spring-cloud-task.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-dependencies</artifactId>
+				<version>${spring-cloud.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+</project>
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplication.java b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplication.java
new file mode 100644
index 0000000000..62085e5fa5
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplication.java
@@ -0,0 +1,16 @@
+package com.baeldung.SpringCloudTaskFinal;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.task.launcher.annotation.EnableTaskLauncher;
+
+@SpringBootApplication
+@EnableTaskLauncher
+public class SpringCloudTaskSinkApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(
+            SpringCloudTaskSinkApplication.class, args);
+    }
+
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/TaskSinkConfiguration.java b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/TaskSinkConfiguration.java
new file mode 100644
index 0000000000..638de58ecb
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/java/com/baeldung/SpringCloudTaskFinal/TaskSinkConfiguration.java
@@ -0,0 +1,18 @@
+package com.baeldung.SpringCloudTaskFinal;
+
+import static org.mockito.Mockito.mock;
+
+import org.springframework.cloud.deployer.spi.task.TaskLauncher;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+
+@Configuration
+public class TaskSinkConfiguration {
+
+    @Bean
+    public TaskLauncher taskLauncher() {
+        return  mock(TaskLauncher.class);
+  }
+    
+}
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/resources/application.properties b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/resources/application.properties
new file mode 100644
index 0000000000..1660dc8516
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/src/main/resources/application.properties
@@ -0,0 +1 @@
+maven.remoteRepositories.springRepo.url=https://repo.spring.io/libs-snapshot
\ No newline at end of file
diff --git a/spring-cloud/spring-cloud-task/springcloudtasksink/src/test/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplicationTests.java b/spring-cloud/spring-cloud-task/springcloudtasksink/src/test/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplicationTests.java
new file mode 100644
index 0000000000..1f47eada14
--- /dev/null
+++ b/spring-cloud/spring-cloud-task/springcloudtasksink/src/test/java/com/baeldung/SpringCloudTaskFinal/SpringCloudTaskSinkApplicationTests.java
@@ -0,0 +1,72 @@
+package com.baeldung.SpringCloudTaskFinal;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.cloud.deployer.spi.core.AppDeploymentRequest;
+import org.springframework.cloud.deployer.spi.task.TaskLauncher;
+import org.springframework.cloud.stream.messaging.Sink;
+import org.springframework.cloud.task.launcher.TaskLaunchRequest;
+import org.springframework.context.ApplicationContext;
+import org.springframework.messaging.support.GenericMessage;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.verify;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(
+    classes = SpringCloudTaskSinkApplication.class)
+public class SpringCloudTaskSinkApplicationTests {
+
+    @Autowired
+    ApplicationContext context;
+
+    @Autowired
+    private Sink sink;
+
+    @Test
+    public void testTaskLaunch() throws IOException {
+
+        TaskLauncher taskLauncher =
+            context.getBean(TaskLauncher.class);
+
+        Map<String, String> prop = new HashMap<String, String>();
+        prop.put("server.port", "0");
+        TaskLaunchRequest request = new TaskLaunchRequest(
+            "maven://org.springframework.cloud.task.app:"
+                + "timestamp-task:jar:1.0.1.RELEASE", null,
+            prop,
+            null, null);
+        GenericMessage<TaskLaunchRequest> message = new GenericMessage<TaskLaunchRequest>(
+            request);
+        this.sink.input().send(message);
+
+        ArgumentCaptor<AppDeploymentRequest> deploymentRequest = ArgumentCaptor
+            .forClass(AppDeploymentRequest.class);
+
+        verify(taskLauncher).launch(
+            deploymentRequest.capture());
+
+        AppDeploymentRequest actualRequest = deploymentRequest
+            .getValue();
+
+        // Verifying the co-ordinate of launched Task here.
+        assertTrue(actualRequest.getCommandlineArguments()
+            .isEmpty());
+        assertEquals("0", actualRequest.getDefinition()
+            .getProperties().get("server.port"));
+        assertTrue(actualRequest
+            .getResource()
+            .toString()
+            .contains(
+                "org.springframework.cloud.task.app:timestamp-task:jar:1.0.1.RELEASE"));
+    }
+}
\ No newline at end of file
diff --git a/spring-dispatcher-servlet/src/main/java/com/baeldung/springdispatcherservlet/controller/MultipartController.java b/spring-dispatcher-servlet/src/main/java/com/baeldung/springdispatcherservlet/controller/MultipartController.java
index 1cc8261f7c..a693bf039f 100644
--- a/spring-dispatcher-servlet/src/main/java/com/baeldung/springdispatcherservlet/controller/MultipartController.java
+++ b/spring-dispatcher-servlet/src/main/java/com/baeldung/springdispatcherservlet/controller/MultipartController.java
@@ -25,14 +25,20 @@ public class MultipartController {
         try {
             InputStream in = file.getInputStream();
             String path = new File(".").getAbsolutePath();
-            FileOutputStream f = new FileOutputStream(path.substring(0, path.length()-1)+ "/uploads/" + file.getOriginalFilename());
-            int ch;
-            while ((ch = in.read()) != -1) {
-                f.write(ch);
+            FileOutputStream f = new FileOutputStream(path.substring(0, path.length() - 1) + "/uploads/" + file.getOriginalFilename());
+            try {
+                int ch;
+                while ((ch = in.read()) != -1) {
+                    f.write(ch);
+                }
+                modelAndView.getModel().put("message", "File uploaded successfully!");
+            } catch (Exception e) {
+                System.out.println("Exception uploading multipart: " + e);
+            } finally {
+                f.flush();
+                f.close();
+                in.close();
             }
-            f.flush();
-            f.close();
-            modelAndView.getModel().put("message", "File uploaded successfully!");
         } catch (Exception e) {
             System.out.println("Exception uploading multipart: " + e);
         }
diff --git a/spring-integration/pom.xml b/spring-integration/pom.xml
index 27cc7381e3..43e45dfd17 100644
--- a/spring-integration/pom.xml
+++ b/spring-integration/pom.xml
@@ -128,12 +128,6 @@
             <artifactId>spring-security-test</artifactId>
             <version>${spring.version}</version>
             <scope>test</scope>
-        </dependency>
-		<dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-test</artifactId>
-            <version>${spring.version}</version>
-            <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>junit</groupId>
diff --git a/spring-integration/src/test/resources/logback-test.xml b/spring-integration/src/test/resources/logback-test.xml
new file mode 100644
index 0000000000..a807be0ca2
--- /dev/null
+++ b/spring-integration/src/test/resources/logback-test.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <include resource="org/springframework/boot/logging/logback/base.xml" />
+	<logger name="org.springframework" level="ERROR"/>
+</configuration>
\ No newline at end of file
diff --git a/spring-jinq/README.md b/spring-jinq/README.md
new file mode 100644
index 0000000000..10d7903f49
--- /dev/null
+++ b/spring-jinq/README.md
@@ -0,0 +1,4 @@
+## Relevant articles:
+
+- [Introduction to Jinq with Spring](http://www.baeldung.com/spring-jinq)
+
diff --git a/spring-mvc-kotlin/pom.xml b/spring-mvc-kotlin/pom.xml
index 2d1dac5e29..28a5681c03 100644
--- a/spring-mvc-kotlin/pom.xml
+++ b/spring-mvc-kotlin/pom.xml
@@ -17,38 +17,64 @@
 
     <packaging>war</packaging>
 
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <hibernate.version>5.2.13.Final</hibernate.version>
+        <kotlin.version>1.2.21</kotlin.version>
+        <spring.version>4.3.10.RELEASE</spring.version>
+        <thymeleaf.version>3.0.7.RELEASE</thymeleaf.version>
+        <h2.version>1.4.196</h2.version>
+    </properties>
+
     <dependencies>
         <dependency>
             <groupId>org.jetbrains.kotlin</groupId>
-            <artifactId>kotlin-stdlib-jre8</artifactId>
-            <version>1.1.4</version>
+            <artifactId>kotlin-stdlib-jdk8</artifactId>
+            <version>${kotlin.version}</version>
         </dependency>
 
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-web</artifactId>
-            <version>4.3.10.RELEASE</version>
+            <version>${spring.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-webmvc</artifactId>
-            <version>4.3.10.RELEASE</version>
+            <version>${spring.version}</version>
         </dependency>
         <dependency>
             <groupId>org.thymeleaf</groupId>
             <artifactId>thymeleaf</artifactId>
-            <version>3.0.7.RELEASE</version>
+            <version>${thymeleaf.version}</version>
         </dependency>
 
         <dependency>
             <groupId>org.thymeleaf</groupId>
             <artifactId>thymeleaf-spring4</artifactId>
-            <version>3.0.7.RELEASE</version>
+            <version>${thymeleaf.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-testing</artifactId>
+            <version>${hibernate.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>${h2.version}</version>
+            <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>
-            <version>4.3.10.RELEASE</version>
+            <version>${spring.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -60,10 +86,11 @@
             <plugin>
                 <artifactId>kotlin-maven-plugin</artifactId>
                 <groupId>org.jetbrains.kotlin</groupId>
-                <version>1.1.4</version>
+                <version>${kotlin.version}</version>
                 <configuration>
                     <compilerPlugins>
                         <plugin>spring</plugin>
+                        <plugin>jpa</plugin>
                     </compilerPlugins>
                     <jvmTarget>1.8</jvmTarget>
                 </configuration>
@@ -87,7 +114,12 @@
                     <dependency>
                         <groupId>org.jetbrains.kotlin</groupId>
                         <artifactId>kotlin-maven-allopen</artifactId>
-                        <version>1.1.4-3</version>
+                        <version>${kotlin.version}</version>
+                    </dependency>
+                    <dependency>
+                        <groupId>org.jetbrains.kotlin</groupId>
+                        <artifactId>kotlin-maven-noarg</artifactId>
+                        <version>${kotlin.version}</version>
                     </dependency>
                 </dependencies>
             </plugin>
diff --git a/spring-mvc-kotlin/src/main/kotlin/com/baeldung/kotlin/jpa/Person.kt b/spring-mvc-kotlin/src/main/kotlin/com/baeldung/kotlin/jpa/Person.kt
new file mode 100644
index 0000000000..801bd1b0a5
--- /dev/null
+++ b/spring-mvc-kotlin/src/main/kotlin/com/baeldung/kotlin/jpa/Person.kt
@@ -0,0 +1,15 @@
+package com.baeldung.jpa
+
+import javax.persistence.Entity
+import javax.persistence.GeneratedValue
+import javax.persistence.GenerationType
+import javax.persistence.Id
+import javax.persistence.Table
+
+@Entity
+@Table(name = "person")
+data class Person(
+        @Id
+        @GeneratedValue(strategy = GenerationType.AUTO)
+        val id: Int,
+        val name: String)
\ No newline at end of file
diff --git a/spring-mvc-kotlin/src/test/kotlin/com/baeldung/kotlin/jpa/HibernateKotlinIntegrationTest.kt b/spring-mvc-kotlin/src/test/kotlin/com/baeldung/kotlin/jpa/HibernateKotlinIntegrationTest.kt
new file mode 100644
index 0000000000..8f54373406
--- /dev/null
+++ b/spring-mvc-kotlin/src/test/kotlin/com/baeldung/kotlin/jpa/HibernateKotlinIntegrationTest.kt
@@ -0,0 +1,44 @@
+package com.baeldung.kotlin.jpa
+
+import com.baeldung.jpa.Person
+import org.hibernate.cfg.Configuration
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase
+import org.hibernate.testing.transaction.TransactionUtil.doInHibernate
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import java.io.IOException
+import java.util.*
+
+
+class HibernateKotlinIntegrationTest : BaseCoreFunctionalTestCase() {
+
+    private val properties: Properties
+        @Throws(IOException::class)
+        get() {
+            val properties = Properties()
+            properties.load(javaClass.classLoader.getResourceAsStream("hibernate.properties"))
+            return properties
+        }
+
+    override fun getAnnotatedClasses(): Array<Class<*>> {
+        return arrayOf(Person::class.java)
+    }
+
+    override fun configure(configuration: Configuration) {
+        super.configure(configuration)
+        configuration.properties = properties
+    }
+
+    @Test
+    fun givenPerson_whenSaved_thenFound() {
+        val personToSave = Person(0, "John")
+        doInHibernate(({ this.sessionFactory() }), { session ->
+            session.persist(personToSave)
+            assertTrue(session.contains(personToSave))
+        })
+        doInHibernate(({ this.sessionFactory() }), { session ->
+            val personFound = session.find(Person::class.java, personToSave.id)
+            assertTrue(personToSave == personFound)
+        })
+    }
+}
\ No newline at end of file
diff --git a/spring-mvc-kotlin/src/test/resources/hibernate.properties b/spring-mvc-kotlin/src/test/resources/hibernate.properties
new file mode 100644
index 0000000000..7b8764637b
--- /dev/null
+++ b/spring-mvc-kotlin/src/test/resources/hibernate.properties
@@ -0,0 +1,9 @@
+hibernate.connection.driver_class=org.h2.Driver
+hibernate.connection.url=jdbc:h2:mem:mydb1;DB_CLOSE_DELAY=-1
+hibernate.connection.username=sa
+hibernate.connection.autocommit=true
+jdbc.password=
+
+hibernate.dialect=org.hibernate.dialect.H2Dialect
+hibernate.show_sql=true
+hibernate.hbm2ddl.auto=create-drop
\ No newline at end of file
diff --git a/spring-mvc-simple/pom.xml b/spring-mvc-simple/pom.xml
index 595e58f5f3..c0e4b63897 100644
--- a/spring-mvc-simple/pom.xml
+++ b/spring-mvc-simple/pom.xml
@@ -31,9 +31,17 @@
         <junit.jupiter.version>5.0.2</junit.jupiter.version>
         <junit.platform.version>1.0.2</junit.platform.version>
         <rome.version>1.9.0</rome.version>
+        <jackson.version>2.9.4</jackson.version>
+        <xstream.version>1.4.9</xstream.version>
+        <scribejava.version>5.1.0</scribejava.version>
     </properties>
 
     <dependencies>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-oxm</artifactId>
+            <version>5.0.2.RELEASE</version>
+        </dependency>
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>javax.servlet-api</artifactId>
@@ -121,6 +129,28 @@
             <artifactId>rome</artifactId>
             <version>${rome.version}</version>
         </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.dataformat</groupId>
+            <artifactId>jackson-dataformat-xml</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.thoughtworks.xstream</groupId>
+            <artifactId>xstream</artifactId>
+            <version>${xstream.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.github.scribejava</groupId>
+            <artifactId>scribejava-apis</artifactId>
+            <version>${scribejava.version}</version>
+        </dependency>
     </dependencies>
     <build>
         <pluginManagement>
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/configuration/ApplicationConfiguration.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/configuration/ApplicationConfiguration.java
index 69c45d90b3..3275d919ea 100644
--- a/spring-mvc-simple/src/main/java/com/baeldung/spring/configuration/ApplicationConfiguration.java
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/configuration/ApplicationConfiguration.java
@@ -1,26 +1,34 @@
 package com.baeldung.spring.configuration;
 
 import com.baeldung.spring.controller.rss.ArticleRssFeedViewResolver;
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import com.fasterxml.jackson.dataformat.xml.ser.ToXmlGenerator;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.StringHttpMessageConverter;
+import org.springframework.http.converter.feed.RssChannelHttpMessageConverter;
+import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+import org.springframework.http.converter.xml.MappingJackson2XmlHttpMessageConverter;
+import org.springframework.web.accept.ContentNegotiationManager;
 import org.springframework.web.multipart.MultipartResolver;
 import org.springframework.web.multipart.commons.CommonsMultipartResolver;
 import org.springframework.web.servlet.ViewResolver;
 import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
-import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;
 import org.springframework.web.servlet.view.InternalResourceViewResolver;
-import org.springframework.web.accept.ContentNegotiationManager;
 
-import java.util.List;
 import java.util.ArrayList;
+import java.util.List;
 
 @Configuration
 @EnableWebMvc
 @ComponentScan(basePackages = { "com.baeldung.springmvcforms", "com.baeldung.spring.controller", "com.baeldung.spring.validator" })
-class ApplicationConfiguration implements WebMvcConfigurer {
+class ApplicationConfiguration extends WebMvcConfigurerAdapter {
 
     @Override
     public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
@@ -49,4 +57,20 @@ class ApplicationConfiguration implements WebMvcConfigurer {
         multipartResolver.setMaxUploadSize(5242880);
         return multipartResolver;
     }
+
+    @Override
+    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
+        Jackson2ObjectMapperBuilder builder = Jackson2ObjectMapperBuilder.xml();
+        builder.indentOutput(true);
+
+        XmlMapper xmlMapper = builder.createXmlMapper(true).build();
+        xmlMapper.configure(ToXmlGenerator.Feature.WRITE_XML_DECLARATION, true);
+
+        converters.add(new StringHttpMessageConverter());
+        converters.add(new RssChannelHttpMessageConverter());
+        converters.add(new MappingJackson2HttpMessageConverter());
+        converters.add(new MappingJackson2XmlHttpMessageConverter(xmlMapper));
+
+        super.configureMessageConverters(converters);
+    }
 }
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleFeed.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleFeed.java
new file mode 100644
index 0000000000..71b225bf3f
--- /dev/null
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleFeed.java
@@ -0,0 +1,29 @@
+package com.baeldung.spring.controller.rss;
+
+import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlProperty;
+import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlElementWrapper;
+import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlRootElement;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+@JacksonXmlRootElement(localName="articles")
+public class ArticleFeed extends RssData implements Serializable {
+
+    @JacksonXmlProperty(localName = "item")
+    @JacksonXmlElementWrapper(useWrapping = false)
+    private List<ArticleItem> items = new ArrayList<ArticleItem>();
+
+    public void addItem(ArticleItem articleItem) {
+        this.items.add(articleItem);
+    }
+
+    public List<ArticleItem> getItems() {
+        return items;
+    }
+
+    public void setItems(List<ArticleItem> items) {
+        this.items = items;
+    }
+}
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleItem.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleItem.java
new file mode 100644
index 0000000000..6c91819676
--- /dev/null
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleItem.java
@@ -0,0 +1,22 @@
+package com.baeldung.spring.controller.rss;
+
+import java.io.Serializable;
+
+public class ArticleItem extends RssData implements Serializable {
+    private String author;
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    @Override
+    public String toString() {
+        return "ArticleItem{" +
+                "author='" + author + '\'' +
+                '}';
+    }
+}
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleRssController.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleRssController.java
index 8f23076e8e..b0cce99d33 100644
--- a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleRssController.java
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/ArticleRssController.java
@@ -1,59 +1,46 @@
 package com.baeldung.spring.controller.rss;
 
-import com.rometools.rome.feed.synd.*;
-import com.rometools.rome.io.FeedException;
-import com.rometools.rome.io.SyndFeedOutput;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.ResponseBody;
 
-import java.util.ArrayList;
 import java.util.Date;
-import java.util.List;
 
 @Controller
 public class ArticleRssController {
 
-    @GetMapping(value = "/rssMvc")
+    @GetMapping(value = "/rss1")
     public String articleMvcFeed() {
         return "articleFeedView";
     }
 
-    @GetMapping(value = "/rssRest", produces = "application/rss+xml")
+    @GetMapping(value = "/rss2")
     @ResponseBody
-    public String articleRestFeed() throws FeedException {
-        SyndFeed feed = new SyndFeedImpl();
-        feed.setFeedType("rss_2.0");
+    public ArticleFeed articleRestFeed2() {
+        ArticleFeed feed = new ArticleFeed();
         feed.setLink("http://localhost:8080/spring-mvc-simple/rss");
         feed.setTitle("Article Feed");
         feed.setDescription("Article Feed Description");
         feed.setPublishedDate(new Date());
 
-        List list = new ArrayList<SyndEntry>();
-
-        SyndEntry item1 = new SyndEntryImpl();
+        ArticleItem item1 = new ArticleItem();
         item1.setLink("http://www.baeldung.com/netty-exception-handling");
         item1.setTitle("Exceptions in Netty");
-        SyndContent description1 = new SyndContentImpl();
-        description1.setValue("In this quick article, we’ll be looking at exception handling in Netty.");
-        item1.setDescription(description1);
+        item1.setDescription("In this quick article, we’ll be looking at exception handling in Netty.");
         item1.setPublishedDate(new Date());
         item1.setAuthor("Carlos");
 
-        SyndEntry item2 = new SyndEntryImpl();
+        ArticleItem item2 = new ArticleItem();
         item2.setLink("http://www.baeldung.com/cockroachdb-java");
         item2.setTitle("Guide to CockroachDB in Java");
-        SyndContent description2 = new SyndContentImpl();
-        description2.setValue("This tutorial is an introductory guide to using CockroachDB with Java.");
-        item2.setDescription(description2);
+        item2.setDescription("This tutorial is an introductory guide to using CockroachDB with Java.");
         item2.setPublishedDate(new Date());
         item2.setAuthor("Baeldung");
 
-        list.add(item1);
-        list.add(item2);
-        feed.setEntries(list);
+        feed.addItem(item1);
+        feed.addItem(item2);
 
-        return new SyndFeedOutput().outputString(feed);
+        return feed;
     }
 
 }
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/RssData.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/RssData.java
new file mode 100644
index 0000000000..258712eb2d
--- /dev/null
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/rss/RssData.java
@@ -0,0 +1,56 @@
+package com.baeldung.spring.controller.rss;
+
+import java.io.Serializable;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+public class RssData implements Serializable {
+    private String link;
+    private String title;
+    private String description;
+    private String publishedDate;
+
+    public String getLink() {
+        return link;
+    }
+
+    public void setLink(String link) {
+        this.link = link;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    public String getPublishedDate() {
+        return publishedDate;
+    }
+
+    public void setPublishedDate(Date publishedDate) {
+        DateFormat df = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
+        this.publishedDate = df.format(publishedDate);
+    }
+
+    @Override
+    public String toString() {
+        return "RssData{" +
+                "link='" + link + '\'' +
+                ", title='" + title + '\'' +
+                ", description='" + description + '\'' +
+                ", publishedDate=" + publishedDate +
+                '}';
+    }
+}
diff --git a/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/scribe/ScribeController.java b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/scribe/ScribeController.java
new file mode 100644
index 0000000000..c5c97ff009
--- /dev/null
+++ b/spring-mvc-simple/src/main/java/com/baeldung/spring/controller/scribe/ScribeController.java
@@ -0,0 +1,55 @@
+package com.baeldung.spring.controller.scribe;
+
+import com.github.scribejava.apis.TwitterApi;
+import com.github.scribejava.core.builder.ServiceBuilder;
+import com.github.scribejava.core.model.*;
+import com.github.scribejava.core.oauth.OAuth10aService;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.servlet.view.RedirectView;
+
+import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
+import java.util.concurrent.ExecutionException;
+
+@Controller
+@RequestMapping("twitter")
+public class ScribeController {
+
+    private OAuth10aService createTwitterService() {
+        return new ServiceBuilder("PSRszoHhRDVhyo2RIkThEbWko")
+                .apiSecret("prpJbz03DcGRN46sb4ucdSYtVxG8unUKhcnu3an5ItXbEOuenL")
+                .callback("http://localhost:8080/spring-mvc-simple/twitter/callback")
+                .build(TwitterApi.instance());
+    }
+
+    @GetMapping(value = "/authorization")
+    public RedirectView authorization(HttpServletRequest servletReq) throws InterruptedException, ExecutionException, IOException {
+        OAuth10aService twitterService = createTwitterService();
+
+        OAuth1RequestToken requestToken = twitterService.getRequestToken();
+        String authorizationUrl = twitterService.getAuthorizationUrl(requestToken);
+        servletReq.getSession().setAttribute("requestToken", requestToken);
+
+        RedirectView redirectView = new RedirectView();
+        redirectView.setUrl(authorizationUrl);
+        return redirectView;
+    }
+
+    @GetMapping(value = "/callback", produces = "text/plain")
+    @ResponseBody
+    public String callback(HttpServletRequest servletReq, @RequestParam("oauth_verifier") String oauthV) throws InterruptedException, ExecutionException, IOException {
+        OAuth10aService twitterService = createTwitterService();
+        OAuth1RequestToken requestToken = (OAuth1RequestToken) servletReq.getSession().getAttribute("requestToken");
+        OAuth1AccessToken accessToken = twitterService.getAccessToken(requestToken, oauthV);
+
+        OAuthRequest request = new OAuthRequest(Verb.GET, "https://api.twitter.com/1.1/account/verify_credentials.json");
+        twitterService.signRequest(accessToken, request);
+        Response response = twitterService.execute(request);
+
+        return response.getBody();
+    }
+}
diff --git a/spring-security-openid/pom.xml b/spring-security-openid/pom.xml
index 4c8112a163..aeabb161c9 100644
--- a/spring-security-openid/pom.xml
+++ b/spring-security-openid/pom.xml
@@ -46,6 +46,11 @@
             <version>1.0.9.RELEASE</version>
         </dependency>
         
+        <dependency>
+            <groupId>com.auth0</groupId>
+            <artifactId>jwks-rsa</artifactId>
+            <version>0.3.0</version>
+        </dependency>
     </dependencies>
 
     <repositories>
diff --git a/spring-security-openid/src/main/java/org/baeldung/security/OpenIdConnectFilter.java b/spring-security-openid/src/main/java/org/baeldung/security/OpenIdConnectFilter.java
index c0970ab3cf..f12169cb27 100644
--- a/spring-security-openid/src/main/java/org/baeldung/security/OpenIdConnectFilter.java
+++ b/spring-security-openid/src/main/java/org/baeldung/security/OpenIdConnectFilter.java
@@ -1,12 +1,16 @@
 package org.baeldung.security;
 
 import java.io.IOException;
+import java.net.URL;
+import java.security.interfaces.RSAPublicKey;
+import java.util.Date;
 import java.util.Map;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.BadCredentialsException;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
@@ -14,16 +18,28 @@ import org.springframework.security.core.Authentication;
 import org.springframework.security.core.AuthenticationException;
 import org.springframework.security.jwt.Jwt;
 import org.springframework.security.jwt.JwtHelper;
+import org.springframework.security.jwt.crypto.sign.RsaVerifier;
 import org.springframework.security.oauth2.client.OAuth2RestOperations;
 import org.springframework.security.oauth2.client.OAuth2RestTemplate;
 import org.springframework.security.oauth2.common.OAuth2AccessToken;
-import org.springframework.security.oauth2.common.exceptions.InvalidTokenException;
 import org.springframework.security.oauth2.common.exceptions.OAuth2Exception;
 import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
 
+import com.auth0.jwk.Jwk;
+import com.auth0.jwk.JwkProvider;
+import com.auth0.jwk.UrlJwkProvider;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 public class OpenIdConnectFilter extends AbstractAuthenticationProcessingFilter {
+    @Value("${google.clientId}")
+    private String clientId;
+
+    @Value("${google.issuer}")
+    private String issuer;
+
+    @Value("${google.jwkUrl}")
+    private String jwkUrl;
+
     public OAuth2RestOperations restTemplate;
 
     public OpenIdConnectFilter(String defaultFilterProcessesUrl) {
@@ -42,19 +58,35 @@ public class OpenIdConnectFilter extends AbstractAuthenticationProcessingFilter
         }
         try {
             final String idToken = accessToken.getAdditionalInformation().get("id_token").toString();
-            final Jwt tokenDecoded = JwtHelper.decode(idToken);
-            System.out.println("===== : " + tokenDecoded.getClaims());
-
+            String kid = JwtHelper.headers(idToken)
+                .get("kid");
+            final Jwt tokenDecoded = JwtHelper.decodeAndVerify(idToken, verifier(kid));
             final Map<String, String> authInfo = new ObjectMapper().readValue(tokenDecoded.getClaims(), Map.class);
-
+            verifyClaims(authInfo);
             final OpenIdConnectUserDetails user = new OpenIdConnectUserDetails(authInfo, accessToken);
             return new UsernamePasswordAuthenticationToken(user, null, user.getAuthorities());
-        } catch (final InvalidTokenException e) {
+        } catch (final Exception e) {
             throw new BadCredentialsException("Could not obtain user details from token", e);
         }
 
     }
 
+    public void verifyClaims(Map claims) {
+        int exp = (int) claims.get("exp");
+        Date expireDate = new Date(exp * 1000L);
+        Date now = new Date();
+        if (expireDate.before(now) || !claims.get("iss").equals(issuer) || !claims.get("aud").equals(clientId)) {
+            throw new RuntimeException("Invalid claims");
+        }
+    }
+
+
+    private RsaVerifier verifier(String kid) throws Exception {
+        JwkProvider provider = new UrlJwkProvider(new URL(jwkUrl));
+        Jwk jwk = provider.get(kid);
+        return new RsaVerifier((RSAPublicKey) jwk.getPublicKey());
+    }
+
     public void setRestTemplate(OAuth2RestTemplate restTemplate2) {
         restTemplate = restTemplate2;
 
diff --git a/spring-security-openid/src/main/resources/application.properties.sample.properties b/spring-security-openid/src/main/resources/application.properties.sample.properties
index 3b4f7716f0..49022bf280 100644
--- a/spring-security-openid/src/main/resources/application.properties.sample.properties
+++ b/spring-security-openid/src/main/resources/application.properties.sample.properties
@@ -3,4 +3,6 @@ google.clientId=TODO
 google.clientSecret=TODO
 google.accessTokenUri=https://www.googleapis.com/oauth2/v3/token
 google.userAuthorizationUri=https://accounts.google.com/o/oauth2/auth
-google.redirectUri=http://localhost:8081/google-login
\ No newline at end of file
+google.redirectUri=http://localhost:8081/google-login
+google.issuer=accounts.google.com
+google.jwkUrl=https://www.googleapis.com/oauth2/v2/certs
\ No newline at end of file
diff --git a/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/BuildConfig.java b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/BuildConfig.java
new file mode 100644
index 0000000000..85233bc278
--- /dev/null
+++ b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/BuildConfig.java
@@ -0,0 +1,8 @@
+/*___Generated_by_IDEA___*/
+
+package com.baeldung.petstore.client.invoker;
+
+/* This stub is only used by the IDE. It is NOT the BuildConfig class actually packed into the APK */
+public final class BuildConfig {
+  public final static boolean DEBUG = Boolean.parseBoolean(null);
+}
\ No newline at end of file
diff --git a/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/Manifest.java b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/Manifest.java
new file mode 100644
index 0000000000..06c202e733
--- /dev/null
+++ b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/Manifest.java
@@ -0,0 +1,7 @@
+/*___Generated_by_IDEA___*/
+
+package com.baeldung.petstore.client.invoker;
+
+/* This stub is only used by the IDE. It is NOT the Manifest class actually packed into the APK */
+public final class Manifest {
+}
\ No newline at end of file
diff --git a/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/R.java b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/R.java
new file mode 100644
index 0000000000..41e2b545fb
--- /dev/null
+++ b/spring-swagger-codegen/spring-swagger-codegen-api-client/src/main/gen/com/baeldung/petstore/client/invoker/R.java
@@ -0,0 +1,7 @@
+/*___Generated_by_IDEA___*/
+
+package com.baeldung.petstore.client.invoker;
+
+/* This stub is only used by the IDE. It is NOT the R class actually packed into the APK */
+public final class R {
+}
\ No newline at end of file
diff --git a/spring-swagger-codegen/spring-swagger-codegen-app/pom.xml b/spring-swagger-codegen/spring-swagger-codegen-app/pom.xml
index f42fc5c2e2..b7b898237f 100644
--- a/spring-swagger-codegen/spring-swagger-codegen-app/pom.xml
+++ b/spring-swagger-codegen/spring-swagger-codegen-app/pom.xml
@@ -9,7 +9,7 @@
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>1.5.6.RELEASE</version>
+        <version>1.5.10.RELEASE</version>
     </parent>
 
     <dependencies>
diff --git a/testing-modules/junit-5/pom.xml b/testing-modules/junit-5/pom.xml
index 585232b3fe..28a29d8545 100644
--- a/testing-modules/junit-5/pom.xml
+++ b/testing-modules/junit-5/pom.xml
@@ -20,7 +20,7 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <java.version>1.8</java.version>
-        <junit.jupiter.version>5.0.2</junit.jupiter.version>
+        <junit.jupiter.version>5.1.0</junit.jupiter.version>
         <junit.platform.version>1.0.1</junit.platform.version>
         <junit.vintage.version>4.12.1</junit.vintage.version>
         <log4j2.version>2.8.2</log4j2.version>
diff --git a/vavr/pom.xml b/vavr/pom.xml
index f9fed7d4fc..28747af3ee 100644
--- a/vavr/pom.xml
+++ b/vavr/pom.xml
@@ -1,17 +1,15 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>vavr</artifactId>
     <version>1.0</version>
     <name>vavr</name>
 
-    <parent>
-        <groupId>org.springframework.boot</groupId>
-        <artifactId>spring-boot-starter-parent</artifactId>
-        <version>1.5.6.RELEASE</version>
-        <relativePath/>
-        <!--  lookup parent from repository  -->
+   <parent>
+        <artifactId>parent-boot-5</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-boot-5</relativePath>
     </parent>
 
     <dependencies>
@@ -21,12 +19,6 @@
             <version>${vavr.version}</version>
         </dependency>
 
-        <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>${junit.version}</version>
-        </dependency>
-		
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jpa</artifactId>
@@ -42,15 +34,15 @@
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>
-        
+
         <dependency>
-    <groupId>org.awaitility</groupId>
-    <artifactId>awaitility</artifactId>
-    <version>${awaitility.version}</version>
-    <scope>test</scope>
-</dependency>
+            <groupId>org.awaitility</groupId>
+            <artifactId>awaitility</artifactId>
+            <version>${awaitility.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
-	
+
     <repositories>
         <repository>
             <id>spring-snapshot</id>
@@ -66,20 +58,13 @@
             <url>https://repo.spring.io/libs-snapshot</url>
         </repository>
     </repositories>
-	
-	<pluginRepositories>
+
+    <pluginRepositories>
         <pluginRepository>
             <id>spring-snapshots</id>
             <url>http://repo.spring.io/snapshot</url>
         </pluginRepository>
     </pluginRepositories>
-	
-    <properties>
-        <java.version>1.8</java.version>
-        <vavr.version>0.9.1</vavr.version>
-        <junit.version>4.12</junit.version>
-        <awaitility.version>3.0.0</awaitility.version>
-    </properties>
 
     <build>
         <plugins>
@@ -97,10 +82,16 @@
                         <exclude>**/JdbcTest.java</exclude>
                         <exclude>**/*LiveTest.java</exclude>
                     </excludes>
-
                 </configuration>
             </plugin>
         </plugins>
     </build>
 
+    <properties>
+        <java.version>1.8</java.version>
+        <vavr.version>0.9.1</vavr.version>
+        <junit.version>4.12</junit.version>
+        <awaitility.version>3.0.0</awaitility.version>
+    </properties>
+
 </project>
\ No newline at end of file
diff --git a/vavr/src/test/java/com/baeldung/vavr/VavrUnitTest.java b/vavr/src/test/java/com/baeldung/vavr/VavrUnitTest.java
index 08a5e20b40..7beb75632e 100644
--- a/vavr/src/test/java/com/baeldung/vavr/VavrUnitTest.java
+++ b/vavr/src/test/java/com/baeldung/vavr/VavrUnitTest.java
@@ -216,11 +216,11 @@ public class VavrUnitTest {
         assertEquals(-1, errorSentinel);
     }
 
-    // @Test(expected = ArithmeticException.class)
-    // public void givenBadCode_whenTryHandles_thenCorrect3() {
-    // Try<Integer> result = Try.of(() -> 1 / 0);
-    // result.getOrElseThrow(ArithmeticException::new);
-    // }
+     @Test(expected = RuntimeException.class)
+     public void givenBadCode_whenTryHandles_thenCorrect3() {
+        Try<Integer> result = Try.of(() -> 1 / 0);
+        result.getOrElseThrow(e->new RuntimeException(e));//re-throw different ex type
+     }
 
     // lazy
     @Test