Merge branch 'master' of https://github.com/eugenp/tutorials

algorithms/README.md

@@ -14,3 +14,4 @@
 - [Bubble Sort in Java](http://www.baeldung.com/java-bubble-sort)
 - [Introduction to JGraphT](http://www.baeldung.com/jgrapht)
 - [Introduction to Minimax Algorithm](http://www.baeldung.com/java-minimax-algorithm)
+- [How to Calculate Levenshtein Distance in Java?](http://www.baeldung.com/java-levenshtein-distance)

algorithms/src/main/java/com/baeldung/algorithms/prime/PrimeGenerator.java

@@ -0,0 +1,59 @@
+package com.baeldung.algorithms.prime;
+
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public class PrimeGenerator {
+    public static List<Integer> sieveOfEratosthenes(int n) {
+        final boolean prime[] = new boolean[n + 1];
+        Arrays.fill(prime, true);
+
+        for (int p = 2; p * p <= n; p++) {
+            if (prime[p]) {
+                for (int i = p * 2; i <= n; i += p)
+                    prime[i] = false;
+            }
+        }
+
+        final List<Integer> primes = new LinkedList<>();
+        for (int i = 2; i <= n; i++) {
+            if (prime[i])
+                primes.add(i);
+        }
+        return primes;
+    }
+
+    public static List<Integer> primeNumbersBruteForce(int max) {
+        final List<Integer> primeNumbers = new LinkedList<Integer>();
+        for (int i = 2; i <= max; i++) {
+            if (isPrimeBruteForce(i)) {
+                primeNumbers.add(i);
+            }
+        }
+        return primeNumbers;
+    }
+
+    private static boolean isPrimeBruteForce(int x) {
+        for (int i = 2; i < x; i++) {
+            if (x % i == 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public static List<Integer> primeNumbersTill(int max) {
+        return IntStream.rangeClosed(2, max)
+            .filter(x -> isPrime(x))
+            .boxed()
+            .collect(Collectors.toList());
+    }
+
+    private static boolean isPrime(int x) {
+        return IntStream.rangeClosed(2, (int) (Math.sqrt(x)))
+            .allMatch(n -> x % n != 0);
+    }
+}

algorithms/src/test/java/com/baeldung/algorithms/prime/PrimeGeneratorTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.algorithms.prime;
+
+import static com.baeldung.algorithms.prime.PrimeGenerator.*;
+
+import java.util.Arrays;
+import java.util.List;
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+public class PrimeGeneratorTest {
+    @Test
+    public void whenBruteForced_returnsSuccessfully() {
+        final List<Integer> primeNumbers = primeNumbersBruteForce(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+
+    @Test
+    public void whenOptimized_returnsSuccessfully() {
+        final List<Integer> primeNumbers = primeNumbersTill(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+
+    @Test
+    public void whenSieveOfEratosthenes_returnsSuccessfully() {
+        final List<Integer> primeNumbers = sieveOfEratosthenes(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+}

apache-spark/README.md

@@ -0,0 +1,3 @@
+### Relevant articles
+
+- [Introduction to Apache Spark](http://www.baeldung.com/apache-spark)

cas/cas-secured-app/pom.xml

@@ -65,6 +65,24 @@
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
 			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-surefire-plugin</artifactId>
+				<version>${maven-surefire-plugin.version}</version>
+				<configuration>
+					<forkCount>3</forkCount>
+					<reuseForks>true</reuseForks>
+					<excludes>
+						<exclude>**/*IntegrationTest.java</exclude>
+						<exclude>**/*LongRunningUnitTest.java</exclude>
+						<exclude>**/*ManualTest.java</exclude>
+						<exclude>**/JdbcTest.java</exclude>
+						<exclude>**/*LiveTest.java</exclude>
+					</excludes>
+
+				</configuration>
+			</plugin>
+
 		</plugins>
 	</build>
 
@@ -107,4 +125,5 @@
 	</pluginRepositories>
 
 
+
 </project>

cas/cas-secured-app/src/test/java/com/baeldung/cassecuredapp/CasSecuredAppApplicationIntegrationTest.java

@@ -7,7 +7,7 @@ import org.springframework.test.context.junit4.SpringRunner;
 
 @RunWith(SpringRunner.class)
 @SpringBootTest
-public class CasSecuredAppApplicationTests {
+public class CasSecuredAppApplicationIntegrationTest {
 
 	@Test
 	public void contextLoads() {

core-java-8/src/main/java/com/baeldung/datetime/DateToLocalDateConverter.java

@@ -0,0 +1,35 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows different ways of converting java.util.Date into java.time.LocalDate.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateConverter {
+
+    public static LocalDate convertToLocalDateViaInstant(Date dateToConvert) {
+        return dateToConvert.toInstant()
+            .atZone(ZoneId.systemDefault())
+            .toLocalDate();
+    }
+
+    public static LocalDate convertToLocalDateViaSqlDate(Date dateToConvert) {
+        return new java.sql.Date(dateToConvert.getTime()).toLocalDate();
+    }
+
+    public static LocalDate convertToLocalDateViaMilisecond(Date dateToConvert) {
+        return Instant.ofEpochMilli(dateToConvert.getTime())
+            .atZone(ZoneId.systemDefault())
+            .toLocalDate();
+    }
+
+}

core-java-8/src/main/java/com/baeldung/datetime/DateToLocalDateTimeConverter.java

@@ -0,0 +1,35 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows different ways of converting java.util.Date into java.time.LocalDateTime. 
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateTimeConverter {
+
+    public static LocalDateTime convertToLocalDateTimeViaInstant(Date dateToConvert) {
+        return dateToConvert.toInstant()
+            .atZone(ZoneId.systemDefault())
+            .toLocalDateTime();
+    }
+
+    public static LocalDateTime convertToLocalDateTimeViaSqlTimestamp(Date dateToConvert) {
+        return new java.sql.Timestamp(dateToConvert.getTime()).toLocalDateTime();
+    }
+
+    public static LocalDateTime convertToLocalDateTimeViaMilisecond(Date dateToConvert) {
+        return Instant.ofEpochMilli(dateToConvert.getTime())
+            .atZone(ZoneId.systemDefault())
+            .toLocalDateTime();
+    }
+
+}

core-java-8/src/main/java/com/baeldung/datetime/LocalDateTimeToDateConverter.java

@@ -0,0 +1,27 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows different ways of converting java.time.LocalDateTime into java.util.Date. 
+ *  
+ * @author abialas
+ *
+ */
+public class LocalDateTimeToDateConverter {
+
+    public static Date convertToDateViaSqlTimestamp(LocalDateTime dateToConvert) {
+        return java.sql.Timestamp.valueOf(dateToConvert);
+    }
+
+    public static Date convertToDateViaInstant(LocalDateTime dateToConvert) {
+        return java.util.Date.from(dateToConvert.atZone(ZoneId.systemDefault())
+            .toInstant());
+    }
+
+}

core-java-8/src/main/java/com/baeldung/datetime/LocalDateToDateConverter.java

@@ -0,0 +1,28 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows different ways of converting java.time.LocalDate into java.util.Date. 
+ *  
+ * @author abialas
+ *
+ */
+public class LocalDateToDateConverter {
+
+    public static Date convertToDateViaSqlDate(LocalDate dateToConvert) {
+        return java.sql.Date.valueOf(dateToConvert);
+    }
+
+    public static Date convertToDateViaInstant(LocalDate dateToConvert) {
+        return java.util.Date.from(dateToConvert.atStartOfDay()
+            .atZone(ZoneId.systemDefault())
+            .toInstant());
+    }
+
+}

core-java-8/src/main/java/com/baeldung/prime/PrimeGenerator.java

@@ -0,0 +1,59 @@
+package com.baeldung.prime;
+
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public class PrimeGenerator {
+    public static List<Integer> sieveOfEratosthenes(int n) {
+        final boolean prime[] = new boolean[n + 1];
+        Arrays.fill(prime, true);
+
+        for (int p = 2; p * p <= n; p++) {
+            if (prime[p]) {
+                for (int i = p * 2; i <= n; i += p)
+                    prime[i] = false;
+            }
+        }
+
+        final List<Integer> primes = new LinkedList<>();
+        for (int i = 2; i <= n; i++) {
+            if (prime[i])
+                primes.add(i);
+        }
+        return primes;
+    }
+
+    public static List<Integer> primeNumbersBruteForce(int max) {
+        final List<Integer> primeNumbers = new LinkedList<Integer>();
+        for (int i = 2; i <= max; i++) {
+            if (isPrimeBruteForce(i)) {
+                primeNumbers.add(i);
+            }
+        }
+        return primeNumbers;
+    }
+
+    private static boolean isPrimeBruteForce(int x) {
+        for (int i = 2; i < x; i++) {
+            if (x % i == 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public static List<Integer> primeNumbersTill(int max) {
+        return IntStream.rangeClosed(2, max)
+            .filter(x -> isPrime(x))
+            .boxed()
+            .collect(Collectors.toList());
+    }
+
+    private static boolean isPrime(int x) {
+        return IntStream.rangeClosed(2, (int) (Math.sqrt(x)))
+            .allMatch(n -> x % n != 0);
+    }
+}

core-java-8/src/test/java/com/baeldung/datetime/DateToLocalDateConverterTest.java

@@ -0,0 +1,72 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoField;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+/**
+ * 
+ * JUnits for {@link DateToLocalDateConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaInstant() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDate localDate = DateToLocalDateConverter.convertToLocalDateViaInstant(dateToConvert);
+
+        // then
+        assertEquals(2010, localDate.get(ChronoField.YEAR));
+        assertEquals(11, localDate.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDate.get(ChronoField.DAY_OF_MONTH));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaMiliseconds() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDate localDate = DateToLocalDateConverter.convertToLocalDateViaMilisecond(dateToConvert);
+
+        // then
+        assertEquals(2010, localDate.get(ChronoField.YEAR));
+        assertEquals(11, localDate.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDate.get(ChronoField.DAY_OF_MONTH));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaSqlDate() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDate localDate = DateToLocalDateConverter.convertToLocalDateViaSqlDate(dateToConvert);
+
+        // then
+        assertEquals(2010, localDate.get(ChronoField.YEAR));
+        assertEquals(11, localDate.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDate.get(ChronoField.DAY_OF_MONTH));
+    }
+
+}

core-java-8/src/test/java/com/baeldung/datetime/DateToLocalDateTimeConverterTest.java

@@ -0,0 +1,78 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDateTime;
+import java.time.temporal.ChronoField;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+/**
+ * 
+ * JUnits for {@link DateToLocalDateTimeConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateTimeConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010time8hour20minWhenConvertViaInstant() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10, 8, 20);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDateTime localDateTime = DateToLocalDateTimeConverter.convertToLocalDateTimeViaInstant(dateToConvert);
+
+        // then
+        assertEquals(2010, localDateTime.get(ChronoField.YEAR));
+        assertEquals(11, localDateTime.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDateTime.get(ChronoField.DAY_OF_MONTH));
+        assertEquals(8, localDateTime.get(ChronoField.HOUR_OF_DAY));
+        assertEquals(20, localDateTime.get(ChronoField.MINUTE_OF_HOUR));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010time8hour20minWhenConvertViaMiliseconds() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10, 8, 20);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDateTime localDateTime = DateToLocalDateTimeConverter.convertToLocalDateTimeViaMilisecond(dateToConvert);
+
+        // then
+        assertEquals(2010, localDateTime.get(ChronoField.YEAR));
+        assertEquals(11, localDateTime.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDateTime.get(ChronoField.DAY_OF_MONTH));
+        assertEquals(8, localDateTime.get(ChronoField.HOUR_OF_DAY));
+        assertEquals(20, localDateTime.get(ChronoField.MINUTE_OF_HOUR));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010time8hour20minWhenConvertViaSqlTimestamp() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10, 8, 20);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDateTime localDateTime = DateToLocalDateTimeConverter.convertToLocalDateTimeViaSqlTimestamp(dateToConvert);
+
+        // then
+        assertEquals(2010, localDateTime.get(ChronoField.YEAR));
+        assertEquals(11, localDateTime.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDateTime.get(ChronoField.DAY_OF_MONTH));
+        assertEquals(8, localDateTime.get(ChronoField.HOUR_OF_DAY));
+        assertEquals(20, localDateTime.get(ChronoField.MINUTE_OF_HOUR));
+    }
+
+}

core-java-8/src/test/java/com/baeldung/datetime/LocalDateTimeToDateConverterTest.java

@@ -0,0 +1,61 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDateTime;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+/**
+ * 
+ * JUnits for {@link LocalDateTimeToDateConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class LocalDateTimeToDateConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010time8hour20minWhenConvertViaInstant() {
+        // given
+        LocalDateTime dateToConvert = LocalDateTime.of(2010, 11, 10, 8, 20);
+
+        // when
+        Date date = LocalDateTimeToDateConverter.convertToDateViaInstant(dateToConvert);
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(date);
+
+        // then
+        assertEquals(2010, calendar.get(Calendar.YEAR));
+        assertEquals(10, calendar.get(Calendar.MONTH));
+        assertEquals(10, calendar.get(Calendar.DAY_OF_MONTH));
+        assertEquals(8, calendar.get(Calendar.HOUR));
+        assertEquals(20, calendar.get(Calendar.MINUTE));
+        assertEquals(0, calendar.get(Calendar.SECOND));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaSqlTimestamp() {
+        // given
+        LocalDateTime dateToConvert = LocalDateTime.of(2010, 11, 10, 8, 20);
+
+        // when
+        Date date = LocalDateTimeToDateConverter.convertToDateViaSqlTimestamp(dateToConvert);
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(date);
+
+        // then
+        assertEquals(2010, calendar.get(Calendar.YEAR));
+        assertEquals(10, calendar.get(Calendar.MONTH));
+        assertEquals(10, calendar.get(Calendar.DAY_OF_MONTH));
+        assertEquals(8, calendar.get(Calendar.HOUR));
+        assertEquals(20, calendar.get(Calendar.MINUTE));
+        assertEquals(0, calendar.get(Calendar.SECOND));
+    }
+
+}

core-java-8/src/test/java/com/baeldung/datetime/LocalDateToDateConverterTest.java

@@ -0,0 +1,55 @@
+/**
+ * 
+ */
+package com.baeldung.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDate;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+/**
+ * 
+ * JUnits for {@link LocalDateToDateConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class LocalDateToDateConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaInstant() {
+        // given
+        LocalDate dateToConvert = LocalDate.of(2010, 11, 10);
+
+        // when
+        Date date = LocalDateToDateConverter.convertToDateViaInstant(dateToConvert);
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(date);
+
+        // then
+        assertEquals(2010, calendar.get(Calendar.YEAR));
+        assertEquals(10, calendar.get(Calendar.MONTH));
+        assertEquals(10, calendar.get(Calendar.DAY_OF_MONTH));
+    }
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertViaSqlDate() {
+        // given
+        LocalDate dateToConvert = LocalDate.of(2010, 11, 10);
+
+        // when
+        Date date = LocalDateToDateConverter.convertToDateViaSqlDate(dateToConvert);
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(date);
+
+        // then
+        assertEquals(2010, calendar.get(Calendar.YEAR));
+        assertEquals(10, calendar.get(Calendar.MONTH));
+        assertEquals(10, calendar.get(Calendar.DAY_OF_MONTH));
+    }
+
+}

core-java-8/src/test/java/com/baeldung/prime/PrimeGeneratorTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.prime;
+
+import static com.baeldung.prime.PrimeGenerator.*;
+
+import java.util.Arrays;
+import java.util.List;
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+public class PrimeGeneratorTest {
+    @Test
+    public void whenBruteForced_returnsSuccessfully() {
+        final List<Integer> primeNumbers = primeNumbersBruteForce(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+
+    @Test
+    public void whenOptimized_returnsSuccessfully() {
+        final List<Integer> primeNumbers = primeNumbersTill(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+
+    @Test
+    public void whenSieveOfEratosthenes_returnsSuccessfully() {
+        final List<Integer> primeNumbers = sieveOfEratosthenes(20);
+        assertEquals(Arrays.asList(new Integer[] { 2, 3, 5, 7, 11, 13, 17, 19 }), primeNumbers);
+    }
+}

core-java-9/src/main/java/com/baeldung/java9/datetime/DateToLocalDateConverter.java

@@ -0,0 +1,22 @@
+/**
+ * 
+ */
+package com.baeldung.java9.datetime;
+
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows a way to convert java.util.Date into java.time.LocalDate with new Java 1.9.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateConverter {
+
+    public static LocalDate convertToLocalDate(Date dateToConvert) {
+        return LocalDate.ofInstant(dateToConvert.toInstant(), ZoneId.systemDefault());
+    }
+
+}

core-java-9/src/main/java/com/baeldung/java9/datetime/DateToLocalDateTimeConverter.java

@@ -0,0 +1,22 @@
+/**
+ * 
+ */
+package com.baeldung.java9.datetime;
+
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.util.Date;
+
+/**
+ * Class which shows a way to convert java.util.Date into java.time.LocalDateTime with new Java 1.9.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateTimeConverter {
+
+    public static LocalDateTime convertToLocalDateTime(Date dateToConvert) {
+        return LocalDateTime.ofInstant(dateToConvert.toInstant(), ZoneId.systemDefault());
+    }
+
+}

core-java-9/src/test/java/com/baeldung/java9/datetime/DateToLocalDateConverterTest.java

@@ -0,0 +1,41 @@
+/**
+ * 
+ */
+package com.baeldung.java9.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoField;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+import com.baeldung.java9.datetime.DateToLocalDateConverter;
+
+/**
+ * JUnits for {@link DateToLocalDateConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010WhenConvertToLocalDate() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDate localDateTime = DateToLocalDateConverter.convertToLocalDate(dateToConvert);
+
+        // then
+        assertEquals(2010, localDateTime.get(ChronoField.YEAR));
+        assertEquals(11, localDateTime.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDateTime.get(ChronoField.DAY_OF_MONTH));
+    }
+
+}

core-java-9/src/test/java/com/baeldung/java9/datetime/DateToLocalDateTimeConverterTest.java

@@ -0,0 +1,43 @@
+/**
+ * 
+ */
+package com.baeldung.java9.datetime;
+
+import static org.junit.Assert.assertEquals;
+
+import java.time.LocalDateTime;
+import java.time.temporal.ChronoField;
+import java.util.Calendar;
+import java.util.Date;
+
+import org.junit.Test;
+
+import com.baeldung.java9.datetime.DateToLocalDateTimeConverter;
+
+/**
+ * JUnits for {@link DateToLocalDateTimeConverter} class.
+ * 
+ * @author abialas
+ *
+ */
+public class DateToLocalDateTimeConverterTest {
+
+    @Test
+    public void shouldReturn10thNovember2010time8hour20minWhenConvertViaInstant() {
+        // given
+        Calendar calendar = Calendar.getInstance();
+        calendar.set(2010, 10, 10, 8, 20);
+        Date dateToConvert = calendar.getTime();
+
+        // when
+        LocalDateTime localDateTime = DateToLocalDateTimeConverter.convertToLocalDateTime(dateToConvert);
+
+        // then
+        assertEquals(2010, localDateTime.get(ChronoField.YEAR));
+        assertEquals(11, localDateTime.get(ChronoField.MONTH_OF_YEAR));
+        assertEquals(10, localDateTime.get(ChronoField.DAY_OF_MONTH));
+        assertEquals(8, localDateTime.get(ChronoField.HOUR_OF_DAY));
+        assertEquals(20, localDateTime.get(ChronoField.MINUTE_OF_HOUR));
+    }
+
+}

core-java-concurrency/README.md

@@ -30,3 +30,4 @@
 - [Guide to Volatile Keyword in Java](http://www.baeldung.com/java-volatile)
 - [Overview of the java.util.concurrent](http://www.baeldung.com/java-util-concurrent)
 - [Semaphores in Java](http://www.baeldung.com/java-semaphore)
+- [Daemon Threads in Java](http://www.baeldung.com/java-daemon-thread)

core-java-concurrency/src/main/java/com/baeldung/concurrent/stopping/ControlSubThread.java

@@ -0,0 +1,52 @@
+package com.baeldung.concurrent.stopping;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+public class ControlSubThread implements Runnable {
+
+    private Thread worker;
+    private int interval = 100;
+    private AtomicBoolean running = new AtomicBoolean(false);
+    private AtomicBoolean stopped = new AtomicBoolean(true);
+
+
+    public ControlSubThread(int sleepInterval) {
+        interval = sleepInterval;
+    }
+
+    public void start() {
+        worker = new Thread(this);
+        worker.start();
+    }
+
+    public void stop() {
+        running.set(false);
+    }
+
+    public void interrupt() {
+        running.set(false);
+        worker.interrupt();
+    }
+
+    boolean isRunning() {
+        return running.get();
+    }
+
+    boolean isStopped() {
+        return stopped.get();
+    }
+
+    public void run() {
+        running.set(true);
+        stopped.set(false);
+        while (running.get()) {
+            try {
+                Thread.sleep(interval);
+            } catch (InterruptedException e) {
+                // no-op, just loop again
+            }
+            // do something
+        }
+        stopped.set(true);
+    }
+}

core-java-concurrency/src/test/java/com/baeldung/concurrent/runnable/RunnableVsThreadLiveTest.java

@@ -1,24 +1,21 @@
 package com.baeldung.concurrent.runnable;
 
 import java.util.concurrent.Callable;
-import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 
 import org.apache.commons.lang3.RandomUtils;
-import org.junit.After;
 import org.junit.AfterClass;
-import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-public class RunnableVsThreadTest {
+public class RunnableVsThreadLiveTest {
 
 	private static Logger log = 
-	  LoggerFactory.getLogger(RunnableVsThreadTest.class);
+	  LoggerFactory.getLogger(RunnableVsThreadLiveTest.class);
 
 	private static ExecutorService executorService;
 	
@@ -77,9 +74,7 @@ public class RunnableVsThreadTest {
 	public void givenACallableAsLambda_whenSubmitToES_thenResult() 
 	  throws Exception {
 		
-		Future<Integer> future = executorService.submit(() -> {
-		  return RandomUtils.nextInt(0, 100);
-		});
+		Future<Integer> future = executorService.submit(() -> RandomUtils.nextInt(0, 100));
 		
 		log.info("Result from callable: {}", future.get());
 	}
@@ -99,7 +94,7 @@ class SimpleThread extends Thread{
 	
 	private String message;
 	
-	public SimpleThread(String message) {
+	SimpleThread(String message) {
 		this.message = message;
 	}
 	
@@ -116,7 +111,7 @@ class SimpleRunnable implements Runnable {
 	
 	private String message;
 	
-	public SimpleRunnable(String message) {
+	SimpleRunnable(String message) {
 		this.message = message;
 	}
 	

core-java-concurrency/src/test/java/com/baeldung/concurrent/stopping/StopThreadTest.java

@@ -0,0 +1,50 @@
+package com.baeldung.concurrent.stopping;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class StopThreadTest {
+
+    @Test
+    public void whenStoppedThreadIsStopped() throws InterruptedException {
+
+        int interval = 100;
+
+        ControlSubThread controlSubThread = new ControlSubThread(interval);
+        controlSubThread.start();
+
+        // Give things a chance to get set up
+        Thread.sleep(interval);
+        assertTrue(controlSubThread.isRunning());
+        assertFalse(controlSubThread.isStopped());
+
+        // Stop it and make sure the flags have been reversed
+        controlSubThread.stop();
+        Thread.sleep(interval);
+        assertTrue(controlSubThread.isStopped());
+    }
+
+
+    @Test
+    public void whenInterruptedThreadIsStopped() throws InterruptedException {
+
+        int interval = 5000;
+
+        ControlSubThread controlSubThread = new ControlSubThread(interval);
+        controlSubThread.start();
+
+        // Give things a chance to get set up
+        Thread.sleep(100);
+        assertTrue(controlSubThread.isRunning());
+        assertFalse(controlSubThread.isStopped());
+
+        // Stop it and make sure the flags have been reversed
+        controlSubThread.interrupt();
+
+        // Wait less than the time we would normally sleep, and make sure we exited.
+        Thread.sleep(interval/10);
+        assertTrue(controlSubThread.isStopped());
+    }
+}

core-java/README.md

@@ -114,4 +114,6 @@
 - [StringBuilder and StringBuffer in Java](http://www.baeldung.com/java-string-builder-string-buffer)
 - [Number of Digits in an Integer in Java](http://www.baeldung.com/java-number-of-digits-in-int)
 - [Proxy, Decorator, Adapter and Bridge Patterns](http://www.baeldung.com/java-structural-design-patterns)
-
+- [Creating a Java Compiler Plugin](http://www.baeldung.com/java-build-compiler-plugin)
+- [A Guide to the Static Keyword in Java](http://www.baeldung.com/java-static)
+- [Initializing Arrays in Java](http://www.baeldung.com/java-initialize-array)

core-java/pom.xml

@@ -216,6 +216,13 @@
 		    <artifactId>spring-web</artifactId>
 		    <version>4.3.4.RELEASE</version>
 		</dependency>
+        <dependency>
+            <groupId>com.sun</groupId>
+            <artifactId>tools</artifactId>
+            <version>1.8.0</version>
+            <scope>system</scope>
+            <systemPath>${java.home}/../lib/tools.jar</systemPath>
+        </dependency>
     </dependencies>
 
     <build>

core-java/src/main/java/com/baeldung/breakcontinue/BreakContinue.java

@@ -0,0 +1,138 @@
+package com.baeldung.breakcontinue;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+/**
+ * @author Santosh
+ *
+ */
+public class BreakContinue {
+
+    public static int unlabeledBreak() {
+        String searchName = "Wilson";
+        int counter = 0;
+        List<String> names = Arrays.asList("John", "Peter", "Robert", "Wilson", "Anthony", "Donald", "Richard");
+
+        for (String name : names) {
+            counter++;
+            if (name.equalsIgnoreCase(searchName)) {
+                break;
+            }
+        }
+
+        return counter;
+    }
+
+    public static int unlabeledBreakNestedLoops() {
+        String searchName = "Wilson";
+        int counter = 0;
+        Map<String, List<String>> nameMap = new HashMap<>();
+        nameMap.put("Grade1", Arrays.asList("John", "Peter", "Robert", "Wilson"));
+        nameMap.put("Grade2", Arrays.asList("Anthony", "Donald", "Richard", "Arnold"));
+        nameMap.put("Grade3", Arrays.asList("Wilson", "Michael", "Stephen", "Ryan"));
+
+        Iterator<Entry<String, List<String>>> iterator = nameMap.entrySet()
+            .iterator();
+        Entry<String, List<String>> entry = null;
+        List<String> names = null;
+        while (iterator.hasNext()) {
+            entry = iterator.next();
+            names = entry.getValue();
+            for (String name : names) {
+                if (name.equalsIgnoreCase(searchName)) {
+                    counter++;
+                    break;
+                }
+            }
+        }
+
+        return counter;
+    }
+
+    public static int labeledBreak() {
+        String searchName = "Wilson";
+        int counter = 0;
+        Map<String, List<String>> nameMap = new HashMap<>();
+        nameMap.put("Grade1", Arrays.asList("John", "Peter", "Robert", "Wilson"));
+        nameMap.put("Grade2", Arrays.asList("Anthony", "Donald", "Richard", "Arnold"));
+        nameMap.put("Grade3", Arrays.asList("Wilson", "Michael", "Stephen", "Ryan"));
+
+        Iterator<Entry<String, List<String>>> iterator = nameMap.entrySet()
+            .iterator();
+        Entry<String, List<String>> entry = null;
+        List<String> names = null;
+        compare: 
+        while (iterator.hasNext()) {
+            entry = iterator.next();
+            names = entry.getValue();
+            for (String name : names) {
+                if (name.equalsIgnoreCase(searchName)) {
+                    counter++;
+                    break compare;
+                }
+            }
+        }
+
+        return counter;
+    }
+
+    public static int unlabeledContinue() {
+        String searchName = "Wilson";
+        int counter = 0;
+        Map<String, List<String>> nameMap = new HashMap<>();
+        nameMap.put("Grade1", Arrays.asList("John", "Wilson", "Robert", "Wilson"));
+        nameMap.put("Grade2", Arrays.asList("Anthony", "Donald", "Wilson", "Arnold"));
+        nameMap.put("Grade3", Arrays.asList("Wilson", "Michael", "Wilson", "Ryan"));
+
+        Iterator<Entry<String, List<String>>> iterator = nameMap.entrySet()
+            .iterator();
+        Entry<String, List<String>> entry = null;
+        List<String> names = null;
+        while (iterator.hasNext()) {
+            entry = iterator.next();
+            names = entry.getValue();
+            for (String name : names) {
+                if (!name.equalsIgnoreCase(searchName)) {
+                    continue;
+                }
+
+                counter++;
+            }
+        }
+
+        return counter;
+    }
+
+    public static int labeledContinue() {
+        String searchName = "Wilson";
+        int counter = 0;
+        Map<String, List<String>> nameMap = new HashMap<>();
+        nameMap.put("Grade1", Arrays.asList("John", "Wilson", "Robert", "Wilson"));
+        nameMap.put("Grade2", Arrays.asList("Anthony", "Donald", "Wilson", "Arnold"));
+        nameMap.put("Grade3", Arrays.asList("Wilson", "Michael", "Wilson", "Ryan"));
+
+        Iterator<Entry<String, List<String>>> iterator = nameMap.entrySet()
+            .iterator();
+        Entry<String, List<String>> entry = null;
+        List<String> names = null;
+        compare: 
+        while (iterator.hasNext()) {
+            entry = iterator.next();
+            names = entry.getValue();
+            for (String name : names) {
+                if (name.equalsIgnoreCase(searchName)) {
+                    counter++;
+                    continue compare;
+                }
+            }
+        }
+
+        return counter;
+    }
+
+}

core-java/src/main/java/com/baeldung/javac/Positive.java

@@ -0,0 +1,9 @@
+package com.baeldung.javac;
+
+import java.lang.annotation.*;
+
+@Documented
+@Retention(RetentionPolicy.CLASS)
+@Target({ElementType.PARAMETER})
+public @interface Positive {
+}

core-java/src/main/java/com/baeldung/javac/SampleJavacPlugin.java

@@ -0,0 +1,123 @@
+package com.baeldung.javac;
+
+import com.sun.source.tree.MethodTree;
+import com.sun.source.tree.VariableTree;
+import com.sun.source.util.*;
+import com.sun.tools.javac.api.BasicJavacTask;
+import com.sun.tools.javac.code.TypeTag;
+import com.sun.tools.javac.tree.JCTree;
+import com.sun.tools.javac.tree.TreeMaker;
+import com.sun.tools.javac.util.Context;
+import com.sun.tools.javac.util.Name;
+import com.sun.tools.javac.util.Names;
+
+import javax.tools.JavaCompiler;
+import java.util.*;
+import java.util.stream.Collectors;
+
+import static com.sun.tools.javac.util.List.nil;
+
+/**
+ * A {@link JavaCompiler javac} plugin which inserts {@code >= 0} checks into resulting {@code *.class} files
+ * for numeric method parameters marked by {@link Positive}
+ */
+public class SampleJavacPlugin implements Plugin {
+
+    public static final String NAME = "MyPlugin";
+
+    private static Set<String> TARGET_TYPES = new HashSet<>(Arrays.asList(
+        // Use only primitive types for simplicity
+        byte.class.getName(), short.class.getName(), char.class.getName(), 
+        int.class.getName(), long.class.getName(), float.class.getName(), double.class.getName()));
+
+    @Override
+    public String getName() {
+        return NAME;
+    }
+
+    @Override
+    public void init(JavacTask task, String... args) {
+        Context context = ((BasicJavacTask) task).getContext();
+        task.addTaskListener(new TaskListener() {
+            @Override
+            public void started(TaskEvent e) {
+            }
+
+            @Override
+            public void finished(TaskEvent e) {
+                if (e.getKind() != TaskEvent.Kind.PARSE) {
+                    return;
+                }
+                e.getCompilationUnit()
+                    .accept(new TreeScanner<Void, Void>() {
+                        @Override
+                        public Void visitMethod(MethodTree method, Void v) {
+                            List<VariableTree> parametersToInstrument = method.getParameters()
+                                .stream()
+                                .filter(SampleJavacPlugin.this::shouldInstrument)
+                                .collect(Collectors.toList());
+                            if (!parametersToInstrument.isEmpty()) {
+                                // There is a possible case that more than one argument is marked by @Positive,
+                                // as the checks are added to the method's body beginning, we process parameters RTL
+                                // to ensure correct order.
+                                Collections.reverse(parametersToInstrument);
+                                parametersToInstrument.forEach(p -> addCheck(method, p, context));
+                            }
+                            // There is a possible case that there is a nested class declared in a method's body,
+                            // hence, we want to proceed with method body AST as well.
+                            return super.visitMethod(method, v);
+                        }
+                    }, null);
+            }
+        });
+    }
+
+    private boolean shouldInstrument(VariableTree parameter) {
+        return TARGET_TYPES.contains(parameter.getType().toString())
+          && parameter.getModifiers().getAnnotations()
+            .stream()
+            .anyMatch(a -> Positive.class.getSimpleName().equals(a.getAnnotationType().toString()));
+    }
+
+    private void addCheck(MethodTree method, VariableTree parameter, Context context) {
+        JCTree.JCIf check = createCheck(parameter, context);
+        JCTree.JCBlock body = (JCTree.JCBlock) method.getBody();
+        body.stats = body.stats.prepend(check);
+    }
+
+    private static JCTree.JCIf createCheck(VariableTree parameter, Context context) {
+        TreeMaker factory = TreeMaker.instance(context);
+        Names symbolsTable = Names.instance(context);
+        
+        return factory.at(((JCTree) parameter).pos)
+          .If(factory.Parens(createIfCondition(factory, symbolsTable, parameter)),
+            createIfBlock(factory, symbolsTable, parameter),
+            null);
+    }
+
+    private static JCTree.JCBinary createIfCondition(TreeMaker factory, Names symbolsTable, VariableTree parameter) {
+        Name parameterId = symbolsTable.fromString(parameter.getName().toString());
+        return factory.Binary(JCTree.Tag.LE, 
+          factory.Ident(parameterId), 
+          factory.Literal(TypeTag.INT, 0));
+    }
+
+    private static JCTree.JCBlock createIfBlock(TreeMaker factory, Names symbolsTable, VariableTree parameter) {
+        String parameterName = parameter.getName().toString();
+        Name parameterId = symbolsTable.fromString(parameterName);
+        
+        String errorMessagePrefix = String.format("Argument '%s' of type %s is marked by @%s but got '", 
+          parameterName, parameter.getType(), Positive.class.getSimpleName());
+        String errorMessageSuffix = "' for it";
+        
+        return factory.Block(0, com.sun.tools.javac.util.List.of(
+          factory.Throw(
+            factory.NewClass(null, nil(), 
+              factory.Ident(symbolsTable.fromString(IllegalArgumentException.class.getSimpleName())),
+                com.sun.tools.javac.util.List.of(factory.Binary(JCTree.Tag.PLUS, 
+                  factory.Binary(JCTree.Tag.PLUS, factory.Literal(TypeTag.CLASS, errorMessagePrefix), 
+                    factory.Ident(parameterId)), 
+                    factory.Literal(TypeTag.CLASS, errorMessageSuffix))), null))));
+    }
+
+}

core-java/src/main/resources/META-INF/services/com.sun.source.util.Plugin

@@ -0,0 +1 @@
+com.baeldung.javac.SampleJavacPlugin