Merge pull request #4 from eugenp/master

Pulled from eugenp:master to sync my fork

.gitignore

@@ -1,3 +1,5 @@
+*/bin/*
+
 *.class
 
 # Package Files #

.travis.yml

@@ -1,6 +1,9 @@
 language: java
 
-install: travis_wait 40 mvn -q clean install -Dgib.enabled=true
+install: travis_wait 60 mvn -q test
+
+before_script:
+  - echo "MAVEN_OPTS='-Xmx2048M -Xss128M -XX:MaxPermSize=2048M -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC -XX:+TieredCompilation -XX:TieredStopAtLevel=1 -XX:-UseGCOverheadLimit'" > ~/.mavenrc
 
 jdk:
   - oraclejdk8
@@ -15,9 +18,4 @@ cache:
   - .autoconf
   - $HOME/.m2
   
-  sudo: required
-  
-  env:
-    global:
-      JAVA_OPTS="-Xmx2048M -Xss128M -XX:MaxPermSize=2048M -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC"
-      MAVEN_OPTS="-Xmx2048M -Xss128M -XX:MaxPermSize=2048M -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC"
+

algorithms/pom.xml

@@ -10,9 +10,15 @@
 		<maven-compiler-plugin.version>3.6.0</maven-compiler-plugin.version>
 		<exec-maven-plugin.version>1.5.0</exec-maven-plugin.version>
 		<lombok.version>1.16.12</lombok.version>
+		<commons-math3.version>3.6.1</commons-math3.version>
 	</properties>
 
 	<dependencies>
+		<dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-math3</artifactId>
+            <version>${commons-math3.version}</version>
+        </dependency>
 		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>

algorithms/src/main/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeChecker.java

@@ -0,0 +1,13 @@
+package com.baeldung.algorithms.primechecker;
+
+import java.math.BigInteger;
+
+public class BigIntegerPrimeChecker implements PrimeChecker{
+
+    @Override
+    public boolean isPrime(int number) {
+        BigInteger bigInt = BigInteger.valueOf(number);
+        return bigInt.isProbablePrime(100);
+    }
+
+}

algorithms/src/main/java/com/baeldung/algorithms/primechecker/BruteForcePrimeChecker.java

@@ -0,0 +1,13 @@
+package com.baeldung.algorithms.primechecker;
+
+import java.util.stream.IntStream;
+
+public class BruteForcePrimeChecker implements PrimeChecker{
+
+    @Override
+    public boolean isPrime(int number) {
+        return IntStream.range(2, number).noneMatch(n -> (number % n == 0));
+    }
+
+    
+}       

algorithms/src/main/java/com/baeldung/algorithms/primechecker/OptimisedPrimeChecker.java

@@ -0,0 +1,14 @@
+package com.baeldung.algorithms.primechecker;
+
+import java.util.stream.IntStream;
+
+public class OptimisedPrimeChecker implements PrimeChecker{
+
+    @Override
+    public boolean isPrime(int number) {
+        return IntStream.range(2, (int)Math.sqrt(number) + 1)
+            .noneMatch(n -> (number % n == 0));
+    }
+
+    
+}

algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimeChecker.java

@@ -0,0 +1,6 @@
+package com.baeldung.algorithms.primechecker;
+
+public interface PrimeChecker {
+    
+    public boolean isPrime( int number );
+}

algorithms/src/main/java/com/baeldung/algorithms/primechecker/PrimesPrimeChecker.java

@@ -0,0 +1,12 @@
+package com.baeldung.algorithms.primechecker;
+
+import org.apache.commons.math3.primes.Primes;
+
+public class PrimesPrimeChecker implements PrimeChecker{
+
+    @Override
+    public boolean isPrime(int number) {
+        return Primes.isPrime(number);
+    }
+
+}

algorithms/src/main/java/com/baeldung/automata/RtState.java

@@ -21,12 +21,12 @@ public final class RtState implements State {
     }
 
     public State transit(final CharSequence c) {
-        for(final Transition t : this.transitions) {
-            if(t.isPossible(c)) {
-                return t.state();
-            }
-        }
-        throw new IllegalArgumentException("Input not accepted: " + c);
+        return transitions
+          .stream()
+          .filter(t -> t.isPossible(c))
+          .map(Transition::state)
+          .findAny()
+          .orElseThrow(() -> new IllegalArgumentException("Input not accepted: " + c));
     }
 
     public boolean isFinal() {

algorithms/src/test/java/com/baeldung/algorithms/primechecker/BigIntegerPrimeCheckerTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.algorithms.primechecker;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import com.baeldung.algorithms.primechecker.BigIntegerPrimeChecker;
+import com.baeldung.algorithms.primechecker.PrimeChecker;
+
+public class BigIntegerPrimeCheckerTest {
+
+    PrimeChecker primeChecker = new BigIntegerPrimeChecker();
+    
+    @Test
+    public void givenPrimeNumber_whenCheckIsPrime_thenTrue(){
+        assertTrue(primeChecker.isPrime(13));
+        assertTrue(primeChecker.isPrime(1009));
+    }
+    
+    @Test
+    public void givenNonPrimeNumber_whenCheckIsPrime_thenFalse(){
+        assertTrue(!primeChecker.isPrime(50));
+        assertTrue(!primeChecker.isPrime(1001));
+    }
+    
+}

algorithms/src/test/java/com/baeldung/algorithms/primechecker/BruteForcePrimeCheckerTest.java

@@ -0,0 +1,27 @@
+package com.baeldung.algorithms.primechecker;
+
+import org.junit.Test;
+
+import com.baeldung.algorithms.primechecker.BruteForcePrimeChecker;
+
+import static org.junit.Assert.*;
+
+public class BruteForcePrimeCheckerTest {
+
+    BruteForcePrimeChecker primeChecker = new BruteForcePrimeChecker();
+    
+    @Test
+    public void givenPrimeNumber_whenCheckIsPrime_thenTrue(){
+        assertTrue(primeChecker.isPrime(13));
+        assertTrue(primeChecker.isPrime(1009));
+    }
+    
+    @Test
+    public void givenNonPrimeNumber_whenCheckIsPrime_thenFalse(){
+        assertTrue(!primeChecker.isPrime(50));
+        assertTrue(!primeChecker.isPrime(1001));
+    }
+    
+    
+    
+}

algorithms/src/test/java/com/baeldung/algorithms/primechecker/OptimisedPrimeCheckerTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.algorithms.primechecker;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import com.baeldung.algorithms.primechecker.OptimisedPrimeChecker;
+import com.baeldung.algorithms.primechecker.PrimeChecker;
+
+public class OptimisedPrimeCheckerTest {
+
+    PrimeChecker primeChecker = new OptimisedPrimeChecker();
+    
+    @Test
+    public void givenPrimeNumber_whenCheckIsPrime_thenTrue(){
+        assertTrue(primeChecker.isPrime(13));
+        assertTrue(primeChecker.isPrime(1009));
+    }
+    
+    @Test
+    public void givenNonPrimeNumber_whenCheckIsPrime_thenFalse(){
+        assertTrue(!primeChecker.isPrime(50));
+        assertTrue(!primeChecker.isPrime(1001));
+    }
+    
+}

algorithms/src/test/java/com/baeldung/algorithms/primechecker/PrimesPrimeCheckerTest.java

@@ -0,0 +1,25 @@
+package com.baeldung.algorithms.primechecker;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import com.baeldung.algorithms.primechecker.PrimeChecker;
+import com.baeldung.algorithms.primechecker.PrimesPrimeChecker;
+
+public class PrimesPrimeCheckerTest {
+    PrimeChecker primeChecker = new PrimesPrimeChecker();
+
+    @Test
+    public void givenPrimeNumber_whenCheckIsPrime_thenTrue() {
+        assertTrue(primeChecker.isPrime(13));
+        assertTrue(primeChecker.isPrime(1009));
+    }
+
+    @Test
+    public void givenNonPrimeNumber_whenCheckIsPrime_thenFalse() {
+        assertTrue(!primeChecker.isPrime(50));
+        assertTrue(!primeChecker.isPrime(1001));
+    }
+
+}

apache-poi/.gitignore

@@ -1 +1,3 @@
 *.docx
+temp.xls
+temp.xlsx

core-java/README.md

@@ -84,4 +84,5 @@
 - [Guide to java.util.concurrent.Locks](http://www.baeldung.com/java-concurrent-locks)
 - [Java Primitive Conversions](http://www.baeldung.com/java-primitive-conversions)
 - [Java Money and the Currency API](http://www.baeldung.com/java-money-and-currency)
+- [Guide to Java 8 Comparator.comparing()](http://www.baeldung.com/java-8-comparator-comparing)
 

core-java/pom.xml

@@ -198,7 +198,6 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>${maven-surefire-plugin.version}</version>
                 <configuration>
                     <excludes>
                         <exclude>**/*IntegrationTest.java</exclude>
@@ -250,6 +249,7 @@
                             <goal>single</goal>
                         </goals>
                         <configuration>
+                            <archiveBaseDirectory>${project.basedir}</archiveBaseDirectory>
                             <archive>
                                 <manifest>
                                     <mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>

core-java/src/main/java/com/baeldung/arraycopy/model/Address.java

@@ -0,0 +1,61 @@
+package com.baeldung.arraycopy.model;
+
+public class Address implements Cloneable {
+    private String country;
+    private String state;
+    private String city;
+    private String street;
+    private String zipcode;
+
+    public String getCountry() {
+        return country;
+    }
+
+    public void setCountry(String country) {
+        this.country = country;
+    }
+
+    public String getState() {
+        return state;
+    }
+
+    public void setState(String state) {
+        this.state = state;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+
+    public String getStreet() {
+        return street;
+    }
+
+    public void setStreet(String street) {
+        this.street = street;
+    }
+
+    public String getZipcode() {
+        return zipcode;
+    }
+
+    public void setZipcode(String zipcode) {
+        this.zipcode = zipcode;
+    }
+
+    @Override
+    protected Object clone() throws CloneNotSupportedException {
+        super.clone();
+        Address address = new Address();
+        address.setCity(this.city);
+        address.setCountry(this.country);
+        address.setState(this.state);
+        address.setStreet(this.street);
+        address.setZipcode(this.zipcode);
+        return address;
+    }
+}

core-java/src/main/java/com/baeldung/arraycopy/model/Employee.java

@@ -0,0 +1,25 @@
+package com.baeldung.arraycopy.model;
+
+import java.io.Serializable;
+
+public class Employee implements Serializable {
+    private static final long serialVersionUID = -2454619097207585825L;
+    private int id;
+    private String name;
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

core-java/src/main/java/com/baeldung/pow/PowerExample.java

@@ -0,0 +1,19 @@
+package com.baeldung.pow;
+
+import java.text.DecimalFormat;
+
+public class PowerExample {
+
+    public static void main(String[] args) {
+
+        int intResult = (int) Math.pow(2, 3);
+        System.out.println("Math.pow(2, 3) = " + intResult);
+
+        double dblResult = Math.pow(4.2, 3);
+        System.out.println("Math.pow(4.2, 3) = " + Math.pow(4.2, 3));
+
+        DecimalFormat df = new DecimalFormat(".00");
+        System.out.println("Math.pow(4.2, 3) rounded = " + df.format(dblResult));
+
+    }
+}

core-java/src/test/java/com/baeldung/arraycopy/ArrayCopyUtilTest.java

@@ -0,0 +1,168 @@
+package com.baeldung.arraycopy;
+
+import com.baeldung.arraycopy.model.Address;
+import com.baeldung.arraycopy.model.Employee;
+import org.apache.commons.lang3.SerializationUtils;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+public class ArrayCopyUtilTest {
+    private static Employee[] employees;
+    private static final int MAX = 2;
+
+    @BeforeClass
+    public static void setup(){
+      createEmployeesArray();
+    }
+
+    private static void createEmployeesArray() {
+        employees = new Employee[MAX];
+          Employee employee;
+          for(int i = 0; i < MAX; i++) {
+              employee = new Employee();
+              employee.setName("Emp"+i);
+              employee.setId(i);
+              employees[i] = employee;
+          }
+    }
+
+    @Test
+    public void givenArrayOfPrimitiveType_whenCopiedViaSystemsArrayCopy_thenSuccessful(){
+        int[] array = {23, 43, 55};
+        int[] copiedArray = new int[3];
+        
+        System.arraycopy(array, 0, copiedArray, 0, 3);
+        
+        Assert.assertArrayEquals(copiedArray, array);
+    }
+
+    @Test
+    public void givenArrayOfPrimitiveType_whenCopiedSubSequenceViaSystemsArrayCopy_thenSuccessful(){
+        int[] array = {23, 43, 55, 12, 65, 88, 92};
+        int[] copiedArray = new int[3];
+        
+        System.arraycopy(array, 2, copiedArray, 0, 3);
+        
+        Assert.assertTrue(3 == copiedArray.length);
+        Assert.assertTrue(copiedArray[0] == array[2]);
+        Assert.assertTrue(copiedArray[1] == array[3]);
+        Assert.assertTrue(copiedArray[2] == array[4]);
+    }
+
+    @Test
+    public void givenArrayOfPrimitiveType_whenCopiedSubSequenceViaArraysCopyOfRange_thenSuccessful(){
+        int[] array = {23, 43, 55, 12, 65, 88, 92};
+        
+        int[] copiedArray = Arrays.copyOfRange(array, 1, 4);
+        
+        Assert.assertTrue(3 == copiedArray.length);
+        Assert.assertTrue(copiedArray[0] == array[1]);
+        Assert.assertTrue(copiedArray[1] == array[2]);
+        Assert.assertTrue(copiedArray[2] == array[3]);
+    }
+
+    @Test
+    public void givenArrayOfPrimitiveType_whenCopiedViaArraysCopyOf_thenValueChangeIsSuccessful(){
+        int[] array = {23, 43, 55, 12};
+        int newLength = array.length;
+        
+        int[] copiedArray = Arrays.copyOf(array, newLength);
+        
+        Assert.assertArrayEquals(copiedArray, array);
+        array[0] = 9;
+        Assert.assertTrue(copiedArray[0] != array[0]);
+        copiedArray[1] = 12;
+        Assert.assertTrue(copiedArray[1] != array[1]);
+    }
+
+    @Test
+    public void givenArrayOfNonPrimitiveType_whenCopiedViaArraysCopyOf_thenDoShallowCopy(){
+        Employee[] copiedArray = Arrays.copyOf(employees, employees.length);
+        
+        Assert.assertArrayEquals(copiedArray, employees);
+        employees[0].setName(employees[0].getName()+"_Changed");
+        //change in employees' element caused change in the copied array
+        Assert.assertTrue(copiedArray[0].getName().equals(employees[0].getName()));
+    }
+
+    @Test
+    public void givenArrayOfPrimitiveType_whenCopiedViaArrayClone_thenValueChangeIsSuccessful(){
+        int[] array = {23, 43, 55, 12};
+        
+        int[] copiedArray = array.clone();
+        
+        Assert.assertArrayEquals(copiedArray, array);
+        array[0] = 9;
+        Assert.assertTrue(copiedArray[0] != array[0]);
+        copiedArray[1] = 12;
+        Assert.assertTrue(copiedArray[1] != array[1]);
+    }
+
+    @Test
+    public void givenArraysOfNonPrimitiveType_whenCopiedViaArrayClone_thenDoShallowCopy(){
+        Employee[] copiedArray = employees.clone();
+        
+        Assert.assertArrayEquals(copiedArray, employees);;
+        employees[0].setName(employees[0].getName()+"_Changed");
+        //change in employees' element changed the copied array
+        Assert.assertTrue(copiedArray[0].getName().equals(employees[0].getName()));
+    }
+
+    @Test
+    public void givenArraysOfCloneableNonPrimitiveType_whenCopiedViaArrayClone_thenDoShallowCopy(){
+        Address[] addresses = createAddressArray();
+        
+        Address[] copiedArray = addresses.clone();
+        
+        addresses[0].setCity(addresses[0].getCity()+"_Changed");
+        Assert.assertArrayEquals(copiedArray, addresses);
+    }
+
+    @Test
+    public void givenArraysOfSerializableNonPrimitiveType_whenCopiedViaSerializationUtils_thenDoDeepCopy(){
+        Employee[] copiedArray = SerializationUtils.clone(employees);
+       
+        employees[0].setName(employees[0].getName()+"_Changed");
+        //change in employees' element didn't change in the copied array
+        Assert.assertFalse(
+            copiedArray[0].getName().equals(employees[0].getName()));
+    }
+    
+    @Test
+    public void givenArraysOfNonPrimitiveType_whenCopiedViaStream_thenDoShallowCopy(){
+        Employee[] copiedArray = Arrays.stream(employees).toArray(Employee[]::new);
+        
+        Assert.assertArrayEquals(copiedArray, employees);
+        employees[0].setName(employees[0].getName()+"_Changed");
+        //change in employees' element didn't change in the copied array
+        Assert.assertTrue(copiedArray[0].getName().equals(employees[0].getName()));
+    }
+    
+    @Test
+    public void givenArraysOfPrimitiveType_whenCopiedViaStream_thenSuccessful(){
+        String[] strArray = {"orange", "red", "green'"};
+        
+        String[] copiedArray = Arrays.stream(strArray).toArray(String[]::new);
+        
+        Assert.assertArrayEquals(copiedArray, strArray);
+    }
+    
+    private Address[] createAddressArray(){
+        Address[] addresses = new Address[1];
+        addresses[0] = createAddress();
+        return addresses;
+    }
+
+    private Address createAddress() {
+        Address address = new Address();
+        address.setCountry("USA");
+        address.setState("CA");
+        address.setCity("San Francisco");
+        address.setStreet("Street 1");
+        address.setZipcode("59999");
+        return address;
+    }
+}

core-java/src/test/java/com/baeldung/concurrent/countdownlatch/CountdownLatchExampleIntegrationTest.java

@@ -12,7 +12,7 @@ import java.util.stream.Stream;
 import static java.util.stream.Collectors.toList;
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class CountdownLatchExampleTest {
+public class CountdownLatchExampleIntegrationTest {
     @Test
     public void whenParallelProcessing_thenMainThreadWillBlockUntilCompletion() throws InterruptedException {
         // Given

core-java/src/test/java/com/baeldung/enums/PizzaUnitTest.java

@@ -1,5 +1,6 @@
 package com.baeldung.enums;
 
+import com.baeldung.enums.Pizza.PizzaStatusEnum;
 import org.junit.Test;
 
 import java.util.ArrayList;
@@ -69,11 +70,31 @@ public class PizzaUnitTest {
     }
 
     @Test
-    public void givenPizaOrder_whenDelivered_thenPizzaGetsDeliveredAndStatusChanges() {
+    public void whenDelivered_thenPizzaGetsDeliveredAndStatusChanges() {
         Pizza pz = new Pizza();
         pz.setStatus(Pizza.PizzaStatusEnum.READY);
         pz.deliver();
         assertTrue(pz.getStatus() == Pizza.PizzaStatusEnum.DELIVERED);
     }
+    
+    @Test
+    public void whenConvertedIntoEnum_thenGetsConvertedCorrectly() {
+        String pizzaEnumValue = "READY";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+        assertTrue(pizzaStatusEnum == PizzaStatusEnum.READY);
+    }
+    
+    @Test(expected = IllegalArgumentException.class)
+    public void whenConvertedIntoEnum_thenThrowsException() {
+        String pizzaEnumValue = "rEAdY";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void givenInvalidEnumValueContentWiseAsString_whenConvertedIntoEnum_thenThrowsException() {
+        String pizzaEnumValue = "invalid";
+        PizzaStatusEnum pizzaStatusEnum = PizzaStatusEnum.valueOf(pizzaEnumValue);
+    }
+    
 
 }

core-java/src/test/java/com/baeldung/java8/comparator/Java8ComparatorTest.java

@@ -60,7 +60,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingComparing_thenCheckingSort() {
+    public void whenComparing_thenSortedByName() {
         Comparator<Employee> employeeNameComparator = Comparator.comparing(Employee::getName);
         Arrays.sort(employees, employeeNameComparator);
 //         System.out.println(Arrays.toString(employees));
@@ -68,7 +68,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingComparingWithComparator_thenCheckingSort() {
+    public void whenComparingWithComparator_thenSortedByNameDesc() {
         Comparator<Employee> employeeNameComparator = Comparator.comparing(Employee::getName, (s1, s2) -> {
             return s2.compareTo(s1);
         });
@@ -76,9 +76,18 @@ public class Java8ComparatorTest {
 //         System.out.println(Arrays.toString(employees));
         assertTrue(Arrays.equals(employees, sortedEmployeesByNameDesc));
     }
+    
+    @Test
+    public void whenReversed_thenSortedByNameDesc() {
+    	Comparator<Employee> employeeNameComparator = Comparator.comparing(Employee::getName);
+    	Comparator<Employee> employeeNameComparatorReversed = employeeNameComparator.reversed();
+        Arrays.sort(employees, employeeNameComparatorReversed);
+//         System.out.println(Arrays.toString(employees));
+        assertTrue(Arrays.equals(employees, sortedEmployeesByNameDesc));
+    }
 
     @Test
-    public void givenEmployeeArray_whenUsingComparingInt_thenCheckingSort() {
+    public void whenComparingInt_thenSortedByAge() {
         Comparator<Employee> employeeAgeComparator = Comparator.comparingInt(Employee::getAge);
         Arrays.sort(employees, employeeAgeComparator);
 //         System.out.println(Arrays.toString(employees));
@@ -86,7 +95,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingComparingLong_thenCheckingSort() {
+    public void whenComparingLong_thenSortedByMobile() {
         Comparator<Employee> employeeMobileComparator = Comparator.comparingLong(Employee::getMobile);
         Arrays.sort(employees, employeeMobileComparator);
 //         System.out.println(Arrays.toString(employees));
@@ -94,7 +103,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingComparingDouble_thenCheckingSort() {
+    public void whenComparingDouble_thenSortedBySalary() {
         Comparator<Employee> employeeSalaryComparator = Comparator.comparingDouble(Employee::getSalary);
         Arrays.sort(employees, employeeSalaryComparator);
 //         System.out.println(Arrays.toString(employees));
@@ -102,7 +111,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingNaturalOrder_thenCheckingSort() {
+    public void whenNaturalOrder_thenSortedByName() {
         Comparator<Employee> employeeNameComparator = Comparator.<Employee> naturalOrder();
         Arrays.sort(employees, employeeNameComparator);
 //         System.out.println(Arrays.toString(employees));
@@ -110,7 +119,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingReverseOrder_thenCheckingSort() {
+    public void whenReverseOrder_thenSortedByNameDesc() {
         Comparator<Employee> employeeNameComparator = Comparator.<Employee> reverseOrder();
         Arrays.sort(employees, employeeNameComparator);
 //        System.out.println(Arrays.toString(employees));
@@ -118,7 +127,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingNullFirst_thenCheckingSort() {
+    public void whenNullsFirst_thenSortedByNameWithNullsFirst() {
         Comparator<Employee> employeeNameComparator = Comparator.comparing(Employee::getName);
         Comparator<Employee> employeeNameComparator_nullFirst = Comparator.nullsFirst(employeeNameComparator);
         Arrays.sort(employeesArrayWithNulls, employeeNameComparator_nullFirst);
@@ -127,7 +136,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingNullLast_thenCheckingSort() {
+    public void whenNullsLast_thenSortedByNameWithNullsLast() {
         Comparator<Employee> employeeNameComparator = Comparator.comparing(Employee::getName);
         Comparator<Employee> employeeNameComparator_nullLast = Comparator.nullsLast(employeeNameComparator);
         Arrays.sort(employeesArrayWithNulls, employeeNameComparator_nullLast);
@@ -136,7 +145,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingThenComparing_thenCheckingSort() {
+    public void whenThenComparing_thenSortedByAgeName() {
         Comparator<Employee> employee_Age_Name_Comparator = Comparator.comparing(Employee::getAge).thenComparing(Employee::getName);
 
         Arrays.sort(someMoreEmployees, employee_Age_Name_Comparator);
@@ -145,7 +154,7 @@ public class Java8ComparatorTest {
     }
 
     @Test
-    public void givenEmployeeArray_whenUsingThenComparingInt_thenCheckingSort() {
+    public void whenThenComparing_thenSortedByNameAge() {
         Comparator<Employee> employee_Name_Age_Comparator = Comparator.comparing(Employee::getName).thenComparingInt(Employee::getAge);
 
         Arrays.sort(someMoreEmployees, employee_Name_Age_Comparator);
@@ -153,40 +162,6 @@ public class Java8ComparatorTest {
         assertTrue(Arrays.equals(someMoreEmployees, sortedEmployeesByNameAge));
     }
 
-     @Before
-     public void printData() {
-//     System.out.println("employees");
-//     System.out.println(Arrays.toString(employees));
-    //
-//     System.out.println("employeesArrayWithNulls");
-//     System.out.println(Arrays.toString(employeesArrayWithNulls));
-    //
-    // System.out.println("sortedEmployeesByName");
-    // System.out.println(Arrays.toString(sortedEmployeesByName));
-    //
-    // System.out.println("sortedEmployeesByNameDesc");
-    // System.out.println(Arrays.toString(sortedEmployeesByNameDesc));
-    //
-    // System.out.println("sortedEmployeesByAge");
-    // System.out.println(Arrays.toString(sortedEmployeesByAge));
-    //
-    // System.out.println("sortedEmployeesByMobile");
-    // System.out.println(Arrays.toString(sortedEmployeesByMobile));
-    //
-    // System.out.println("sortedEmployeesBySalary");
-    // System.out.println(Arrays.toString(sortedEmployeesBySalary));
-    //
-    // System.out.println("sortedEmployeesArray_WithNullsFirst");
-    // System.out.println(Arrays.toString(sortedEmployeesArray_WithNullsFirst));
-    //
-    // System.out.println("sortedEmployeesArray_WithNullsLast");
-    // System.out.println(Arrays.toString(sortedEmployeesArray_WithNullsLast));
-    //
-    // System.out.println("sortedEmployeesByNameAge");
-    // System.out.println(Arrays.toString(sortedEmployeesByNameAge));
-    //
-//     System.out.println("someMoreEmployees");
-//     System.out.println(Arrays.toString(someMoreEmployees));
-    //
-     }
+
 }
+

core-java/src/test/java/com/baeldung/list/flattennestedlist/FlattenNestedListTest.java

@@ -1,52 +1,39 @@
 package com.baeldung.list.flattennestedlist;
 
-import org.junit.Test;
+import static java.util.Arrays.asList;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.stream.Collectors;
 
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import org.hamcrest.collection.IsIterableContainingInOrder;
+import org.junit.Test;
 
 public class FlattenNestedListTest {
+    List<List<String>> lol = asList(asList("one:one"), asList("two:one", "two:two", "two:three"), asList("three:one", "three:two", "three:three", "three:four"));
 
     @Test
-    public void givenListOfListOfString_flattenNestedList1() {
-        // given
-        List<String> ls1 = Arrays.asList("one:one", "one:two", "one:three");
-        List<String> ls2 = Arrays.asList("two:one", "two:two", "two:three");
-        List<String> ls3 = Arrays.asList("three:one", "three:two", "three:three");
+    public void givenString_flattenNestedList1() {
+        List<String> ls = flattenListOfListsImperatively(lol);
 
-        List<List<String>> list = Arrays.asList(ls1, ls2, ls3);
-
-        // when
-        List<String> ls = flattenListOfListsImperatively(list);
-
-        // then
         assertNotNull(ls);
-        assertTrue(ls.size() == 9);
-        //TODO content assertion
+        assertTrue(ls.size() == 8);
+        // assert content
+        assertThat(ls, IsIterableContainingInOrder.contains("one:one", "two:one", "two:two", "two:three", "three:one", "three:two", "three:three", "three:four"));
     }
 
     @Test
-    public void givenListOfListOfString_flattenNestedList2() {
-        // given
-        List<String> ls1 = Arrays.asList("one:one", "one:two", "one:three");
-        List<String> ls2 = Arrays.asList("two:one", "two:two", "two:three");
-        List<String> ls3 = Arrays.asList("three:one", "three:two", "three:three");
+    public void givenString_flattenNestedList2() {
+        List<String> ls = flattenListOfListsStream(lol);
 
-        List<List<String>> list = Arrays.asList(ls1, ls2, ls3);
-
-        // when
-        List<String> ls = flattenListOfListsStream(list);
-
-        // then
         assertNotNull(ls);
-        assertTrue(ls.size() == 9);
-        //TODO content assertion
+        assertTrue(ls.size() == 8);
+        // assert content
+        assertThat(ls, IsIterableContainingInOrder.contains("one:one", "two:one", "two:two", "two:three", "three:one", "three:two", "three:three", "three:four"));
     }
 
     public <T> List<T> flattenListOfListsImperatively(List<List<T>> list) {
@@ -56,9 +43,6 @@ public class FlattenNestedListTest {
     }
 
     public <T> List<T> flattenListOfListsStream(List<List<T>> list) {
-        return list.stream()
-          .flatMap(Collection::stream)
-          .collect(Collectors.toList());
+        return list.stream().flatMap(Collection::stream).collect(Collectors.toList());
     }
-
 }

core-java/src/test/java/org/baeldung/java/shell/JavaProcessUnitIntegrationTest.java

@@ -7,7 +7,7 @@ import java.io.*;
 import java.util.concurrent.Executors;
 import java.util.function.Consumer;
 
-public class JavaProcessUnitTest {
+public class JavaProcessUnitIntegrationTest {
     private static final boolean IS_WINDOWS = System.getProperty("os.name").toLowerCase().startsWith("windows");
 
     private static class StreamGobbler implements Runnable {

core-java/src/test/java/org/baeldung/java/streams/ThreadPoolInParallelStreamIntegrationTest.java

@@ -1,38 +1,38 @@
-package org.baeldung.java.streams;
-
-import org.junit.Test;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ForkJoinPool;
-import java.util.stream.Collectors;
-import java.util.stream.LongStream;
-import java.util.stream.Stream;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
-public class ThreadPoolInParallelStreamTest {
-
-    @Test
-    public void giveRangeOfLongs_whenSummedInParallel_shouldBeEqualToExpectedTotal() throws InterruptedException, ExecutionException {
-        long firstNum = 1;
-        long lastNum = 1_000_000;
-
-        List<Long> aList = LongStream.rangeClosed(firstNum, lastNum).boxed().collect(Collectors.toList());
-
-        ForkJoinPool customThreadPool = new ForkJoinPool(4);
-        long actualTotal = customThreadPool.submit(() -> aList.parallelStream().reduce(0L, Long::sum)).get();
-
-        assertEquals((lastNum + firstNum) * lastNum / 2, actualTotal);
-    }
-
-    @Test
-    public void givenList_whenCallingParallelStream_shouldBeParallelStream() {
-        List<Long> aList = new ArrayList<>();
-        Stream<Long> parallelStream = aList.parallelStream();
-
-        assertTrue(parallelStream.isParallel());
-    }
-}
+package org.baeldung.java.streams;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ForkJoinPool;
+import java.util.stream.Collectors;
+import java.util.stream.LongStream;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class ThreadPoolInParallelStreamIntegrationTest {
+
+    @Test
+    public void giveRangeOfLongs_whenSummedInParallel_shouldBeEqualToExpectedTotal() throws InterruptedException, ExecutionException {
+        long firstNum = 1;
+        long lastNum = 1_000_000;
+
+        List<Long> aList = LongStream.rangeClosed(firstNum, lastNum).boxed().collect(Collectors.toList());
+
+        ForkJoinPool customThreadPool = new ForkJoinPool(4);
+        long actualTotal = customThreadPool.submit(() -> aList.parallelStream().reduce(0L, Long::sum)).get();
+
+        assertEquals((lastNum + firstNum) * lastNum / 2, actualTotal);
+    }
+
+    @Test
+    public void givenList_whenCallingParallelStream_shouldBeParallelStream() {
+        List<Long> aList = new ArrayList<>();
+        Stream<Long> parallelStream = aList.parallelStream();
+
+        assertTrue(parallelStream.isParallel());
+    }
+}

disruptor/pom.xml

@@ -145,6 +145,7 @@
                             <goal>single</goal>
                         </goals>
                         <configuration>
+                            <archiveBaseDirectory>${project.basedir}</archiveBaseDirectory>
                             <archive>
                                 <manifest>
                                     <mainClass>org.baeldung.executable.ExecutableMavenJar</mainClass>