Merge remote-tracking branch 'upstream/master'

.travis.yml

@@ -4,7 +4,7 @@ before_install:
   - echo "MAVEN_OPTS='-Xmx2048M -Xss128M -XX:+CMSClassUnloadingEnabled -XX:+UseG1GC -XX:-UseGCOverheadLimit'" > ~/.mavenrc
 
 install: skip
-script: travis_wait 60 mvn -q test
+script: travis_wait 60 mvn -q install
 
 sudo: required
 

README.md

@@ -17,6 +17,10 @@ This project is **a collection of small and focused tutorials** each covering a
 Most of the tutorial projects are focused on the `Spring Framework` (and `Spring Security`).  
 In additional to Spring, the following technologies are in focus: `core Java`, `Jackson`, `HttpClient`, `Guava`. 
 
+Building the project
+====================
+To do the full build, do: `mvn install -Dgib.enabled=false`
+
 
 Working with the code in Eclipse
 ================================
@@ -29,3 +33,10 @@ Any IDE can be used to work with the projects, but if you're using Eclipse, cons
 CI - Jenkins
 ================================
 This tutorials project is being built **[>> HERE](https://rest-security.ci.cloudbees.com/job/tutorials-unit/)**
+
+### Relevant Articles: 
+================================
+
+- [Apache Maven Standard Directory Layout](http://www.baeldung.com/maven-directory-structure)
+- [Apache Maven Tutorial](http://www.baeldung.com/maven)
+- [Designing a User Friendly Java Library](http://www.baeldung.com/design-a-user-friendly-java-library)

algorithms/README.md

@@ -21,3 +21,4 @@
 - [Create a Sudoku Solver in Java](http://www.baeldung.com/java-sudoku)
 - [Displaying Money Amounts in Words](http://www.baeldung.com/java-money-into-words)
 - [A Collaborative Filtering Recommendation System in Java](http://www.baeldung.com/java-collaborative-filtering-recommendations)
+- [Find All Pairs of Numbers in an Array That Add Up to a Given Sum](http://www.baeldung.com/java-algorithm-number-pairs-sum)

apache-opennlp/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles
+
+- [Intro to Apache OpenNLP](http://www.baeldung.com/apache-open-nlp)

asciidoctor/README.md

@@ -2,3 +2,4 @@
 
 - [Introduction to Asciidoctor](http://www.baeldung.com/introduction-to-asciidoctor)
 - [Generating a Book with Asciidoctor](http://www.baeldung.com/asciidoctor-book)
+- [Introduction to Asciidoctor in Java](http://www.baeldung.com/asciidoctor)

autovalue/pom.xml

@@ -18,10 +18,29 @@
             <artifactId>auto-value</artifactId>
             <version>${auto-value.version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.google.auto.factory</groupId>
+            <artifactId>auto-factory</artifactId>
+            <version>${auto-factory.version}</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>com.google.guava</groupId>
+                    <artifactId>guava</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+
+        <dependency>
+            <groupId>com.google.inject</groupId>
+            <artifactId>guice</artifactId>
+            <version>${guice.version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
         <auto-value.version>1.3</auto-value.version>
+        <auto-factory.version>1.0-beta5</auto-factory.version>
+        <guice.version>4.2.0</guice.version>
     </properties>
 
 </project>

autovalue/src/main/java/com/baeldung/autofactory/App.java

@@ -0,0 +1,21 @@
+package com.baeldung.autofactory;
+
+import com.baeldung.autofactory.model.Camera;
+import com.baeldung.autofactory.model.Phone;
+import com.baeldung.autofactory.model.PhoneFactory;
+import com.baeldung.autofactory.modules.SonyCameraModule;
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+
+public class App {
+
+    public static void main(String[] args) {
+        PhoneFactory phoneFactory = new PhoneFactory(() -> new Camera("Unknown", "XXX"));
+        Phone simplePhone = phoneFactory.create("other parts");
+
+        Injector injector = Guice.createInjector(new SonyCameraModule());
+        PhoneFactory injectedFactory = injector.getInstance(PhoneFactory.class);
+        Phone xperia = injectedFactory.create("Xperia");
+    }
+
+}

autovalue/src/main/java/com/baeldung/autofactory/CustomStorage.java

@@ -0,0 +1,12 @@
+package com.baeldung.autofactory;
+
+import com.baeldung.autofactory.custom.SmartPhone;
+
+/**
+ * @author aiet
+ */
+public interface CustomStorage {
+
+    SmartPhone customROMInGB(int romSize);
+
+}

autovalue/src/main/java/com/baeldung/autofactory/custom/AbstractFactory.java

@@ -0,0 +1,10 @@
+package com.baeldung.autofactory.custom;
+
+/**
+ * @author aiet
+ */
+public abstract class AbstractFactory {
+
+    abstract CustomPhone newInstance(String brand);
+
+}

autovalue/src/main/java/com/baeldung/autofactory/custom/CustomPhone.java

@@ -0,0 +1,16 @@
+package com.baeldung.autofactory.custom;
+
+import com.google.auto.factory.AutoFactory;
+
+/**
+ * @author aiet
+ */
+@AutoFactory(extending = AbstractFactory.class)
+public class CustomPhone {
+
+    private final String brand;
+
+    public CustomPhone(String brand) {
+        this.brand = brand;
+    }
+}

autovalue/src/main/java/com/baeldung/autofactory/custom/SmartPhone.java

@@ -0,0 +1,18 @@
+package com.baeldung.autofactory.custom;
+
+import com.baeldung.autofactory.CustomStorage;
+import com.google.auto.factory.AutoFactory;
+
+/**
+ * @author aiet
+ */
+@AutoFactory(className = "SamsungFactory", allowSubclasses = true, implementing = CustomStorage.class)
+public class SmartPhone {
+
+    private int romSize;
+
+    public SmartPhone(int romSize) {
+        this.romSize = romSize;
+    }
+
+}

autovalue/src/main/java/com/baeldung/autofactory/model/Camera.java

@@ -0,0 +1,24 @@
+package com.baeldung.autofactory.model;
+
+/**
+ * @author aiet
+ */
+public class Camera {
+
+    private final String manufacturer;
+    private final String serial;
+
+    public Camera(String manufacturer, String serial) {
+        this.manufacturer = manufacturer;
+        this.serial = serial;
+    }
+
+    public String getManufacturer() {
+        return manufacturer;
+    }
+
+    public String getSerial() {
+        return serial;
+    }
+
+}

autovalue/src/main/java/com/baeldung/autofactory/model/ClassicPhone.java

@@ -0,0 +1,38 @@
+package com.baeldung.autofactory.model;
+
+import com.google.auto.factory.AutoFactory;
+import com.google.auto.factory.Provided;
+
+/**
+ * @author aiet
+ */
+public class ClassicPhone {
+
+    private final String dialpad;
+    private final String ringer;
+    private String otherParts;
+
+    @AutoFactory
+    public ClassicPhone(@Provided String dialpad, @Provided String ringer) {
+        this.dialpad = dialpad;
+        this.ringer = ringer;
+    }
+
+    @AutoFactory
+    public ClassicPhone(String otherParts) {
+        this("defaultDialPad", "defaultRinger");
+        this.otherParts = otherParts;
+    }
+
+    public String getDialpad() {
+        return dialpad;
+    }
+
+    public String getRinger() {
+        return ringer;
+    }
+
+    public String getOtherParts() {
+        return otherParts;
+    }
+}

autovalue/src/main/java/com/baeldung/autofactory/model/Phone.java

@@ -0,0 +1,34 @@
+package com.baeldung.autofactory.model;
+
+import com.google.auto.factory.AutoFactory;
+import com.google.auto.factory.Provided;
+
+import javax.inject.Named;
+
+/**
+ * @author aiet
+ */
+@AutoFactory
+public class Phone {
+
+    private Camera camera;
+    private String otherParts;
+
+    public Phone(@Provided @Named("Sony") Camera camera, String otherParts) {
+        this.camera = camera;
+        this.otherParts = otherParts;
+    }
+
+    /* required when used as a base class for AutoFactory */
+    public Phone() {
+    }
+
+    public Camera getCamera() {
+        return camera;
+    }
+
+    public String getOtherParts() {
+        return otherParts;
+    }
+
+}

autovalue/src/main/java/com/baeldung/autofactory/modules/SonyCameraModule.java

@@ -0,0 +1,22 @@
+package com.baeldung.autofactory.modules;
+
+import com.baeldung.autofactory.model.Camera;
+import com.google.inject.AbstractModule;
+import com.google.inject.Provides;
+
+import javax.inject.Named;
+
+/**
+ * @author aiet
+ */
+public class SonyCameraModule extends AbstractModule {
+
+    private static int SONY_CAMERA_SERIAL = 1;
+
+    @Named("Sony")
+    @Provides
+    Camera cameraProvider() {
+        return new Camera("Sony", String.format("%03d", SONY_CAMERA_SERIAL++));
+    }
+
+}

autovalue/src/main/java/com/baeldung/autofactory/provided/IntermediateAssembler.java

@@ -0,0 +1,22 @@
+package com.baeldung.autofactory.provided;
+
+import com.google.auto.factory.AutoFactory;
+import com.google.auto.factory.Provided;
+import javafx.scene.Camera;
+
+import javax.inject.Provider;
+
+/**
+ * @author aiet
+ */
+@AutoFactory
+public class IntermediateAssembler {
+
+    private final Provider<Camera> camera;
+    private final String otherParts;
+
+    public IntermediateAssembler(@Provided Provider<Camera> camera, String otherParts) {
+        this.camera = camera;
+        this.otherParts = otherParts;
+    }
+}

autovalue/src/main/java/com/baeldung/autofactory/provider/SonyCameraProvider.java

@@ -0,0 +1,18 @@
+package com.baeldung.autofactory.provider;
+
+import com.baeldung.autofactory.model.Camera;
+import com.google.inject.Provider;
+
+/**
+ * @author aiet
+ */
+public class SonyCameraProvider implements Provider<Camera> {
+
+    private static int sonyCameraSerial = 1;
+
+    @Override
+    public Camera get() {
+        return new Camera("Sony", String.format("%03d", sonyCameraSerial++));
+    }
+
+}

aws/README.md

@@ -5,4 +5,8 @@
 - [AWS Lambda With Java](http://www.baeldung.com/java-aws-lambda)
 - [Managing EC2 Instances in Java](http://www.baeldung.com/ec2-java)
 - [http://www.baeldung.com/aws-s3-multipart-upload](https://github.com/eugenp/tutorials/tree/master/aws)
+- [Multipart Uploads in Amazon S3 with Java](http://www.baeldung.com/aws-s3-multipart-upload)
+- [Integration Testing with a Local DynamoDB Instance](http://www.baeldung.com/dynamodb-local-integration-tests)
+- [Using the JetS3t Java Client With Amazon S3](http://www.baeldung.com/jets3t-amazon-s3)
+- [Managing Amazon SQS Queues in Java](http://www.baeldung.com/aws-queues-java)
 

cas/cas-secured-app/README.md

@@ -1,2 +1,3 @@
 ## Relevant articles:
 - [CAS SSO With Spring Security](http://www.baeldung.com/spring-security-cas-sso)
+- [Code Analysis with SonarQube](http://www.baeldung.com/sonar-qube)

cdi/pom.xml

@@ -8,16 +8,12 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-spring</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-spring</relativePath>
     </parent>
 
     <dependencies>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-core</artifactId>
-            <version>${spring.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-context</artifactId>

core-groovy/pom.xml

@@ -28,12 +28,6 @@
             <artifactId>groovy-sql</artifactId>
             <version>${groovy-sql.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <version>${junit.jupiter.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.junit.platform</groupId>
             <artifactId>junit-platform-runner</artifactId>

core-java-10/pom.xml

@@ -0,0 +1,45 @@
+<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>core-java-10</artifactId>
+	<packaging>jar</packaging>
+	<version>0.1.0-SNAPSHOT</version>
+	<name>core-java-10</name>
+	<url>http://maven.apache.org</url>
+
+	<parent>
+		<groupId>com.baeldung</groupId>
+		<artifactId>parent-modules</artifactId>
+		<version>1.0.0-SNAPSHOT</version>
+	</parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>${junit.version}</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>${maven-compiler-plugin.version}</version>
+				<configuration>
+					<source>${maven.compiler.source.version}</source>
+					<target>${maven.compiler.target.version}</target>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+	<properties>
+		<maven.compiler.source.version>10</maven.compiler.source.version>
+		<maven.compiler.target.version>10</maven.compiler.target.version>
+	</properties>
+
+</project>

core-java-10/src/main/java/com/baeldung/App.java

@@ -0,0 +1,13 @@
+package com.baeldung;
+
+/**
+ * Hello world!
+ *
+ */
+public class App 
+{
+    public static void main( String[] args )
+    {
+        System.out.println( "Hello World!" );
+    }
+}

core-java-10/src/test/java/com/baeldung/AppTest.java

@@ -0,0 +1,38 @@
+package com.baeldung;
+
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+
+/**
+ * Unit test for simple App.
+ */
+public class AppTest 
+    extends TestCase
+{
+    /**
+     * Create the test case
+     *
+     * @param testName name of the test case
+     */
+    public AppTest( String testName )
+    {
+        super( testName );
+    }
+
+    /**
+     * @return the suite of tests being tested
+     */
+    public static Test suite()
+    {
+        return new TestSuite( AppTest.class );
+    }
+
+    /**
+     * Rigourous Test :-)
+     */
+    public void testApp()
+    {
+        assertTrue( true );
+    }
+}

core-java-10/src/test/java/com/baeldung/java10/Java10FeaturesUnitTest.java

@@ -0,0 +1,61 @@
+package com.baeldung.java10;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class Java10FeaturesUnitTest {
+
+    private List<Integer> someIntList;
+    
+    @Before
+    public void setup() {
+        someIntList = new ArrayList<>();
+        
+        someIntList.add(1);
+        someIntList.add(2);
+        someIntList.add(3);
+    }
+
+    @Test
+    public void whenVarInitWithString_thenGetStringTypeVar() {
+        var message = "Hello, Java 10";
+        assertTrue(message instanceof String);
+    }
+
+    @Test
+    public void whenVarInitWithAnonymous_thenGetAnonymousType() {
+        var obj = new Object() {};
+        assertFalse(obj.getClass().equals(Object.class));
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenModifyCopyOfList_thenThrowsException() {
+        List<Integer> copyList = List.copyOf(someIntList);
+        copyList.add(4);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void whenModifyToUnmodifiableList_thenThrowsException() {
+        List<Integer> evenList = someIntList.stream()
+          .filter(i -> i % 2 == 0)
+          .collect(Collectors.toUnmodifiableList());
+        evenList.add(4);
+    }
+
+    @Test
+    public void whenListContainsInteger_OrElseThrowReturnsInteger() {
+        Integer firstEven = someIntList.stream()
+          .filter(i -> i % 2 == 0)
+          .findFirst()
+          .orElseThrow();
+        is(firstEven).equals(Integer.valueOf(2));
+    }
+}

core-java-11/pom.xml

@@ -0,0 +1,45 @@
+<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>core-java-11</artifactId>
+	<packaging>jar</packaging>
+	<version>0.1.0-SNAPSHOT</version>
+	<name>core-java-11</name>
+	<url>http://maven.apache.org</url>
+
+	<parent>
+		<groupId>com.baeldung</groupId>
+		<artifactId>parent-modules</artifactId>
+		<version>1.0.0-SNAPSHOT</version>
+	</parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>${junit.version}</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>${maven-compiler-plugin.version}</version>
+				<configuration>
+					<source>${maven.compiler.source.version}</source>
+					<target>${maven.compiler.target.version}</target>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+	<properties>
+		<maven.compiler.source.version>11</maven.compiler.source.version>
+		<maven.compiler.target.version>11</maven.compiler.target.version>
+	</properties>
+
+</project>

core-java-11/src/main/java/com/baeldung/App.java

@@ -0,0 +1,13 @@
+package com.baeldung;
+
+/**
+ * Hello world!
+ *
+ */
+public class App 
+{
+    public static void main( String[] args )
+    {
+        System.out.println( "Hello World!" );
+    }
+}

core-java-11/src/test/java/com/baeldung/AppTest.java

@@ -0,0 +1,38 @@
+package com.baeldung;
+
+import junit.framework.Test;
+import junit.framework.TestCase;
+import junit.framework.TestSuite;
+
+/**
+ * Unit test for simple App.
+ */
+public class AppTest 
+    extends TestCase
+{
+    /**
+     * Create the test case
+     *
+     * @param testName name of the test case
+     */
+    public AppTest( String testName )
+    {
+        super( testName );
+    }
+
+    /**
+     * @return the suite of tests being tested
+     */
+    public static Test suite()
+    {
+        return new TestSuite( AppTest.class );
+    }
+
+    /**
+     * Rigourous Test :-)
+     */
+    public void testApp()
+    {
+        assertTrue( true );
+    }
+}

core-java-8/README.md

@@ -44,3 +44,10 @@
 - [Java 8 StringJoiner](http://www.baeldung.com/java-string-joiner)
 - [Introduction to Spliterator in Java](http://www.baeldung.com/java-spliterator)
 - [Java 8 Math New Methods](http://www.baeldung.com/java-8-math)
+- [Overview of Java Built-in Annotations](http://www.baeldung.com/java-default-annotations)
+- [Finding Min/Max in an Array with Java](http://www.baeldung.com/java-array-min-max)
+- [Internationalization and Localization in Java 8](http://www.baeldung.com/java-8-localization)
+- [Filtering Kotlin Collections](http://www.baeldung.com/kotlin-filter-collection)
+- [How to Find an Element in a List with Java](http://www.baeldung.com/find-list-element-java)
+- [Measure Elapsed Time in Java](http://www.baeldung.com/java-measure-elapsed-time)
+

core-java-8/pom.xml

@@ -9,17 +9,12 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
-        <!-- utils -->
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>

core-java-8/src/main/java/com/baeldung/findanelement/Customer.java

@@ -0,0 +1,37 @@
+package com.baeldung.findanelement;
+
+public class Customer {
+
+    private int id;
+    private String name;
+
+    public Customer(int id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    @Override
+    public int hashCode() {
+        return id * 20;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj instanceof Customer) {
+            Customer otherCustomer = (Customer) obj;
+            if (id == otherCustomer.id)
+                return true;
+        }
+        return false;
+    }
+
+
+}

core-java-8/src/main/java/com/baeldung/findanelement/FindACustomerInGivenList.java

@@ -0,0 +1,77 @@
+package com.baeldung.findanelement;
+
+import java.util.Iterator;
+import java.util.List;
+
+import org.apache.commons.collections4.IterableUtils;
+
+import com.google.common.base.Predicate;
+import com.google.common.collect.Iterables;
+
+public class FindACustomerInGivenList {
+
+    public Customer findUsingGivenIndex(int indexOfCustomer, List<Customer> customers) {
+        if (indexOfCustomer >= 0 && indexOfCustomer < customers.size())
+            return customers.get(indexOfCustomer);
+        return null;
+    }
+
+    public int findUsingIndexOf(Customer customer, List<Customer> customers) {
+        return customers.indexOf(customer);
+    }
+
+    public boolean findUsingContains(Customer customer, List<Customer> customers) {
+        return customers.contains(customer);
+    }
+
+    public Customer findUsingIterator(String name, List<Customer> customers) {
+        Iterator<Customer> iterator = customers.iterator();
+        while (iterator.hasNext()) {
+            Customer customer = iterator.next();
+            if (customer.getName().equals(name)) {
+                return customer;
+            }
+        }
+        return null;
+    }
+
+    public Customer findUsingEnhancedForLoop(String name, List<Customer> customers) {
+        for (Customer customer : customers) {
+            if (customer.getName().equals(name)) {
+                return customer;
+            }
+        }
+        return null;
+    }
+
+    public Customer findUsingStream(String name, List<Customer> customers) {
+        return customers.stream()
+            .filter(customer -> customer.getName().equals(name))
+            .findFirst()
+            .orElse(null);
+    }
+
+    public Customer findUsingParallelStream(String name, List<Customer> customers) {
+        return customers.parallelStream()
+            .filter(customer -> customer.getName().equals(name))
+            .findAny()
+            .orElse(null);
+    }
+
+    public Customer findUsingGuava(String name, List<Customer> customers) {
+        return Iterables.tryFind(customers, new Predicate<Customer>() {
+            public boolean apply(Customer customer) {
+                return customer.getName().equals(name);
+            }
+        }).orNull();
+    }
+
+    public Customer findUsingApacheCommon(String name, List<Customer> customers) {
+        return IterableUtils.find(customers, new org.apache.commons.collections4.Predicate<Customer>() {
+            public boolean evaluate(Customer customer) {
+                return customer.getName().equals(name);
+            }
+        });
+    }
+
+}

core-java-8/src/main/java/com/baeldung/findanelement/FindElementInAList.java

@@ -1,71 +0,0 @@
-package com.baeldung.findanelement;
-
-import java.util.List;
-import java.util.ListIterator;
-import org.apache.commons.collections4.IterableUtils;
-import com.google.common.base.Predicate;
-import com.google.common.collect.Iterables;
-
-public class FindElementInAList<T> {
-
-    public T findUsingIndexOf(T element, List<T> list) {
-        int index = list.indexOf(element);
-        if (index >= 0) {
-            return element;
-        }
-        return null;
-    }
-
-    public boolean findUsingListIterator(T element, List<T> list) {
-        ListIterator<T> listIterator = list.listIterator();
-        while (listIterator.hasNext()) {
-            T elementFromList = listIterator.next();
-            if (elementFromList.equals(element)) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    public boolean findUsingEnhancedForLoop(T element, List<T> list) {
-        for (T elementFromList : list) {
-            if (element.equals(elementFromList)) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    public T findUsingStream(T element, List<T> list) {
-        return list.stream()
-            .filter(integer -> integer.equals(element))
-            .findFirst()
-            .orElse(null);
-    }
-
-    public T findUsingParallelStream(T element, List<T> list) {
-        return list.parallelStream()
-            .filter(integer -> integer.equals(element))
-            .findAny()
-            .orElse(null);
-    }
-
-    public T findUsingGuava(T element, List<T> list) {
-        T foundElement = Iterables.tryFind(list, new Predicate<T>() {
-            public boolean apply(T input) {
-                return element.equals(input);
-            }
-        }).orNull();
-        return foundElement;
-    }
-
-    public T findUsingApacheCommon(T element, List<T> list) {
-        T foundElement = IterableUtils.find(list, new org.apache.commons.collections4.Predicate<T>() {
-            public boolean evaluate(T input) {
-                return element.equals(input);
-            }
-        });
-        return foundElement;
-    }
-
-}

core-java-8/src/test/java/com/baeldung/findanelement/FindACustomerInGivenListTest.java

@@ -0,0 +1,158 @@
+package com.baeldung.findanelement;
+
+import static org.junit.Assert.*;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Test;
+
+public class FindACustomerInGivenListTest {
+
+    private static List<Customer> customers = new ArrayList<>();
+
+    static {
+        customers.add(new Customer(1, "Jack"));
+        customers.add(new Customer(2, "James"));
+        customers.add(new Customer(3, "Sam"));
+    }
+
+    private static FindACustomerInGivenList findACustomerInGivenList = new FindACustomerInGivenList();
+
+    @Test
+    public void givenAnIndex_whenFoundUsingGivenIndex_thenReturnCustomer() {
+        Customer customer = findACustomerInGivenList.findUsingGivenIndex(0, customers);
+
+        assertEquals(1, customer.getId());
+    }
+
+    @Test
+    public void givenAnIndex_whenNotFoundUsingGivenIndex_thenReturnNull() {
+        Customer customer = findACustomerInGivenList.findUsingGivenIndex(5, customers);
+
+        assertNull(customer);
+    }
+
+    @Test
+    public void givenACustomer_whenFoundUsingContains_thenReturnTrue() {
+        Customer james = new Customer(2, "James");
+        boolean isJamesPresent = findACustomerInGivenList.findUsingContains(james, customers);
+
+        assertEquals(true, isJamesPresent);
+    }
+
+    @Test
+    public void givenACustomer_whenNotFoundUsingContains_thenReturnFalse() {
+        Customer john = new Customer(5, "John");
+        boolean isJohnPresent = findACustomerInGivenList.findUsingContains(john, customers);
+
+        assertEquals(false, isJohnPresent);
+    }
+
+    @Test
+    public void givenACustomer_whenFoundUsingIndexOf_thenReturnItsIndex() {
+        Customer james = new Customer(2, "James");
+        int indexOfJames = findACustomerInGivenList.findUsingIndexOf(james, customers);
+
+        assertEquals(1, indexOfJames);
+    }
+
+    @Test
+    public void givenACustomer_whenNotFoundUsingIndexOf_thenReturnMinus1() {
+        Customer john = new Customer(5, "John");
+        int indexOfJohn = findACustomerInGivenList.findUsingIndexOf(john, customers);
+
+        assertEquals(-1, indexOfJohn);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingIterator_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingIterator("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingIterator_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingIterator("John", customers);
+
+        assertNull(john);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingEnhancedFor_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingEnhancedForLoop("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingEnhancedFor_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingEnhancedForLoop("John", customers);
+
+        assertNull(john);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingStream_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingStream("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingStream_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingStream("John", customers);
+
+        assertNull(john);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingParallelStream_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingParallelStream("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingParallelStream_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingParallelStream("John", customers);
+
+        assertNull(john);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingApacheCommon_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingApacheCommon("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingApacheCommon_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingApacheCommon("John", customers);
+
+        assertNull(john);
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameFoundUsingGuava_thenReturnCustomer() {
+        Customer james = findACustomerInGivenList.findUsingGuava("James", customers);
+
+        assertEquals("James", james.getName());
+        assertEquals(2, james.getId());
+    }
+
+    @Test
+    public void givenName_whenCustomerWithNameNotFoundUsingGuava_thenReturnNull() {
+        Customer john = findACustomerInGivenList.findUsingGuava("John", customers);
+
+        assertNull(john);
+    }
+
+}

core-java-8/src/test/java/com/baeldung/findanelement/FindAnElementTest.java

@@ -1,116 +0,0 @@
-package com.baeldung.findanelement;
-
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
-import java.util.ArrayList;
-import java.util.List;
-import org.junit.Test;
-
-public class FindAnElementTest {
-
-    private static List<Integer> scores = new ArrayList<>();
-    static {
-        scores.add(0);
-        scores.add(1);
-        scores.add(2);
-    }
-
-    private static FindElementInAList<Integer> findElementInAList = new FindElementInAList<>();
-
-    @Test
-    public void givenElement_whenFoundUsingIndexOf_thenReturnElement() {
-        Integer scoreToFind = 1;
-        Integer score = findElementInAList.findUsingIndexOf(scoreToFind, scores);
-        assertTrue(score.equals(scoreToFind));
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingListIterator_thenReturnNull() {
-        boolean found = findElementInAList.findUsingListIterator(5, scores);
-        assertTrue(!found);
-    }
-    
-    @Test
-    public void givenElement_whenFoundListIterator_thenReturnElement() {
-        Integer scoreToFind = 1;
-        boolean found = findElementInAList.findUsingListIterator(scoreToFind, scores);
-        assertTrue(found);
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingIndexOf_thenReturnNull() {
-        Integer score = findElementInAList.findUsingIndexOf(5, scores);
-        assertNull(score);
-    }
-
-    @Test
-    public void givenElement_whenFoundUsingEnhancedForLoop_thenReturnElement() {
-        Integer scoreToFind = 1;
-        boolean found = findElementInAList.findUsingEnhancedForLoop(scoreToFind, scores);
-        assertTrue(found);
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingEnhancedForLoop_thenReturnNull() {
-        Integer scoreToFind = 5;
-        boolean found = findElementInAList.findUsingEnhancedForLoop(scoreToFind, scores);
-        assertTrue(!found);
-    }
-
-    @Test
-    public void givenElement_whenFoundUsingStream_thenReturnElement() {
-        Integer scoreToFind = 1;
-        Integer score = findElementInAList.findUsingStream(scoreToFind, scores);
-        assertTrue(score.equals(scoreToFind));
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingStream_thenReturnNull() {
-        Integer scoreToFind = 5;
-        Integer score = findElementInAList.findUsingStream(scoreToFind, scores);
-        assertNull(score);
-    }
-
-    @Test
-    public void givenElement_whenFoundUsingParallelStream_thenReturnElement() {
-        Integer scoreToFind = 1;
-        Integer score = findElementInAList.findUsingParallelStream(scoreToFind, scores);
-        assertTrue(score.equals(scoreToFind));
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingParallelStream_thenReturnNull() {
-        Integer scoreToFind = 5;
-        Integer score = findElementInAList.findUsingParallelStream(scoreToFind, scores);
-        assertNull(score);
-    }
-
-    @Test
-    public void givenElement_whenFoundUsingGuava_thenReturnElement() {
-        Integer scoreToFind = 1;
-        Integer score = findElementInAList.findUsingGuava(scoreToFind, scores);
-        assertTrue(score.equals(scoreToFind));
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingGuava_thenReturnNull() {
-        Integer scoreToFind = 5;
-        Integer score = findElementInAList.findUsingGuava(scoreToFind, scores);
-        assertNull(score);
-    }
-
-    @Test
-    public void givenElement_whenFoundUsingApacheCommons_thenReturnElement() {
-        Integer scoreToFind = 1;
-        Integer score = findElementInAList.findUsingApacheCommon(scoreToFind, scores);
-        assertTrue(score.equals(scoreToFind));
-    }
-
-    @Test
-    public void givenElement_whenNotFoundUsingApacheCommons_thenReturnNull() {
-        Integer scoreToFind = 5;
-        Integer score = findElementInAList.findUsingApacheCommon(scoreToFind, scores);
-        assertNull(score);
-    }
-
-}

core-java-9/README.md

@@ -23,3 +23,4 @@
 - [Exploring the New HTTP Client in Java 9](http://www.baeldung.com/java-9-http-client)
 - [Method Handles in Java](http://www.baeldung.com/java-method-handles)
 - [Introduction to Chronicle Queue](http://www.baeldung.com/java-chronicle-queue)
+- [A Guide to Java 9 Modularity](http://www.baeldung.com/java-9-modularity)

core-java-collections/README.md

@@ -0,0 +1,30 @@
+=========
+
+## Core Java Collections Cookbooks and Examples
+
+### Relevant Articles: 
+- [Immutable ArrayList in Java](http://www.baeldung.com/java-immutable-list)
+- [Converting between an Array and a List in Java](http://www.baeldung.com/convert-array-to-list-and-list-to-array)
+- [Converting between an Array and a Set in Java](http://www.baeldung.com/convert-array-to-set-and-set-to-array)
+- [Converting between a List and a Set in Java](http://www.baeldung.com/convert-list-to-set-and-set-to-list)
+- [Convert a Map to an Array, List or Set in Java](http://www.baeldung.com/convert-map-values-to-array-list-set)
+- [Guide to the Java ArrayList](http://www.baeldung.com/java-arraylist)
+- [Random List Element](http://www.baeldung.com/java-random-list-element)
+- [Java - Combine Multiple Collections](http://www.baeldung.com/java-combine-multiple-collections)
+- [Guide to WeakHashMap in Java](http://www.baeldung.com/java-weakhashmap)
+- [Guide to the Guava BiMap](http://www.baeldung.com/guava-bimap)
+- [The Java HashMap Under the Hood](http://www.baeldung.com/java-hashmap)
+- [A Guide to LinkedHashMap in Java](http://www.baeldung.com/java-linked-hashmap)
+- [A Guide to TreeMap in Java](http://www.baeldung.com/java-treemap)
+- [Removing all nulls from a List in Java](http://www.baeldung.com/java-remove-nulls-from-list)
+- [Removing all duplicates from a List in Java](http://www.baeldung.com/java-remove-duplicates-from-list)
+- [Flattening Nested Collections in Java](http://www.baeldung.com/java-flatten-nested-collections)
+- [HashSet and TreeSet Comparison](http://www.baeldung.com/java-hashset-vs-treeset)
+- [Iterate over a Map in Java](http://www.baeldung.com/java-iterate-map)
+- [Collect a Java Stream to an Immutable Collection](http://www.baeldung.com/java-stream-immutable-collection)
+- [Converting a List to String in Java](http://www.baeldung.com/java-list-to-string)
+- [Introduction to the Java ArrayDeque](http://www.baeldung.com/java-array-deque)
+- [A Guide to HashSet in Java](http://www.baeldung.com/java-hashset)
+- [A Guide to TreeSet in Java](http://www.baeldung.com/java-tree-set)
+- [Java TreeMap vs HashMap](http://www.baeldung.com/java-treemap-vs-hashmap)
+- [How to TDD a List Implementation in Java](http://www.baeldung.com/java-test-driven-list)

core-java-collections/pom.xml

@@ -0,0 +1,60 @@
+<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>core-java-collections</artifactId>
+	<version>0.1.0-SNAPSHOT</version>
+	<packaging>jar</packaging>
+	<name>core-java-collections</name>
+
+	<parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
+    </parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<version>${junit.version}</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>net.sourceforge.collections</groupId>
+			<artifactId>collections-generic</artifactId>
+			<version>${collections-generic.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.commons</groupId>
+			<artifactId>commons-collections4</artifactId>
+			<version>${commons-collections4.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>com.jayway.awaitility</groupId>
+			<artifactId>awaitility</artifactId>
+			<version>${avaitility.version}</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.commons</groupId>
+			<artifactId>commons-lang3</artifactId>
+			<version>${commons-lang3.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.assertj</groupId>
+			<artifactId>assertj-core</artifactId>
+			<version>${assertj.version}</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<properties>
+		<commons-lang3.version>3.5</commons-lang3.version>
+		<commons-collections4.version>4.1</commons-collections4.version>
+		<collections-generic.version>4.01</collections-generic.version>
+		<avaitility.version>1.7.0</avaitility.version>
+		<assertj.version>3.6.1</assertj.version>
+	</properties>
+</project>

core-java-collections/src/test/java/com/baeldung/java/map/MapMultipleValuesTest.java

@@ -0,0 +1,124 @@
+package com.baeldung.java.map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.commons.collections4.MultiMap;
+import org.apache.commons.collections4.MultiMapUtils;
+import org.apache.commons.collections4.MultiValuedMap;
+import org.apache.commons.collections4.map.MultiValueMap;
+import org.apache.commons.collections4.multimap.ArrayListValuedHashMap;
+import org.apache.commons.collections4.multimap.HashSetValuedHashMap;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.LinkedHashMultimap;
+import com.google.common.collect.Multimap;
+import com.google.common.collect.TreeMultimap;
+
+public class MapMultipleValuesTest {
+    private static final Logger LOG = LoggerFactory.getLogger(MapMultipleValuesTest.class);
+
+    @Test
+    public void givenHashMap_whenPuttingTwice_thenReturningFirstValue() {
+        Map<String, String> map = new HashMap<>();
+        assertThat(map.put("key1", "value1")).isEqualTo(null);
+        assertThat(map.put("key1", "value2")).isEqualTo("value1");
+        assertThat(map.get("key1")).isEqualTo("value2");
+    }
+
+    @Test
+    public void givenCollectionAsValue_whenPuttingTwice_thenReturningCollection() {
+        Map<String, List<String>> map = new HashMap<>();
+        List<String> list = new ArrayList<>();
+        map.put("key1", list);
+        map.get("key1").add("value1");
+        map.get("key1").add("value2");
+        assertThat(map.get("key1").get(0)).isEqualTo("value1");
+        assertThat(map.get("key1").get(1)).isEqualTo("value2");
+    }
+
+    @Test
+    public void givenCollectionAsValueAndJava8_whenPuttingTwice_thenReturningCollection() {
+        Map<String, List<String>> map = new HashMap<>();
+        map.computeIfAbsent("key1", k -> new ArrayList<>()).add("value1");
+        map.computeIfAbsent("key1", k -> new ArrayList<>()).add("value2");
+        assertThat(map.get("key1").get(0)).isEqualTo("value1");
+        assertThat(map.get("key1").get(1)).isEqualTo("value2");
+    }
+
+    @Test
+    public void givenMultiValueMap_whenPuttingTwice_thenReturningValues() {
+        MultiMap<String, String> map = new MultiValueMap<>();
+        map.put("key1", "value1");
+        map.put("key1", "value2");
+        assertThat((Collection<String>) map.get("key1"))
+          .contains("value1", "value2");
+    }
+
+    @Test
+    public void givenArrayListValuedHashMap_whenPuttingDoubleValues_thenReturningAllValues() {
+        MultiValuedMap<String, String> map = new ArrayListValuedHashMap<>();
+        map.put("key1", "value1");
+        map.put("key1", "value2");
+        map.put("key1", "value2");
+        assertThat((Collection<String>) map.get("key1"))
+          .containsExactly("value1", "value2", "value2");
+    }
+    
+    @Test
+    public void givenHashSetValuedHashMap_whenPuttingTwiceTheSame_thenReturningOneValue() {
+        MultiValuedMap<String, String> map = new HashSetValuedHashMap<>();
+        map.put("key1", "value1");
+        map.put("key1", "value1");
+        assertThat((Collection<String>) map.get("key1"))
+          .containsExactly("value1");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void givenUnmodifiableMultiValuedMap_whenInserting_thenThrowingException() {
+        MultiValuedMap<String, String> map = new ArrayListValuedHashMap<>();
+        map.put("key1", "value1");
+        map.put("key1", "value2");
+        MultiValuedMap<String, String> immutableMap =
+          MultiMapUtils.unmodifiableMultiValuedMap(map);
+        immutableMap.put("key1", "value3");
+    }
+    
+    @Test
+    public void givenArrayListMultiMap_whenInserting_thenCorrectOutput() {
+        Multimap<String, String> map = ArrayListMultimap.create();
+        map.put("key1", "value2");
+        map.put("key1", "value1");
+        assertThat((Collection<String>) map.get("key1"))
+          .containsExactly("value2", "value1");
+    }   
+    
+    @Test
+    public void givenLinkedHashMultiMap_whenInserting_thenReturningValuesInInsertionOrder() {
+        Multimap<String, String> map = LinkedHashMultimap.create();
+        map.put("key1", "value3");
+        map.put("key1", "value1");
+        map.put("key1", "value2");
+        assertThat((Collection<String>) map.get("key1"))
+          .containsExactly("value3", "value1", "value2");
+    }
+
+    @Test
+    public void givenTreeMultimap_whenInserting_thenReturningValuesInNaturalOrder() {
+        Multimap<String, String> map = TreeMultimap.create();
+        map.put("key1", "value3");
+        map.put("key1", "value1");
+        map.put("key1", "value2");
+        assertThat((Collection<String>) map.get("key1"))
+          .containsExactly("value1", "value2", "value3");
+    }
+    
+}

core-java-concurrency/pom.xml

@@ -9,17 +9,12 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
-        <!-- utils -->
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>

core-java-io/README.md

@@ -25,3 +25,5 @@
 - [Zipping and Unzipping in Java](http://www.baeldung.com/java-compress-and-uncompress)
 - [Java NIO2 Path API](http://www.baeldung.com/java-nio-2-path)
 - [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)
+- [A Guide to NIO2 Asynchronous Socket Channel](http://www.baeldung.com/java-nio2-async-socket-channel)

core-java-io/pom.xml

@@ -9,8 +9,9 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
@@ -20,11 +21,6 @@
             <artifactId>collections-generic</artifactId>
             <version>${collections-generic.version}</version>
         </dependency>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>

core-java-sun/pom.xml

@@ -8,8 +8,9 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
@@ -19,11 +20,6 @@
             <artifactId>collections-generic</artifactId>
             <version>${collections-generic.version}</version>
         </dependency>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>

core-java/README.md

@@ -3,21 +3,14 @@
 ## Core Java Cookbooks and Examples
 
 ### Relevant Articles: 
-- [Immutable ArrayList in Java](http://www.baeldung.com/java-immutable-list)
-- [Converting between an Array and a List in Java](http://www.baeldung.com/convert-array-to-list-and-list-to-array)
-- [Converting between an Array and a Set in Java](http://www.baeldung.com/convert-array-to-set-and-set-to-array)
-- [Converting between a List and a Set in Java](http://www.baeldung.com/convert-list-to-set-and-set-to-list)
-- [Convert a Map to an Array, List or Set in Java](http://www.baeldung.com/convert-map-values-to-array-list-set)
 - [Java – Random Long, Float, Integer and Double](http://www.baeldung.com/java-generate-random-long-float-integer-double)
 - [Java – Generate Random String](http://www.baeldung.com/java-random-string)
 - [Java Timer](http://www.baeldung.com/java-timer-and-timertask)
 - [How to Run a Shell Command in Java](http://www.baeldung.com/run-shell-command-in-java)
 - [MD5 Hashing in Java](http://www.baeldung.com/java-md5)
-- [Guide to the Java ArrayList](http://www.baeldung.com/java-arraylist)
 - [Guide to Java Reflection](http://www.baeldung.com/java-reflection)
 - [A Guide to Java Sockets](http://www.baeldung.com/a-guide-to-java-sockets)
 - [Convert char to String in Java](http://www.baeldung.com/java-convert-char-to-string)
-- [Random List Element](http://www.baeldung.com/java-random-list-element)
 - [Convert String to int or Integer in Java](http://www.baeldung.com/java-convert-string-to-int-or-integer)
 - [Java – Try with Resources](http://www.baeldung.com/java-try-with-resources)
 - [Guide to the Fork/Join Framework in Java](http://www.baeldung.com/java-fork-join)
@@ -29,7 +22,6 @@
 - [Sorting in Java](http://www.baeldung.com/java-sorting)
 - [Getting Started with Java Properties](http://www.baeldung.com/java-properties)
 - [Grep in Java](http://www.baeldung.com/grep-in-java)
-- [Java - Combine Multiple Collections](http://www.baeldung.com/java-combine-multiple-collections)
 - [Simulated Annealing for Travelling Salesman Problem](http://www.baeldung.com/java-simulated-annealing-for-traveling-salesman)
 - [Slope One Algorithm: Collaborative Filtering Recommendation Systems](http://www.baeldung.com/java-collaborative-filtering-recommendations)
 - [Pattern Search with Grep in Java](http://www.baeldung.com/grep-in-java)
@@ -38,28 +30,19 @@
 - [The Traveling Salesman Problem in Java](http://www.baeldung.com/java-simulated-annealing-for-traveling-salesman)
 - [How to Create an Executable JAR with Maven](http://www.baeldung.com/executable-jar-with-maven)
 - [How to Design a Genetic Algorithm in Java](http://www.baeldung.com/java-genetic-algorithm)
-- [Guide to WeakHashMap in Java](http://www.baeldung.com/java-weakhashmap)
 - [Spring Security – Cache Control Headers](http://www.baeldung.com/spring-security-cache-control-headers)
 - [Basic Introduction to JMX](http://www.baeldung.com/java-management-extensions)
 - [AWS Lambda With Java](http://www.baeldung.com/java-aws-lambda)
 - [Introduction to Nashorn](http://www.baeldung.com/java-nashorn)
-- [Guide to the Guava BiMap](http://www.baeldung.com/guava-bimap)
 - [Chained Exceptions in Java](http://www.baeldung.com/java-chained-exceptions)
-- [The Java HashMap Under the Hood](http://www.baeldung.com/java-hashmap)
-- [A Guide to LinkedHashMap in Java](http://www.baeldung.com/java-linked-hashmap)
-- [A Guide to TreeMap in Java](http://www.baeldung.com/java-treemap)
 - [A Quick JUnit vs TestNG Comparison](http://www.baeldung.com/junit-vs-testng)
 - [Java Primitive Conversions](http://www.baeldung.com/java-primitive-conversions)
 - [Java Money and the Currency API](http://www.baeldung.com/java-money-and-currency)
-- [Removing all nulls from a List in Java](http://www.baeldung.com/java-remove-nulls-from-list)
-- [Removing all duplicates from a List in Java](http://www.baeldung.com/java-remove-duplicates-from-list)
 - [Using Math.pow in Java](http://www.baeldung.com/java-math-pow)
 - [Converting Strings to Enums in Java](http://www.baeldung.com/java-string-to-enum)
-- [Flattening Nested Collections in Java](http://www.baeldung.com/java-flatten-nested-collections)
 - [Quick Guide to the Java StringTokenizer](http://www.baeldung.com/java-stringtokenizer)
 - [JVM Log Forging](http://www.baeldung.com/jvm-log-forging)
 - [Guide to sun.misc.Unsafe](http://www.baeldung.com/java-unsafe)
-- [HashSet and TreeSet Comparison](http://www.baeldung.com/java-hashset-vs-treeset)
 - [How to Perform a Simple HTTP Request in Java](http://www.baeldung.com/java-http-request)
 - [Call Methods at Runtime Using Java Reflection](http://www.baeldung.com/java-method-reflection)
 - [Guide to UUID in JAVA](http://www.baeldung.com/guide-to-uuid-in-java)
@@ -71,7 +54,6 @@
 - [How to Find all Getters Returning Null](http://www.baeldung.com/java-getters-returning-null)
 - [Changing the Order in a Sum Operation Can Produce Different Results?](http://www.baeldung.com/java-floating-point-sum-order)
 - [How to Get a Name of a Method Being Executed?](http://www.baeldung.com/java-name-of-executing-method)
-- [Iterate over a Map in Java](http://www.baeldung.com/java-iterate-map)
 - [Dynamic Proxies in Java](http://www.baeldung.com/java-dynamic-proxies)
 - [How to Copy an Array in Java](http://www.baeldung.com/java-array-copy)
 - [Introduction to JDBC](http://www.baeldung.com/java-jdbc)
@@ -87,10 +69,8 @@
 - [Guide to UUID in Java](http://www.baeldung.com/java-uuid)
 - [Guide to Escaping Characters in Java RegExps](http://www.baeldung.com/java-regexp-escape-char)
 - [Guide to hashCode() in Java](http://www.baeldung.com/java-hashcode)
-- [Collect a Java Stream to an Immutable Collection](http://www.baeldung.com/java-stream-immutable-collection)
 - [Difference between URL and URI](http://www.baeldung.com/java-url-vs-uri)
 - [Broadcasting and Multicasting in Java](http://www.baeldung.com/java-broadcast-multicast)
-- [Converting a List to String in Java](http://www.baeldung.com/java-list-to-string)
 - [CharSequence vs. String in Java](http://www.baeldung.com/java-char-sequence-string)
 - [Period and Duration in Java](http://www.baeldung.com/java-period-duration)
 - [Guide to the Diamond Operator in Java](http://www.baeldung.com/java-diamond-operator)
@@ -108,7 +88,6 @@
 - [Quick Example - Comparator vs Comparable in Java](http://www.baeldung.com/java-comparator-comparable)
 - [Quick Guide to Java Stack](http://www.baeldung.com/java-stack)
 - [The Java continue and break Keywords](http://www.baeldung.com/java-continue-and-break)
-- [Introduction to the Java ArrayDeque](http://www.baeldung.com/java-array-deque)
 - [Guide to java.util.Formatter](http://www.baeldung.com/java-string-formatter)
 - [Batch Processing in JDBC](http://www.baeldung.com/jdbc-batch-processing)
 - [Check if a Java Array Contains a Value](http://www.baeldung.com/java-array-contains-value)
@@ -122,34 +101,48 @@
 - [Nested Classes in Java](http://www.baeldung.com/java-nested-classes)
 - [A Guide to Java Loops](http://www.baeldung.com/java-loops)
 - [Varargs in Java](http://www.baeldung.com/java-varargs)
-- [A Guide to HashSet in Java](http://www.baeldung.com/java-hashset)
 - [A Guide to Inner Interfaces in Java](http://www.baeldung.com/java-inner-interfaces)
 - [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)
-- [A Guide to TreeSet in Java](http://www.baeldung.com/java-tree-set)
 - [Guide to ThreadLocalRandom in Java](http://www.baeldung.com/java-thread-local-random)
-- [Java TreeMap vs HashMap](http://www.baeldung.com/java-treemap-vs-hashmap)
 - [A Guide to Iterator in Java](http://www.baeldung.com/java-iterator)
 - [The Trie Data Structure in Java](http://www.baeldung.com/trie-java)
 - [Introduction to Javadoc](http://www.baeldung.com/javadoc)
-- [How to TDD a List Implementation](http://jira.baeldung.com/browse/BAEL-1537)
 - [How to Make a Deep Copy of an Object in Java](http://www.baeldung.com/java-deep-copy)
 - [Check if a String is a Palindrome](http://www.baeldung.com/java-palindrome)
 - [Comparing Strings in Java](http://www.baeldung.com/java-compare-strings)
 - [Guide to Inheritance in Java](http://www.baeldung.com/java-inheritance)
 - [Guide to Externalizable Interface in Java](http://www.baeldung.com/java-externalizable)
-- [The Observer Pattern in Java](https://github.com/eugenp/tutorials/tree/master/core-java)
+- [The Observer Pattern in Java](http://www.baeldung.com/java-observer-pattern)
 - [Flyweight Pattern in Java](http://www.baeldung.com/java-flyweight)
 - [Object Type Casting in Java](http://www.baeldung.com/java-type-casting)
 - [A Practical Guide to DecimalFormat](http://www.baeldung.com/java-decimalformat)
 - [How to Detect the OS Using Java](http://www.baeldung.com/java-detect-os)
-- [How to TDD a List Implementation in Java](http://www.baeldung.com/java-test-driven-list)
 - [ASCII Art in Java](http://www.baeldung.com/ascii-art-in-java)
 - [An Advanced Tagging Implementation with JPA](http://www.baeldung.com/jpa-tagging-advanced)
 - [Handling Daylight Savings Time in Java](http://www.baeldung.com/java-daylight-savings)
 - [Inheritance and Composition (Is-a vs Has-a relationship) in Java](http://www.baeldung.com/java-inheritance-composition)
 - [Finding Max/Min of a List or Collection](http://www.baeldung.com/java-collection-min-max)
 - [The "final" Keyword in Java](http://www.baeldung.com/java-final)
+- [What is the serialVersionUID?](http://www.baeldung.com/java-serial-version-uid)
+- [A Guide To UDP In Java](http://www.baeldung.com/udp-in-java)
+- [A Guide to the Java LinkedList](http://www.baeldung.com/java-linkedlist)
+- [A Guide to Java Enums](http://www.baeldung.com/a-guide-to-java-enums)
+- [A Guide to the ResourceBundle](http://www.baeldung.com/java-resourcebundle)
+- [Quick Guide to java.lang.System](http://www.baeldung.com/java-lang-system)
+- [Class Loaders in Java](http://www.baeldung.com/java-classloaders)
+- [Find Sum and Average in a Java Array](http://www.baeldung.com/java-array-sum-average)
+- [Java List UnsupportedOperationException](http://www.baeldung.com/java-list-unsupported-operation-exception)
+- [Service Locator Pattern](http://www.baeldung.com/java-service-locator-pattern)
+- [Type Erasure in Java Explained](http://www.baeldung.com/java-type-erasure)
+- [BigDecimal and BigInteger in Java](http://www.baeldung.com/java-bigdecimal-biginteger)
+- [Display All Time Zones With GMT And UTC in Java](http://www.baeldung.com/java-time-zones)
+- [Join and Split Arrays and Collections in Java](http://www.baeldung.com/java-join-and-split)
+- [Check If Two Lists are Equal in Java](http://www.baeldung.com/java-test-a-list-for-ordinality-and-equality)
+- [Sending Emails with Java](http://www.baeldung.com/java-email)
+- [Introduction to SSL in Java](http://www.baeldung.com/java-ssl)
+- [Java KeyStore API](http://www.baeldung.com/java-keystore)
+- [Double-Checked Locking with Singleton](http://www.baeldung.com/java-singleton-double-checked-locking)

core-java/pom.xml

@@ -9,27 +9,12 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
-        <!-- utils -->
-        <dependency>
-            <groupId>net.sourceforge.collections</groupId>
-            <artifactId>collections-generic</artifactId>
-            <version>${collections-generic.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-collections4</artifactId>
-            <version>${commons-collections4.version}</version>
-        </dependency>
         <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>
@@ -148,12 +133,6 @@
             <version>${mockito.version}</version>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>com.jayway.awaitility</groupId>
-            <artifactId>awaitility</artifactId>
-            <version>${avaitility.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>commons-codec</groupId>
             <artifactId>commons-codec</artifactId>
@@ -454,15 +433,12 @@
         <log4j.version>1.2.17</log4j.version>
 
         <!-- util -->
-        <guava.version>22.0</guava.version>
         <commons-lang3.version>3.5</commons-lang3.version>
         <bouncycastle.version>1.55</bouncycastle.version>
         <commons-codec.version>1.10</commons-codec.version>
         <commons-math3.version>3.6.1</commons-math3.version>
         <decimal4j.version>1.0.3</decimal4j.version>
         <commons-io.version>2.5</commons-io.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
-        <collections-generic.version>4.01</collections-generic.version>
         <unix4j.version>0.4</unix4j.version>
         <grep4j.version>1.8.7</grep4j.version>
         <lombok.version>1.16.12</lombok.version>
@@ -475,7 +451,6 @@
         <org.hamcrest.version>1.3</org.hamcrest.version>
         <mockito.version>2.8.9</mockito.version>
         <assertj.version>3.6.1</assertj.version>
-        <avaitility.version>1.7.0</avaitility.version>
 
         <!-- maven plugins -->
         <maven-compiler-plugin.version>3.7.0</maven-compiler-plugin.version>

core-kotlin/README.md

@@ -25,3 +25,4 @@
 - [Objects in Kotlin](http://www.baeldung.com/kotlin-objects)
 - [Reading from a File in Kotlin](http://www.baeldung.com/kotlin-read-file)
 - [Guide to Kotlin @JvmField](http://www.baeldung.com/kotlin-jvm-field-annotation)
+- [Filtering Kotlin Collections](http://www.baeldung.com/kotlin-filter-collection)

core-kotlin/pom.xml

@@ -25,12 +25,6 @@
             <artifactId>commons-math3</artifactId>
             <version>${commons-math3.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <version>${junit.jupiter.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.junit.platform</groupId>
             <artifactId>junit-platform-runner</artifactId>

core-kotlin/src/main/kotlin/com/baeldung/filesystem/FileWriter.kt

@@ -0,0 +1,19 @@
+package com.baeldung.filesystem
+
+import java.io.File
+
+class FileWriter {
+
+    fun writeFileUsingPrintWriter(fileName: String, fileContent: String) =
+            File(fileName).printWriter().use { out -> out.print(fileContent) }
+
+    fun writeFileUsingBufferedWriter(fileName: String, fileContent: String) =
+            File(fileName).bufferedWriter().use { out -> out.write(fileContent) }
+
+    fun writeFileDirectly(fileName: String, fileContent: String) =
+            File(fileName).writeText(fileContent)
+
+    fun writeFileDirectlyAsBytes(fileName: String, fileContent: String) =
+            File(fileName).writeBytes(fileContent.toByteArray())
+
+}

core-kotlin/src/main/kotlin/com/baeldung/lambda/Lambda.kt

@@ -0,0 +1,84 @@
+package com.baeldung.lambda
+
+fun inferredType(input: Int): Int {
+    val square = { number: Int -> number * number }
+
+    return square(input)
+}
+
+fun intToBiggerString(argument: Int): String {
+
+    val magnitude100String = { input: Int ->
+        val magnitude = input * 100
+        magnitude.toString()
+    }
+
+    return magnitude100String(argument)
+}
+
+fun manyLambda(nums: Array<Int>): List<String> {
+    val newList = nums.map { intToBiggerString(it) }
+
+    return newList
+}
+
+fun empty() {
+    val noReturn: (Int) -> Unit = { num -> println(num) }
+
+    noReturn(5)
+}
+
+fun invokeLambda(lambda: (Double) -> Boolean): Boolean {
+    return lambda(4.329)
+}
+
+fun extendString(arg: String, num: Int): String {
+    val another: String.(Int) -> String = { this + it }
+
+    return arg.another(num)
+}
+
+fun getCalculationLambda(): (Int) -> Any {
+    val calculateGrade = { grade: Int ->
+        when (grade) {
+            in 0..40 -> "Fail"
+            in 41..70 -> "Pass"
+            in 71..100 -> "Distinction"
+            else -> false
+        }
+    }
+
+    return calculateGrade
+}
+
+fun getCalculationLambdaWithReturn(): (Int) -> String {
+    val calculateGrade: Int.() -> String = lambda@{
+        if (this < 0 || this > 100) {
+            return@lambda "Error"
+        } else if (this < 40) {
+            return@lambda "Fail"
+        } else if (this < 70) {
+            return@lambda "Pass"
+        }
+
+        "Distinction"
+    }
+
+    return calculateGrade
+}
+
+fun getCalculationAnonymousFunction(): (Int) -> String {
+    val calculateGrade = fun(grade: Int): String {
+        if (grade < 0 || grade > 100) {
+            return "Error"
+        } else if (grade < 40) {
+            return "Fail"
+        } else if (grade < 70) {
+            return "Pass"
+        }
+
+        return "Distinction"
+    }
+
+    return calculateGrade
+}

core-kotlin/src/test/java/com/baeldung/lambda/LambdaKotlinTest.java

@@ -0,0 +1,36 @@
+package com.baeldung.lambda;
+
+import kotlin.jvm.functions.Function1;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * Created by Paul Jervis on 24/04/2018.
+ */
+class LambdaKotlinTest {
+
+    @Test
+    void givenJava6_whenUsingAnonnymousClass_thenReturnLambdaResult() {
+        assertTrue(LambdaKt.invokeLambda(new Function1<Double, Boolean>() {
+            @Override
+            public Boolean invoke(Double c) {
+                return c >= 0;
+            }
+        }));
+    }
+
+    @Test
+    void givenJava8_whenUsingLambda_thenReturnLambdaResult() {
+        assertTrue(LambdaKt.invokeLambda(c -> c >= 0));
+    }
+
+    @Test
+    void givenJava8_whenCallingMethodWithStringExtension_thenImplementExtension() {
+        String actual = LambdaKt.extendString("Word", 90);
+        String expected = "Word90";
+
+        assertEquals(expected, actual);
+    }
+}

core-kotlin/src/test/kotlin/com/baeldung/filesystem/FileWriterTest.kt

@@ -0,0 +1,43 @@
+package com.baeldung.filesystem
+
+import org.junit.jupiter.api.Test
+import java.io.File
+import kotlin.test.assertEquals
+
+internal class FileWriterTest {
+
+    private val fileName = "src/test/resources/Kotlin.out"
+
+    private val fileContent = "Kotlin\nConcise, Safe, Interoperable, Tool-friendly"
+
+    private val fileWriter = FileWriter()
+
+    @Test
+    fun whenWrittenWithPrintWriter_thenCorrect() {
+        fileWriter.writeFileUsingPrintWriter(fileName, fileContent)
+
+        assertEquals(fileContent, File(fileName).readText())
+    }
+
+    @Test
+    fun whenWrittenWithBufferedWriter_thenCorrect() {
+        fileWriter.writeFileUsingBufferedWriter(fileName, fileContent)
+
+        assertEquals(fileContent, File(fileName).readText())
+    }
+
+    @Test
+    fun whenWrittenDirectly_thenCorrect() {
+        fileWriter.writeFileDirectly(fileName, fileContent)
+
+        assertEquals(fileContent, File(fileName).readText())
+    }
+
+    @Test
+    fun whenWrittenDirectlyAsBytes_thenCorrect() {
+        fileWriter.writeFileDirectlyAsBytes(fileName, fileContent)
+
+        assertEquals(fileContent, File(fileName).readText())
+    }
+
+}

core-kotlin/src/test/kotlin/com/baeldung/lambda/LambdaTest.kt

@@ -0,0 +1,95 @@
+package com.baeldung.lambda
+
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+
+class LambdaTest {
+    @Test
+    fun whenCallingALambda_thenPerformTheAction() {
+        assertEquals(9, inferredType(3))
+    }
+
+    @Test
+    fun whenCallingAMoreComplicatedLambda_thenPerformTheAction() {
+        assertEquals("500", intToBiggerString(5))
+    }
+
+    @Test
+    fun whenPassingALambdaObject_thenCallTriggerLambda() {
+        val lambda = { arg: Double ->
+            arg == 4.329
+        }
+
+        val result = invokeLambda(lambda)
+
+        assertTrue(result)
+    }
+
+    @Test
+    fun whenPassingALambdaLiteral_thenCallTriggerLambda() {
+        val result = invokeLambda({
+            true
+        })
+
+        assertTrue(result)
+    }
+
+    @Test
+    fun whenPassingALambdaLiteralOutsideBrackets_thenCallTriggerLambda() {
+        val result = invokeLambda { arg -> arg.isNaN() }
+
+        assertFalse(result)
+    }
+
+    @Test
+    fun whenPassingAnAnonymousFunction_thenCallTriggerLambda() {
+        val result = invokeLambda(fun(arg: Double): Boolean {
+            return arg >= 0
+        })
+
+        assertTrue(result)
+    }
+
+    @Test
+    fun whenUsingLambda_thenCalculateGrade() {
+        val gradeCalculation = getCalculationLambda()
+
+        assertEquals(false, gradeCalculation(-40))
+        assertEquals("Pass", gradeCalculation(50))
+    }
+
+    @Test
+    fun whenUsingReturnStatementLambda_thenCalculateGrade() {
+        val gradeCalculation: Int.() -> String = getCalculationLambdaWithReturn()
+
+        assertEquals("Distinction", 80.gradeCalculation())
+        assertEquals("Error", 244_234_324.gradeCalculation())
+    }
+
+    @Test
+    fun whenUsingAnonymousFunction_thenCalculateGrade() {
+        val gradeCalculation = getCalculationAnonymousFunction()
+
+        assertEquals("Error", gradeCalculation(244_234_324))
+        assertEquals("Pass", gradeCalculation(50))
+    }
+
+    @Test
+    fun whenPassingAFunctionReference_thenCallTriggerLambda() {
+        val reference = Double::isFinite
+        val result = invokeLambda(reference)
+
+        assertTrue(result)
+    }
+
+    @Test
+    fun givenArray_whenMappingArray_thenPerformCalculationOnAllElements() {
+        val expected = listOf("100", "200", "300", "400", "500")
+        val actual = manyLambda(arrayOf(1, 2, 3, 4, 5))
+
+        assertEquals(expected, actual)
+    }
+
+}

drools/pom.xml

@@ -5,10 +5,11 @@
     <artifactId>drools</artifactId>
 
     <parent>
-        <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-    </parent>
+		<groupId>com.baeldung</groupId>
+		<artifactId>parent-spring</artifactId>
+		<version>0.0.1-SNAPSHOT</version>
+		<relativePath>../parent-spring</relativePath>
+	</parent>
 
     <dependencies>
         <dependency>
@@ -47,18 +48,13 @@
             <artifactId>poi-ooxml</artifactId>
             <version>${apache-poi-version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-core</artifactId>
-            <version>${spring-core.version}</version>
-        </dependency>
     </dependencies>
 
     <properties>
         <http-component-version>4.4.6</http-component-version>
         <drools-version>7.4.1.Final</drools-version>
         <apache-poi-version>3.13</apache-poi-version>
-        <spring-core.version>4.3.6.RELEASE</spring-core.version>
+        <spring.version>4.3.6.RELEASE</spring.version>
     </properties>
 
 </project>

ethereumj/README.md

@@ -2,3 +2,4 @@
 
 ### Relevant Articles:
 - [Introduction to EthereumJ](http://www.baeldung.com/ethereumj)
+- [Creating and Deploying Smart Contracts with Solidity](http://www.baeldung.com/smart-contracts-ethereum-solidity)

gson/pom.xml

@@ -8,8 +8,9 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
@@ -19,11 +20,6 @@
             <artifactId>joda-time</artifactId>
             <version>${joda-time.version}</version>
         </dependency>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>

guava-modules/guava-18/pom.xml

@@ -8,19 +8,11 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../../parent-java</relativePath>
     </parent>
 
-    <dependencies>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
-    </dependencies>
-
     <properties>
         <guava.version>18.0</guava.version>
     </properties>

guava-modules/guava-19/pom.xml

@@ -8,19 +8,11 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../../parent-java</relativePath>
     </parent>
 
-    <dependencies>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
-    </dependencies>
-
     <properties>
         <guava.version>19.0</guava.version>
     </properties>

guava-modules/guava-21/pom.xml

@@ -7,18 +7,12 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../../parent-java</relativePath>
     </parent>
 
     <dependencies>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
-
         <dependency>
             <groupId>org.jooq</groupId>
             <artifactId>jool</artifactId>

guava/pom.xml

@@ -8,17 +8,13 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <artifactId>parent-java</artifactId>
+    	<version>0.0.1-SNAPSHOT</version>
+    	<relativePath>../parent-java</relativePath>
     </parent>
 
     <dependencies>
         <!-- utils -->
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>${guava.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>

guava/src/test/java/org/baeldung/hamcrest/README.md

@@ -1,2 +1,3 @@
 ### Relevant Articles:
 - [Testing with Hamcrest](http://www.baeldung.com/java-junit-hamcrest-guide)
+- [Hamcrest File Matchers](http://www.baeldung.com/hamcrest-file-matchers)

guest/core-java/pom.xml

@@ -41,11 +41,18 @@
             <version>${org.hamcrest.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <properties>
         <log4j2.version>2.8.2</log4j2.version>
         <org.hamcrest.version>1.3</org.hamcrest.version>
+        <assertj.version>3.6.1</assertj.version>
     </properties>
 
 </project>

guest/core-java/src/main/java/com/stackify/optionalparams/MultiVitamin.java

@@ -1,50 +1,50 @@
-package com.baeldung.optionalparams;
-
-public class MultiVitamin {
-
-    private String name;    // required
-    private int vitaminA;   // in mcg
-    private int vitaminC;   // in mg
-    private int calcium;    // in mg
-    private int iron;       // in mg
-
-    public MultiVitamin(String name) {
-        this.name = name;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public int getVitaminA() {
-        return vitaminA;
-    }
-
-    public void setVitaminA(int vitaminA) {
-        this.vitaminA = vitaminA;
-    }
-
-    public int getVitaminC() {
-        return vitaminC;
-    }
-
-    public void setVitaminC(int vitaminC) {
-        this.vitaminC = vitaminC;
-    }
-
-    public int getCalcium() {
-        return calcium;
-    }
-
-    public void setCalcium(int calcium) {
-        this.calcium = calcium;
-    }
-
-    public int getIron() {
-        return iron;
-    }
-
-    public void setIron(int iron) {
-        this.iron = iron;
-    }
+package com.stackify.optionalparams;
+
+public class MultiVitamin {
+
+    private String name;    // required
+    private int vitaminA;   // in mcg
+    private int vitaminC;   // in mg
+    private int calcium;    // in mg
+    private int iron;       // in mg
+
+    public MultiVitamin(String name) {
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getVitaminA() {
+        return vitaminA;
+    }
+
+    public void setVitaminA(int vitaminA) {
+        this.vitaminA = vitaminA;
+    }
+
+    public int getVitaminC() {
+        return vitaminC;
+    }
+
+    public void setVitaminC(int vitaminC) {
+        this.vitaminC = vitaminC;
+    }
+
+    public int getCalcium() {
+        return calcium;
+    }
+
+    public void setCalcium(int calcium) {
+        this.calcium = calcium;
+    }
+
+    public int getIron() {
+        return iron;
+    }
+
+    public void setIron(int iron) {
+        this.iron = iron;
+    }
 }

guest/core-java/src/main/java/com/stackify/optionalparams/MultiVitaminAllowingNulls.java

@@ -1,4 +1,4 @@
-package com.baeldung.optionalparams;
+package com.stackify.optionalparams;
 
 public class MultiVitaminAllowingNulls {
 

guest/core-java/src/main/java/com/stackify/optionalparams/MultiVitaminOverloading.java

@@ -1,56 +1,56 @@
-package com.baeldung.optionalparams;
-
-public class MultiVitaminOverloading {
-
-    static final int DEFAULT_IRON_AMOUNT = 20;
-
-    private final String name;    // required
-    private final int vitaminA;   // in mcg
-    private final int vitaminC;   // in mg
-    private final int calcium;    // in mg
-    private final int iron;       // in mg
-
-    public MultiVitaminOverloading(String name) {
-        this(name, 0);
-    }
-
-    public MultiVitaminOverloading(String name, int vitaminA) {
-        this(name, vitaminA, 0);
-    }
-
-    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC) {
-        this(name, vitaminA, vitaminC, 0);
-    }
-
-    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC, int calcium) {
-        this(name, vitaminA, vitaminC, calcium, DEFAULT_IRON_AMOUNT);
-    }
-
-    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC, int calcium, int iron) {
-        this.name = name;
-        this.vitaminA = vitaminA;
-        this.vitaminC = vitaminC;
-        this.calcium = calcium;
-        this.iron = iron;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public int getVitaminA() {
-        return vitaminA;
-    }
-
-    public int getVitaminC() {
-        return vitaminC;
-    }
-
-    public int getCalcium() {
-        return calcium;
-    }
-
-    public int getIron() {
-        return iron;
-    }
+package com.stackify.optionalparams;
+
+public class MultiVitaminOverloading {
+
+    static final int DEFAULT_IRON_AMOUNT = 20;
+
+    private final String name;    // required
+    private final int vitaminA;   // in mcg
+    private final int vitaminC;   // in mg
+    private final int calcium;    // in mg
+    private final int iron;       // in mg
+
+    public MultiVitaminOverloading(String name) {
+        this(name, 0);
+    }
+
+    public MultiVitaminOverloading(String name, int vitaminA) {
+        this(name, vitaminA, 0);
+    }
+
+    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC) {
+        this(name, vitaminA, vitaminC, 0);
+    }
+
+    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC, int calcium) {
+        this(name, vitaminA, vitaminC, calcium, DEFAULT_IRON_AMOUNT);
+    }
+
+    public MultiVitaminOverloading(String name, int vitaminA, int vitaminC, int calcium, int iron) {
+        this.name = name;
+        this.vitaminA = vitaminA;
+        this.vitaminC = vitaminC;
+        this.calcium = calcium;
+        this.iron = iron;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getVitaminA() {
+        return vitaminA;
+    }
+
+    public int getVitaminC() {
+        return vitaminC;
+    }
+
+    public int getCalcium() {
+        return calcium;
+    }
+
+    public int getIron() {
+        return iron;
+    }
 }

guest/core-java/src/main/java/com/stackify/optionalparams/MultiVitaminStaticFactoryMethods.java

@@ -1,4 +1,4 @@
-package com.baeldung.optionalparams;
+package com.stackify.optionalparams;
 
 public class MultiVitaminStaticFactoryMethods {
 

guest/core-java/src/main/java/com/stackify/optionalparams/MultiVitaminWithBuilder.java

@@ -1,77 +1,77 @@
-package com.baeldung.optionalparams;
-
-public class MultiVitaminWithBuilder {
-
-    private final String name;    // required
-    private final int vitaminA;   // in mcg
-    private final int vitaminC;   // in mg
-    private final int calcium;    // in mg
-    private final int iron;       // in mg
-
-    private MultiVitaminWithBuilder(MultiVitaminBuilder builder) {
-        this.name = builder.name;
-        this.vitaminA = builder.vitaminA;
-        this.vitaminC = builder.vitaminC;
-        this.calcium = builder.calcium;
-        this.iron = builder.iron;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public int getVitaminA() {
-        return vitaminA;
-    }
-
-    public int getVitaminC() {
-        return vitaminC;
-    }
-
-    public int getCalcium() {
-        return calcium;
-    }
-
-    public int getIron() {
-        return iron;
-    }
-
-    public static class MultiVitaminBuilder {
-
-        private static final int ZERO = 0;
-
-        private final String name; // required
-        private int vitaminA = ZERO;
-        private int vitaminC = ZERO;
-        private int calcium = ZERO;
-        private int iron = ZERO;
-
-        public MultiVitaminBuilder(String name) {
-            this.name = name;
-        }
-
-        public MultiVitaminBuilder withVitaminA(int vitaminA) {
-            this.vitaminA = vitaminA;
-            return this;
-        }
-
-        public MultiVitaminBuilder withVitaminC(int vitaminC) {
-            this.vitaminC = vitaminC;
-            return this;
-        }
-
-        public MultiVitaminBuilder withCalcium(int calcium) {
-            this.calcium = calcium;
-            return this;
-        }
-
-        public MultiVitaminBuilder withIron(int iron) {
-            this.iron = iron;
-            return this;
-        }
-
-        public MultiVitaminWithBuilder build() {
-            return new MultiVitaminWithBuilder(this);
-        }
-    }
-}
+package com.stackify.optionalparams;
+
+public class MultiVitaminWithBuilder {
+
+    private final String name;    // required
+    private final int vitaminA;   // in mcg
+    private final int vitaminC;   // in mg
+    private final int calcium;    // in mg
+    private final int iron;       // in mg
+
+    private MultiVitaminWithBuilder(MultiVitaminBuilder builder) {
+        this.name = builder.name;
+        this.vitaminA = builder.vitaminA;
+        this.vitaminC = builder.vitaminC;
+        this.calcium = builder.calcium;
+        this.iron = builder.iron;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getVitaminA() {
+        return vitaminA;
+    }
+
+    public int getVitaminC() {
+        return vitaminC;
+    }
+
+    public int getCalcium() {
+        return calcium;
+    }
+
+    public int getIron() {
+        return iron;
+    }
+
+    public static class MultiVitaminBuilder {
+
+        private static final int ZERO = 0;
+
+        private final String name; // required
+        private int vitaminA = ZERO;
+        private int vitaminC = ZERO;
+        private int calcium = ZERO;
+        private int iron = ZERO;
+
+        public MultiVitaminBuilder(String name) {
+            this.name = name;
+        }
+
+        public MultiVitaminBuilder withVitaminA(int vitaminA) {
+            this.vitaminA = vitaminA;
+            return this;
+        }
+
+        public MultiVitaminBuilder withVitaminC(int vitaminC) {
+            this.vitaminC = vitaminC;
+            return this;
+        }
+
+        public MultiVitaminBuilder withCalcium(int calcium) {
+            this.calcium = calcium;
+            return this;
+        }
+
+        public MultiVitaminBuilder withIron(int iron) {
+            this.iron = iron;
+            return this;
+        }
+
+        public MultiVitaminWithBuilder build() {
+            return new MultiVitaminWithBuilder(this);
+        }
+    }
+}

guest/core-java/src/test/java/com/stackify/optionalparams/OptionalParamsUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.optionalparams;
+package com.stackify.optionalparams;
 
 import static org.assertj.core.api.Assertions.assertThat;
 

guest/junit5-example/pom.xml

@@ -11,11 +11,6 @@
         <relativePath>../../</relativePath>
     </parent>
     <dependencies>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <version>5.0.0-M4</version>
-        </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-params</artifactId>
@@ -62,4 +57,8 @@
             </plugin>
         </plugins>
     </build>
+    
+    <properties>
+    	
+    </properties>
 </project>