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 install -Pdefault
+script: travis_wait 60 mvn -q install -Pdefault-first,default-second
 
 sudo: required
 

README.md

@@ -26,3 +26,13 @@ To do the full build, do: `mvn install -Pdefault -Dgib.enabled=false`
 Building a single module
 ====================
 To build a specific module run the command: `mvn clean install -Dgib.enabled=false` in the module directory
+
+
+Running a Spring Boot module
+====================
+To run a Spring Boot module run the command: `mvn spring-boot:run -Dgib.enabled=false` in the module directory
+
+
+
+
+

algorithms/README.md

@@ -28,3 +28,6 @@
 - [Calculate the Distance Between Two Points in Java](https://www.baeldung.com/java-distance-between-two-points)
 - [Find the Intersection of Two Lines in Java](https://www.baeldung.com/java-intersection-of-two-lines)
 - [Check If a String Contains All The Letters of The Alphabet](https://www.baeldung.com/java-string-contains-all-letters)
+- [Round Up to the Nearest Hundred](https://www.baeldung.com/java-round-up-nearest-hundred)
+- [Merge Sort in Java](https://www.baeldung.com/java-merge-sort)
+- [Calculate Percentage in Java](https://www.baeldung.com/java-calculate-percentage)

algorithms/pom.xml

@@ -17,6 +17,11 @@
             <artifactId>commons-math3</artifactId>
             <version>${commons-math3.version}</version>
         </dependency>
+        <dependency>
+            <groupId>commons-codec</groupId>
+            <artifactId>commons-codec</artifactId>
+            <version>${commons-codec.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
@@ -85,6 +90,7 @@
         <io.jenetics.version>3.7.0</io.jenetics.version>
         <org.jgrapht.core.version>1.0.1</org.jgrapht.core.version>
         <org.assertj.core.version>3.9.0</org.assertj.core.version>
+        <commons-codec.version>1.11</commons-codec.version>
     </properties>
 
 </project>

algorithms/src/main/java/com/baeldung/algorithms/conversion/HexStringConverter.java

@@ -0,0 +1,110 @@
+package com.baeldung.algorithms.conversion;
+
+import java.math.BigInteger;
+
+import javax.xml.bind.DatatypeConverter;
+
+import org.apache.commons.codec.DecoderException;
+import org.apache.commons.codec.binary.Hex;
+
+import com.google.common.io.BaseEncoding;
+
+public class HexStringConverter {
+
+    /**
+     * Create a byte Array from String of hexadecimal digits using Character conversion 
+     * @param hexString - Hexadecimal digits as String
+     * @return Desired byte Array
+     */
+    public byte[] decodeHexString(String hexString) {
+        if (hexString.length() % 2 == 1) {
+            throw new IllegalArgumentException("Invalid hexadecimal String supplied.");
+        }
+        byte[] bytes = new byte[hexString.length() / 2];
+
+        for (int i = 0; i < hexString.length(); i += 2) {
+            bytes[i / 2] = hexToByte(hexString.substring(i, i + 2));
+        }
+        return bytes;
+    }
+
+    /**
+     * Create a String of hexadecimal digits from a byte Array using Character conversion
+     * @param byteArray - The byte Array
+     * @return Desired String of hexadecimal digits in lower case
+     */
+    public String encodeHexString(byte[] byteArray) {
+        StringBuffer hexStringBuffer = new StringBuffer();
+        for (int i = 0; i < byteArray.length; i++) {
+            hexStringBuffer.append(byteToHex(byteArray[i]));
+        }
+        return hexStringBuffer.toString();
+    }
+
+    public String byteToHex(byte num) {
+        char[] hexDigits = new char[2];
+        hexDigits[0] = Character.forDigit((num >> 4) & 0xF, 16);
+        hexDigits[1] = Character.forDigit((num & 0xF), 16);
+        return new String(hexDigits);
+    }
+
+    public byte hexToByte(String hexString) {
+        int firstDigit = toDigit(hexString.charAt(0));
+        int secondDigit = toDigit(hexString.charAt(1));
+        return (byte) ((firstDigit << 4) + secondDigit);
+    }
+
+    private int toDigit(char hexChar) {
+        int digit = Character.digit(hexChar, 16);
+        if(digit == -1) {
+            throw new IllegalArgumentException("Invalid Hexadecimal Character: "+ hexChar);
+        }
+        return digit;
+    }
+
+    public String encodeUsingBigIntegerToString(byte[] bytes) {
+        BigInteger bigInteger = new BigInteger(1, bytes);
+        return bigInteger.toString(16);
+    }
+
+    public String encodeUsingBigIntegerStringFormat(byte[] bytes) {
+        BigInteger bigInteger = new BigInteger(1, bytes);
+        return String.format("%0" + (bytes.length << 1) + "x", bigInteger);
+    }
+
+    public byte[] decodeUsingBigInteger(String hexString) {
+        byte[] byteArray = new BigInteger(hexString, 16).toByteArray();
+        if (byteArray[0] == 0) {
+            byte[] output = new byte[byteArray.length - 1];
+            System.arraycopy(byteArray, 1, output, 0, output.length);
+            return output;
+        }
+        return byteArray;
+    }
+
+    public String encodeUsingDataTypeConverter(byte[] bytes) {
+        return DatatypeConverter.printHexBinary(bytes);
+    }
+
+    public byte[] decodeUsingDataTypeConverter(String hexString) {
+        return DatatypeConverter.parseHexBinary(hexString);
+    }
+
+    public String encodeUsingApacheCommons(byte[] bytes) throws DecoderException {
+        return Hex.encodeHexString(bytes);
+    }
+
+    public byte[] decodeUsingApacheCommons(String hexString) throws DecoderException {
+        return Hex.decodeHex(hexString);
+    }
+
+    public String encodeUsingGuava(byte[] bytes) {
+        return BaseEncoding.base16()
+            .encode(bytes);
+    }
+
+    public byte[] decodeUsingGuava(String hexString) {
+        return BaseEncoding.base16()
+            .decode(hexString.toUpperCase());
+    }
+}

algorithms/src/main/java/com/baeldung/algorithms/heapsort/Heap.java

@@ -0,0 +1,136 @@
+package com.baeldung.algorithms.heapsort;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class Heap<E extends Comparable<E>> {
+
+    private List<E> elements = new ArrayList<>();
+
+    public static <E extends Comparable<E>> List<E> sort(Iterable<E> elements) {
+        Heap<E> heap = of(elements);
+
+        List<E> result = new ArrayList<>();
+
+        while (!heap.isEmpty()) {
+            result.add(heap.pop());
+        }
+
+        return result;
+    }
+
+    public static <E extends Comparable<E>> Heap<E> of(E... elements) {
+        return of(Arrays.asList(elements));
+    }
+
+    public static <E extends Comparable<E>> Heap<E> of(Iterable<E> elements) {
+        Heap<E> result = new Heap<>();
+        for (E element : elements) {
+            result.add(element);
+        }
+        return result;
+    }
+
+    public void add(E e) {
+        elements.add(e);
+        int elementIndex = elements.size() - 1;
+        while (!isRoot(elementIndex) && !isCorrectChild(elementIndex)) {
+            int parentIndex = parentIndex(elementIndex);
+            swap(elementIndex, parentIndex);
+            elementIndex = parentIndex;
+        }
+    }
+
+    public E pop() {
+        if (isEmpty()) {
+            throw new IllegalStateException("You cannot pop from an empty heap");
+        }
+
+        E result = elementAt(0);
+
+        int lasElementIndex = elements.size() - 1;
+        swap(0, lasElementIndex);
+        elements.remove(lasElementIndex);
+
+        int elementIndex = 0;
+        while (!isLeaf(elementIndex) && !isCorrectParent(elementIndex)) {
+            int smallerChildIndex = smallerChildIndex(elementIndex);
+            swap(elementIndex, smallerChildIndex);
+            elementIndex = smallerChildIndex;
+        }
+
+        return result;
+    }
+
+    public boolean isEmpty() {
+        return elements.isEmpty();
+    }
+    
+    private boolean isRoot(int index) {
+        return index == 0;
+    }
+
+    private int smallerChildIndex(int index) {
+        int leftChildIndex = leftChildIndex(index);
+        int rightChildIndex = rightChildIndex(index);
+        
+        if (!isValidIndex(rightChildIndex)) {
+            return leftChildIndex;
+        }
+
+        if (elementAt(leftChildIndex).compareTo(elementAt(rightChildIndex)) < 0) {
+            return leftChildIndex;
+        }
+
+        return rightChildIndex;
+    }
+
+    private boolean isLeaf(int index) {
+        return !isValidIndex(leftChildIndex(index));
+    }
+
+    private boolean isCorrectParent(int index) {
+        return isCorrect(index, leftChildIndex(index)) && isCorrect(index, rightChildIndex(index));
+    }
+
+    private boolean isCorrectChild(int index) {
+        return isCorrect(parentIndex(index), index);
+    }
+
+    private boolean isCorrect(int parentIndex, int childIndex) {
+        if (!isValidIndex(parentIndex) || !isValidIndex(childIndex)) {
+            return true;
+        }
+
+        return elementAt(parentIndex).compareTo(elementAt(childIndex)) < 0;
+    }
+
+    private boolean isValidIndex(int index) {
+        return index < elements.size();
+    }
+
+    private void swap(int index1, int index2) {
+        E element1 = elementAt(index1);
+        E element2 = elementAt(index2);
+        elements.set(index1, element2);
+        elements.set(index2, element1);
+    }
+
+    private E elementAt(int index) {
+        return elements.get(index);
+    }
+
+    private int parentIndex(int index) {
+        return (index - 1) / 2;
+    }
+
+    private int leftChildIndex(int index) {
+        return 2 * index + 1;
+    }
+
+    private int rightChildIndex(int index) {
+        return 2 * index + 2;
+    }
+
+}

algorithms/src/test/java/com/baeldung/algorithms/conversion/ByteArrayConverterUnitTest.java

@@ -0,0 +1,127 @@
+package com.baeldung.algorithms.conversion;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+
+import org.apache.commons.codec.DecoderException;
+import org.hamcrest.text.IsEqualIgnoringCase;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.algorithms.conversion.HexStringConverter;
+
+public class ByteArrayConverterUnitTest {
+
+    private HexStringConverter hexStringConverter;
+
+    @Before
+    public void setup() {
+        hexStringConverter = new HexStringConverter();
+    }
+
+    @Test
+    public void shouldEncodeByteArrayToHexStringUsingBigIntegerToString() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        if(hexString.charAt(0) == '0') {
+            hexString = hexString.substring(1);
+        }
+        String output = hexStringConverter.encodeUsingBigIntegerToString(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldEncodeByteArrayToHexStringUsingBigIntegerStringFormat() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        String output = hexStringConverter.encodeUsingBigIntegerStringFormat(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldDecodeHexStringToByteArrayUsingBigInteger() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        byte[] output = hexStringConverter.decodeUsingBigInteger(hexString);
+        assertArrayEquals(bytes, output);
+    }
+    
+    @Test
+    public void shouldEncodeByteArrayToHexStringUsingCharacterConversion() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        String output = hexStringConverter.encodeHexString(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldDecodeHexStringToByteArrayUsingCharacterConversion() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        byte[] output = hexStringConverter.decodeHexString(hexString);
+        assertArrayEquals(bytes, output);
+    }
+    
+    @Test(expected=IllegalArgumentException.class)
+    public void shouldDecodeHexToByteWithInvalidHexCharacter() {
+        hexStringConverter.hexToByte("fg");
+    }
+
+    @Test
+    public void shouldEncodeByteArrayToHexStringDataTypeConverter() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        String output = hexStringConverter.encodeUsingDataTypeConverter(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldDecodeHexStringToByteArrayUsingDataTypeConverter() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        byte[] output = hexStringConverter.decodeUsingDataTypeConverter(hexString);
+        assertArrayEquals(bytes, output);
+    }
+
+    @Test
+    public void shouldEncodeByteArrayToHexStringUsingGuava() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        String output = hexStringConverter.encodeUsingGuava(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldDecodeHexStringToByteArrayUsingGuava() {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        byte[] output = hexStringConverter.decodeUsingGuava(hexString);
+        assertArrayEquals(bytes, output);
+    }
+
+    @Test
+    public void shouldEncodeByteArrayToHexStringUsingApacheCommons() throws DecoderException {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        String output = hexStringConverter.encodeUsingApacheCommons(bytes);
+        assertThat(output, IsEqualIgnoringCase.equalToIgnoringCase(hexString));
+    }
+
+    @Test
+    public void shouldDecodeHexStringToByteArrayUsingApacheCommons() throws DecoderException {
+        byte[] bytes = getSampleBytes();
+        String hexString = getSampleHexString();
+        byte[] output = hexStringConverter.decodeUsingApacheCommons(hexString);
+        assertArrayEquals(bytes, output);
+    }
+
+    private String getSampleHexString() {
+        return "0af50c0e2d10";
+    }
+
+    private byte[] getSampleBytes() {
+        return new byte[] { 10, -11, 12, 14, 45, 16 };
+    }
+
+}

algorithms/src/test/java/com/baeldung/algorithms/heapsort/HeapUnitTest.java

@@ -0,0 +1,36 @@
+package com.baeldung.algorithms.heapsort;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+
+public class HeapUnitTest {
+
+    @Test
+    public void givenNotEmptyHeap_whenPopCalled_thenItShouldReturnSmallestElement() {
+        // given
+        Heap<Integer> heap = Heap.of(3, 5, 1, 4, 2);
+
+        // when
+        int head = heap.pop();
+
+        // then
+        assertThat(head).isEqualTo(1);
+    }
+    
+    @Test
+    public void givenNotEmptyIterable_whenSortCalled_thenItShouldReturnElementsInSortedList() {
+        // given
+        List<Integer> elements = Arrays.asList(3, 5, 1, 4, 2);
+        
+        // when
+        List<Integer> sortedElements = Heap.sort(elements);
+        
+        // then
+        assertThat(sortedElements).isEqualTo(Arrays.asList(1, 2, 3, 4, 5));
+    }
+
+}

apache-pulsar/.gitignore

@@ -0,0 +1,8 @@
+.classpath
+.project
+.settings
+target
+.idea
+*.iml
+.gradle/
+build/

apache-pulsar/pom.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>com.baeldung.pulsar</groupId>
+  <artifactId>pulsar-java</artifactId>
+  <version>0.0.1</version>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.apache.pulsar</groupId>
+      <artifactId>pulsar-client</artifactId>
+      <version>2.1.1-incubating</version>
+      <scope>compile</scope>
+    </dependency>
+  </dependencies>
+  <properties>
+    <maven.compiler.target>1.8</maven.compiler.target>
+    <maven.compiler.source>1.8</maven.compiler.source>
+  </properties>
+</project>

apache-pulsar/src/main/java/com/baeldung/ConsumerTest.java

@@ -0,0 +1,48 @@
+package com.baeldung;
+
+import java.io.IOException;
+
+import org.apache.pulsar.client.api.Consumer;
+import org.apache.pulsar.client.api.Message;
+import org.apache.pulsar.client.api.PulsarClient;
+import org.apache.pulsar.client.api.SubscriptionType;
+
+public class ConsumerTest {
+
+    private static final String SERVICE_URL = "pulsar://localhost:6650";
+    private static final String TOPIC_NAME = "test-topic";
+    private static final String SUBSCRIPTION_NAME = "test-subscription";
+
+    public static void main(String[] args) throws IOException {
+        // Create a Pulsar client instance. A single instance can be shared across many
+        // producers and consumer within the same application
+        PulsarClient client = PulsarClient.builder()
+                .serviceUrl(SERVICE_URL)
+                .build();
+
+        //Configure consumer specific settings.
+        Consumer<byte[]> consumer = client.newConsumer()
+                .topic(TOPIC_NAME)
+                // Allow multiple consumers to attach to the same subscription
+                // and get messages dispatched as a queue
+                .subscriptionType(SubscriptionType.Shared)
+                .subscriptionName(SUBSCRIPTION_NAME)
+                .subscribe();
+
+
+        // Once the consumer is created, it can be used for the entire application lifecycle
+        System.out.println("Created consumer for the topic "+ TOPIC_NAME);
+
+        do {
+            // Wait until a message is available
+            Message<byte[]> msg = consumer.receive();
+
+            // Extract the message as a printable string and then log
+            String content = new String(msg.getData());
+            System.out.println("Received message '"+content+"' with ID "+msg.getMessageId());
+
+            // Acknowledge processing of the message so that it can be deleted
+            consumer.acknowledge(msg);
+        } while (true);
+    }
+}

apache-pulsar/src/main/java/com/baeldung/ProducerTest.java

@@ -0,0 +1,58 @@
+package com.baeldung;
+
+import org.apache.pulsar.client.api.CompressionType;
+import org.apache.pulsar.client.api.Message;
+import org.apache.pulsar.client.api.MessageBuilder;
+import org.apache.pulsar.client.api.MessageId;
+import org.apache.pulsar.client.api.Producer;
+import org.apache.pulsar.client.api.PulsarClient;
+import org.apache.pulsar.client.api.PulsarClientException;
+
+import java.io.IOException;
+import java.util.stream.IntStream;
+
+public class ProducerTest {
+
+    private static final String SERVICE_URL = "pulsar://localhost:6650";
+    private static final String TOPIC_NAME = "test-topic";
+
+    public static void main(String[] args) throws IOException {
+        // Create a Pulsar client instance. A single instance can be shared across many
+        // producers and consumer within the same application
+        PulsarClient client = PulsarClient.builder()
+                .serviceUrl(SERVICE_URL)
+                .build();
+
+        // Configure producer specific settings
+        Producer<byte[]> producer = client.newProducer()
+                // Set the topic
+                .topic(TOPIC_NAME)
+                // Enable compression
+                .compressionType(CompressionType.LZ4)
+                .create();
+
+        // Once the producer is created, it can be used for the entire application life-cycle
+        System.out.println("Created producer for the topic "+TOPIC_NAME);
+
+        // Send 5 test messages
+        IntStream.range(1, 5).forEach(i -> {
+            String content = String.format("hi-pulsar-%d", i);
+
+            // Build a message object
+            Message<byte[]> msg = MessageBuilder.create()
+                    .setContent(content.getBytes())
+                    .build();
+
+            // Send each message and log message content and ID when successfully received
+            try {
+                MessageId msgId = producer.send(msg);
+
+                System.out.println("Published message '"+content+"' with the ID "+msgId);
+            } catch (PulsarClientException e) {
+                System.out.println(e.getMessage());
+            }
+        });
+
+        client.close();
+    }
+}

apache-pulsar/src/main/java/com/baeldung/subscriptions/ExclusiveSubscriptionTest.java

@@ -0,0 +1,59 @@
+package com.baeldung.subscriptions;
+
+import org.apache.pulsar.client.api.ConsumerBuilder;
+import org.apache.pulsar.client.api.Message;
+import org.apache.pulsar.client.api.MessageBuilder;
+import org.apache.pulsar.client.api.Producer;
+import org.apache.pulsar.client.api.PulsarClient;
+import org.apache.pulsar.client.api.PulsarClientException;
+import org.apache.pulsar.client.api.SubscriptionType;
+
+import java.util.stream.IntStream;
+
+public class ExclusiveSubscriptionTest {
+    private static final String SERVICE_URL = "pulsar://localhost:6650";
+    private static final String TOPIC_NAME = "test-topic";
+    private static final String SUBSCRIPTION_NAME = "test-subscription";
+    private static final SubscriptionType SUBSCRIPTION_TYPE = SubscriptionType.Exclusive;
+
+    public static void main(String[] args) throws PulsarClientException {
+        PulsarClient client = PulsarClient.builder()
+                .serviceUrl(SERVICE_URL)
+                .build();
+
+        Producer<byte[]> producer = client.newProducer()
+                .topic(TOPIC_NAME)
+                .create();
+
+        ConsumerBuilder<byte[]> consumer1 = client.newConsumer()
+                .topic(TOPIC_NAME)
+                .subscriptionName(SUBSCRIPTION_NAME)
+                .subscriptionType(SUBSCRIPTION_TYPE);
+
+        ConsumerBuilder<byte[]> consumer2 = client.newConsumer()
+                .topic(TOPIC_NAME)
+                .subscriptionName(SUBSCRIPTION_NAME)
+                .subscriptionType(SUBSCRIPTION_TYPE);
+
+        IntStream.range(0, 999).forEach(i -> {
+            Message<byte[]> msg = MessageBuilder.create()
+                    .setContent(String.format("message-%d", i).getBytes())
+                    .build();
+            try {
+                producer.send(msg);
+            } catch (PulsarClientException e) {
+                System.out.println(e.getMessage());
+            }
+        });
+
+        // Consumer 1 can subscribe to the topic
+        consumer1.subscribe();
+
+        // Consumer 2 cannot due to the exclusive subscription held by consumer 1
+        consumer2.subscribeAsync()
+                .handle((consumer, exception) -> {
+                    System.out.println(exception.getMessage());
+                    return null;
+                });
+    }
+}

apache-pulsar/src/main/java/com/baeldung/subscriptions/FailoverSubscriptionTest.java

@@ -0,0 +1,76 @@
+package com.baeldung.subscriptions;
+
+import org.apache.pulsar.client.api.Consumer;
+import org.apache.pulsar.client.api.ConsumerBuilder;
+import org.apache.pulsar.client.api.Message;
+import org.apache.pulsar.client.api.MessageBuilder;
+import org.apache.pulsar.client.api.Producer;
+import org.apache.pulsar.client.api.PulsarClient;
+import org.apache.pulsar.client.api.PulsarClientException;
+import org.apache.pulsar.client.api.SubscriptionType;
+
+import java.util.stream.IntStream;
+
+public class FailoverSubscriptionTest {
+    private static final String SERVICE_URL = "pulsar://localhost:6650";
+    private static final String TOPIC_NAME = "failover-subscription-test-topic";
+    private static final String SUBSCRIPTION_NAME = "test-subscription";
+    private static final SubscriptionType SUBSCRIPTION_TYPE = SubscriptionType.Failover;
+    private static final int NUM_MSGS = 10;
+
+    public static void main(String[] args) throws PulsarClientException {
+        PulsarClient client = PulsarClient.builder()
+                .serviceUrl(SERVICE_URL)
+                .build();
+
+        Producer<byte[]> producer = client.newProducer()
+                .topic(TOPIC_NAME)
+                .create();
+
+        ConsumerBuilder<byte[]> consumerBuilder = client.newConsumer()
+                .topic(TOPIC_NAME)
+                .subscriptionName(SUBSCRIPTION_NAME)
+                .subscriptionType(SUBSCRIPTION_TYPE);
+
+        Consumer<byte[]> mainConsumer = consumerBuilder
+                .consumerName("consumer-a")
+                .messageListener((consumer, msg) -> {
+                    System.out.println("Message received by main consumer");
+
+                    try {
+                        consumer.acknowledge(msg);
+                    } catch (PulsarClientException e) {
+                        System.out.println(e.getMessage());
+                    }
+                })
+                .subscribe();
+
+        Consumer<byte[]> failoverConsumer = consumerBuilder
+                .consumerName("consumer-b")
+                .messageListener((consumer, msg) -> {
+                    System.out.println("Message received by failover consumer");
+
+                    try {
+                        consumer.acknowledge(msg);
+                    } catch (PulsarClientException e) {
+                        System.out.println(e.getMessage());
+                    }
+                })
+                .subscribe();
+
+        IntStream.range(0, NUM_MSGS).forEach(i -> {
+            Message<byte[]> msg = MessageBuilder.create()
+                    .setContent(String.format("message-%d", i).getBytes())
+                    .build();
+            try {
+                producer.send(msg);
+
+                Thread.sleep(100);
+
+                if (i > 5) mainConsumer.close();
+            } catch (InterruptedException | PulsarClientException e) {
+                System.out.println(e.getMessage());
+            }
+        });
+    }
+}

aws/README.md

@@ -9,4 +9,4 @@
 - [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)
-
+- [Guide to AWS Aurora RDS with Java](https://www.baeldung.com/aws-aurora-rds-java)

core-java-8/README.md

@@ -32,3 +32,4 @@
 - [Set the Time Zone of a Date in Java](https://www.baeldung.com/java-set-date-time-zone)
 - [An Overview of Regular Expressions Performance in Java](https://www.baeldung.com/java-regex-performance)
 - [Java Primitives versus Objects](https://www.baeldung.com/java-primitives-vs-objects)
+- [How to Use if/else Logic in Java 8 Streams](https://www.baeldung.com/java-8-streams-if-else-logic)

core-java-9/README.md

@@ -26,3 +26,4 @@
 - [Iterate Through a Range of Dates in Java](https://www.baeldung.com/java-iterate-date-range)
 - [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
 - [Java 9 Platform Logging API](https://www.baeldung.com/java-9-logging-api)
+- [Guide to java.lang.Process API](https://www.baeldung.com/java-process-api)

core-java-collections/README.md

@@ -4,37 +4,23 @@
 
 ### 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)
-- [How to Store Duplicate Keys in a Map in Java?](http://www.baeldung.com/java-map-duplicate-keys)
 - [Getting the Size of an Iterable in Java](http://www.baeldung.com/java-iterable-size)
 - [Iterating Backward Through a List](http://www.baeldung.com/java-list-iterate-backwards)
 - [How to Filter a Collection in Java](http://www.baeldung.com/java-collection-filtering)
 - [Add Multiple Items to an Java ArrayList](http://www.baeldung.com/java-add-items-array-list)
 - [Remove the First Element from a List](http://www.baeldung.com/java-remove-first-element-from-list)
-- [How to Convert List to Map in Java](http://www.baeldung.com/java-list-to-map)
 - [Initializing HashSet at the Time of Construction](http://www.baeldung.com/java-initialize-hashset)
 - [Removing the First Element of an Array](https://www.baeldung.com/java-array-remove-first-element)
 - [Fail-Safe Iterator vs Fail-Fast Iterator](http://www.baeldung.com/java-fail-safe-vs-fail-fast-iterator)
@@ -47,8 +33,8 @@
 - [Remove All Occurrences of a Specific Value from a List](https://www.baeldung.com/java-remove-value-from-list)
 - [Thread Safe LIFO Data Structure Implementations](https://www.baeldung.com/java-lifo-thread-safe)
 - [Collections.emptyList() vs. New List Instance](https://www.baeldung.com/java-collections-emptylist-new-list)
-- [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
 - [Differences Between Collection.clear() and Collection.removeAll()](https://www.baeldung.com/java-collection-clear-vs-removeall)
 - [Performance of contains() in a HashSet vs ArrayList](https://www.baeldung.com/java-hashset-arraylist-contains-performance)
-- [Get the Key for a Value from a Java Map](https://www.baeldung.com/java-map-key-from-value)
 - [Time Complexity of Java Collections](https://www.baeldung.com/java-collections-complexity)
+- [Operating on and Removing an Item from Stream](https://www.baeldung.com/java-use-remove-item-stream)
+- [An Introduction to Synchronized Java Collections](https://www.baeldung.com/java-synchronized-collections)

core-java-collections/pom.xml

@@ -14,22 +14,11 @@
     </parent>
 
     <dependencies>
-        <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>
@@ -67,12 +56,6 @@
             <artifactId>commons-exec</artifactId>
             <version>1.3</version>
         </dependency>
-        
-        <dependency>
-            <groupId>one.util</groupId>
-            <artifactId>streamex</artifactId>
-            <version>0.6.5</version>
-        </dependency>
     </dependencies>
 
     <properties>

core-java-collections/src/main/java/com/baeldung/enumset/EnumSets.java

@@ -0,0 +1,45 @@
+package com.baeldung.enumset;
+
+import java.util.ArrayList;
+import java.util.EnumSet;
+import java.util.List;
+
+public class EnumSets {
+
+    public enum Color {
+        RED, YELLOW, GREEN, BLUE, BLACK, WHITE
+    }
+
+    public static void main(String[] args) {
+        EnumSet<Color> allColors = EnumSet.allOf(Color.class);
+        System.out.println(allColors);
+
+        EnumSet<Color> noColors = EnumSet.noneOf(Color.class);
+        System.out.println(noColors);
+
+        EnumSet<Color> blackAndWhite = EnumSet.of(Color.BLACK, Color.WHITE);
+        System.out.println(blackAndWhite);
+
+        EnumSet<Color> noBlackOrWhite = EnumSet.complementOf(blackAndWhite);
+        System.out.println(noBlackOrWhite);
+
+        EnumSet<Color> range = EnumSet.range(Color.YELLOW, Color.BLUE);
+        System.out.println(range);
+
+        EnumSet<Color> blackAndWhiteCopy = EnumSet.copyOf(EnumSet.of(Color.BLACK, Color.WHITE));
+        System.out.println(blackAndWhiteCopy);
+
+        List<Color> colorsList = new ArrayList<>();
+        colorsList.add(Color.RED);
+        EnumSet<Color> listCopy = EnumSet.copyOf(colorsList);
+        System.out.println(listCopy);
+
+        EnumSet<Color> set = EnumSet.noneOf(Color.class);
+        set.add(Color.RED);
+        set.add(Color.YELLOW);
+        set.contains(Color.RED);
+        set.forEach(System.out::println);
+        set.remove(Color.RED);
+    }
+
+}

core-java-collections/src/main/java/com/baeldung/removal/CollectionRemoveIf.java

@@ -0,0 +1,19 @@
+package com.baeldung.removal;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+public class CollectionRemoveIf {
+
+    public static void main(String args[]) {
+        Collection<String> names = new ArrayList<>();
+        names.add("John");
+        names.add("Ana");
+        names.add("Mary");
+        names.add("Anthony");
+        names.add("Mark");
+
+        names.removeIf(e -> e.startsWith("A"));
+        System.out.println(String.join(",", names));
+    }
+}

core-java-collections/src/main/java/com/baeldung/removal/Iterators.java

@@ -0,0 +1,28 @@
+package com.baeldung.removal;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Iterator;
+
+public class Iterators {
+
+    public static void main(String args[]) {
+        Collection<String> names = new ArrayList<>();
+        names.add("John");
+        names.add("Ana");
+        names.add("Mary");
+        names.add("Anthony");
+        names.add("Mark");
+
+        Iterator<String> i = names.iterator();
+
+        while (i.hasNext()) {
+            String e = i.next();
+            if (e.startsWith("A")) {
+                i.remove();
+            }
+        }
+
+        System.out.println(String.join(",", names));
+    }
+}

core-java-collections/src/main/java/com/baeldung/removal/StreamFilterAndCollector.java

@@ -0,0 +1,23 @@
+package com.baeldung.removal;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.stream.Collectors;
+
+public class StreamFilterAndCollector {
+
+    public static void main(String args[]) {
+        Collection<String> names = new ArrayList<>();
+        names.add("John");
+        names.add("Ana");
+        names.add("Mary");
+        names.add("Anthony");
+        names.add("Mark");
+
+        Collection<String> filteredCollection = names
+                .stream()
+                .filter(e -> !e.startsWith("A"))
+                .collect(Collectors.toList());
+        System.out.println(String.join(",", filteredCollection));
+    }
+}

core-java-collections/src/main/java/com/baeldung/removal/StreamPartitioningBy.java

@@ -0,0 +1,28 @@
+package com.baeldung.removal;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class StreamPartitioningBy {
+
+    public static void main(String args[]) {
+        Collection<String> names = new ArrayList<>();
+        names.add("John");
+        names.add("Ana");
+        names.add("Mary");
+        names.add("Anthony");
+        names.add("Mark");
+
+        Map<Boolean, List<String>> classifiedElements = names
+                .stream()
+                .collect(Collectors.partitioningBy((String e) -> !e.startsWith("A")));
+
+        String matching = String.join(",", classifiedElements.get(Boolean.TRUE));
+        String nonMatching = String.join(",", classifiedElements.get(Boolean.FALSE));
+        System.out.println("Matching elements: " + matching);
+        System.out.println("Non matching elements: " + nonMatching);
+    }
+}

core-java-collections/src/test/java/com/baeldung/findItems/FindItemsBasedOnOtherStreamUnitTest.java

@@ -0,0 +1,89 @@
+package com.baeldung.findItems;
+
+import static org.junit.Assert.assertEquals;
+
+import java.text.ParseException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.junit.Test;
+
+public class FindItemsBasedOnOtherStreamUnitTest {
+
+    private List<Employee> employeeList = new ArrayList<Employee>();
+
+    private List<Department> departmentList = new ArrayList<Department>();
+
+    @Test
+    public void givenDepartmentList_thenEmployeeListIsFilteredCorrectly() {
+        Integer expectedId = 1002;
+
+        populate(employeeList, departmentList);
+
+        List<Employee> filteredList = employeeList.stream()
+            .filter(empl -> departmentList.stream()
+                .anyMatch(dept -> dept.getDepartment()
+                    .equals("sales") && empl.getEmployeeId()
+                    .equals(dept.getEmployeeId())))
+            .collect(Collectors.toList());
+
+        assertEquals(expectedId, filteredList.get(0)
+            .getEmployeeId());
+    }
+
+    private void populate(List<Employee> EmplList, List<Department> deptList) {
+        Employee employee1 = new Employee(1001, "empl1");
+        Employee employee2 = new Employee(1002, "empl2");
+        Employee employee3 = new Employee(1003, "empl3");
+
+        Collections.addAll(EmplList, employee1, employee2, employee3);
+
+        Department department1 = new Department(1002, "sales");
+        Department department2 = new Department(1003, "marketing");
+        Department department3 = new Department(1004, "sales");
+
+        Collections.addAll(deptList, department1, department2, department3);
+    }
+}
+
+class Employee {
+    private Integer employeeId;
+    private String employeeName;
+
+    Employee(Integer employeeId, String employeeName) {
+        super();
+        this.employeeId = employeeId;
+        this.employeeName = employeeName;
+    }
+
+    Integer getEmployeeId() {
+        return employeeId;
+    }
+
+    public String getEmployeeName() {
+        return employeeName;
+    }
+
+}
+
+class Department {
+    private Integer employeeId;
+    private String department;
+
+    Department(Integer employeeId, String department) {
+        super();
+        this.employeeId = employeeId;
+        this.department = department;
+    }
+
+    Integer getEmployeeId() {
+        return employeeId;
+    }
+
+    String getDepartment() {
+        return department;
+    }
+
+}

core-java-collections/src/test/java/com/baeldung/removal/RemovalUnitTest.java

@@ -0,0 +1,77 @@
+package com.baeldung.removal;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+public class RemovalUnitTest {
+
+    Collection<String> names;
+    Collection<String> expected;
+    Collection<String> removed;
+
+    @Before
+    public void setupTestData() {
+        names = new ArrayList<>();
+        expected = new ArrayList<>();
+        removed = new ArrayList<>();
+
+        names.add("John");
+        names.add("Ana");
+        names.add("Mary");
+        names.add("Anthony");
+        names.add("Mark");
+
+        expected.add("John");
+        expected.add("Mary");
+        expected.add("Mark");
+
+        removed.add("Ana");
+        removed.add("Anthony");
+    }
+
+    @Test
+    public void givenCollectionOfNames_whenUsingIteratorToRemoveAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
+        Iterator<String> i = names.iterator();
+
+        while (i.hasNext()) {
+            String e = i.next();
+            if (e.startsWith("A")) {
+                i.remove();
+            }
+        }
+
+        assertThat(names, is(expected));
+    }
+
+    @Test
+    public void givenCollectionOfNames_whenUsingRemoveIfToRemoveAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
+        names.removeIf(e -> e.startsWith("A"));
+        assertThat(names, is(expected));
+    }
+
+    @Test
+    public void givenCollectionOfNames_whenUsingStreamToFilterAllNamesStartingWithLetterA_finalListShouldContainNoNamesStartingWithLetterA() {
+        Collection<String> filteredCollection = names
+                .stream()
+                .filter(e -> !e.startsWith("A"))
+                .collect(Collectors.toList());
+        assertThat(filteredCollection, is(expected));
+    }
+
+    @Test
+    public void givenCollectionOfNames_whenUsingStreamAndPartitioningByToFindNamesThatStartWithLetterA_shouldFind3MatchingAnd2NonMatching() {
+        Map<Boolean, List<String>> classifiedElements = names
+                .stream()
+                .collect(Collectors.partitioningBy((String e) -> !e.startsWith("A")));
+
+        assertThat(classifiedElements.get(Boolean.TRUE), is(expected));
+        assertThat(classifiedElements.get(Boolean.FALSE), is(removed));
+    }
+
+}

core-java-concurrency/README.md

@@ -29,3 +29,4 @@
 - [A Custom Spring SecurityConfigurer](http://www.baeldung.com/spring-security-custom-configurer)
 - [Life Cycle of a Thread in Java](http://www.baeldung.com/java-thread-lifecycle)
 - [Runnable vs. Callable in Java](http://www.baeldung.com/java-runnable-callable)
+- [Brief Introduction to Java Thread.yield()](https://www.baeldung.com/java-thread-yield)

core-java-concurrency/src/test/java/com/baeldung/completablefuture/CompletableFutureLongRunningUnitTest.java

@@ -184,5 +184,25 @@ public class CompletableFutureLongRunningUnitTest {
 
         assertEquals("Hello World", future.get());
     }
+    
+    @Test
+    public void whenPassingTransformation_thenFunctionExecutionWithThenApply() throws InterruptedException, ExecutionException {
+        CompletableFuture<Integer> finalResult = compute().thenApply(s -> s + 1);
+        assertTrue(finalResult.get() == 11);
+    }
+    
+    @Test
+    public void whenPassingPreviousStage_thenFunctionExecutionWithThenCompose() throws InterruptedException, ExecutionException {
+        CompletableFuture<Integer> finalResult = compute().thenCompose(this::computeAnother);
+        assertTrue(finalResult.get() == 20);
+    }
+    
+    public CompletableFuture<Integer> compute(){
+        return CompletableFuture.supplyAsync(() -> 10);
+    }
+    
+    public CompletableFuture<Integer> computeAnother(Integer i){
+        return CompletableFuture.supplyAsync(() -> 10 + i);
+    }
 
 }

core-java-io/src/main/resources/zipTest/test1.txt

@@ -0,0 +1 @@
+Test1

core-java-io/src/main/resources/zipTest/test2.txt

@@ -0,0 +1 @@
+Test2

core-java/README.md

@@ -29,7 +29,6 @@
 - [AWS Lambda With Java](http://www.baeldung.com/java-aws-lambda)
 - [Introduction to Nashorn](http://www.baeldung.com/java-nashorn)
 - [Chained Exceptions in Java](http://www.baeldung.com/java-chained-exceptions)
-- [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)
 - [JVM Log Forging](http://www.baeldung.com/jvm-log-forging)
@@ -150,3 +149,11 @@
 - [Throw Exception in Optional in Java 8](https://www.baeldung.com/java-optional-throw-exception)
 - [Add a Character to a String at a Given Position](https://www.baeldung.com/java-add-character-to-string)
 - [Synthetic Constructs in Java](https://www.baeldung.com/java-synthetic)
+- [Calculating the nth Root in Java](https://www.baeldung.com/java-nth-root)
+- [Convert Double to String, Removing Decimal Places](https://www.baeldung.com/java-double-to-string)
+- [Different Ways to Capture Java Heap Dumps](https://www.baeldung.com/java-heap-dump-capture)
+- [How to Separate Double into Integer and Decimal Parts](https://www.baeldung.com/java-separate-double-into-integer-decimal-parts)
+- [ZoneOffset in Java](https://www.baeldung.com/java-zone-offset)
+- [Hashing a Password in Java](https://www.baeldung.com/java-password-hashing)
+- [Java Switch Statement](https://www.baeldung.com/java-switch)
+- [The Modulo Operator in Java](https://www.baeldung.com/modulo-java)

core-java/src/main/java/com/baeldung/array/ArrayReferenceGuide.java

@@ -0,0 +1,159 @@
+package com.baeldung.array;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+
+public class ArrayReferenceGuide {
+
+    public static void main(String[] args) {
+        declaration();
+
+        initialization();
+
+        access();
+
+        iterating();
+
+        varargs();
+
+        transformIntoList();
+
+        transformIntoStream();
+
+        sort();
+
+        search();
+
+        merge();
+    }
+
+    private static void declaration() {
+        int[] anArray;
+        int anotherArray[];
+    }
+
+    private static void initialization() {
+        int[] anArray = new int[10];
+        anArray[0] = 10;
+        anArray[5] = 4;
+
+        int[] anotherArray = new int[] {1, 2, 3, 4, 5};
+    }
+
+    private static void access() {
+        int[] anArray = new int[10];
+        anArray[0] = 10;
+        anArray[5] = 4;
+
+        System.out.println(anArray[0]);
+    }
+
+    private static void iterating() {
+        int[] anArray = new int[] {1, 2, 3, 4, 5};
+        for (int i = 0; i < anArray.length; i++) {
+            System.out.println(anArray[i]);
+        }
+
+        for (int element : anArray) {
+            System.out.println(element);
+        }
+    }
+
+    private static void varargs() {
+        String[] groceries = new String[] {"Milk", "Tomato", "Chips"};
+        varargMethod(groceries);
+        varargMethod("Milk", "Tomato", "Chips");
+    }
+
+    private static void varargMethod(String... varargs) {
+        for (String element : varargs) {
+            System.out.println(element);
+        }
+    }
+
+    private static void transformIntoList() {
+        Integer[] anArray = new Integer[] {1, 2, 3, 4, 5};
+
+        // Naïve implementation
+        List<Integer> aList = new ArrayList<>(); // We create an empty list
+        for (int element : anArray) {
+            // We iterate over array's elements and add them to the list
+            aList.add(element);
+        }
+
+        // Pretty implementation
+        aList = Arrays.asList(anArray);
+
+        // Drawbacks
+        try {
+            aList.remove(0);
+        } catch (UnsupportedOperationException e) {
+            System.out.println(e.getMessage());
+        }
+
+        try {
+            aList.add(6);
+        } catch (UnsupportedOperationException e) {
+            System.out.println(e.getMessage());
+        }
+
+        int[] anotherArray = new int[] {1, 2, 3, 4, 5};
+//        List<Integer> anotherList = Arrays.asList(anotherArray);
+    }
+
+    private static void transformIntoStream() {
+        int[] anArray = new int[] {1, 2, 3, 4, 5};
+        IntStream aStream = Arrays.stream(anArray);
+
+        Integer[] anotherArray = new Integer[] {1, 2, 3, 4, 5};
+        Stream<Integer> anotherStream = Arrays.stream(anotherArray, 2, 4);
+    }
+
+    private static void sort() {
+        int[] anArray = new int[] {5, 2, 1, 4, 8};
+        Arrays.sort(anArray); // anArray is now {1, 2, 4, 5, 8}
+
+        Integer[] anotherArray = new Integer[] {5, 2, 1, 4, 8};
+        Arrays.sort(anotherArray); // anArray is now {1, 2, 4, 5, 8}
+
+        String[] yetAnotherArray = new String[] {"A", "E", "Z", "B", "C"};
+        Arrays.sort(yetAnotherArray, 1, 3, Comparator.comparing(String::toString).reversed()); // yetAnotherArray is now {"A", "Z", "E", "B", "C"}
+    }
+
+    private static void search() {
+        int[] anArray = new int[] {5, 2, 1, 4, 8};
+        for (int i = 0; i < anArray.length; i++) {
+            if (anArray[i] == 4) {
+                System.out.println("Found at index " + i);
+                break;
+            }
+        }
+
+        Arrays.sort(anArray);
+        int index = Arrays.binarySearch(anArray, 4);
+        System.out.println("Found at index " + index);
+    }
+
+    private static void merge() {
+        int[] anArray = new int[] {5, 2, 1, 4, 8};
+        int[] anotherArray = new int[] {10, 4, 9, 11, 2};
+
+        int[] resultArray = new int[anArray.length + anotherArray.length];
+        for (int i = 0; i < resultArray.length; i++) {
+            resultArray[i] = (i < anArray.length ? anArray[i] : anotherArray[i - anArray.length]);
+        }
+        for (int element : resultArray) {
+            System.out.println(element);
+        }
+
+        Arrays.setAll(resultArray, i -> (i < anArray.length ? anArray[i] : anotherArray[i - anArray.length]));
+        for (int element : resultArray) {
+            System.out.println(element);
+        }
+    }
+
+}

core-java/src/test/java/com/baeldung/modulo/ModuloUnitTest.java

@@ -0,0 +1,54 @@
+package com.baeldung.modulo;
+
+import org.junit.Test;
+import static org.assertj.core.api.Java6Assertions.*;
+
+public class ModuloUnitTest {
+
+  @Test
+  public void whenIntegerDivision_thenLosesRemainder(){
+    assertThat(11 / 4).isEqualTo(2);
+  }
+
+  @Test
+  public void whenDoubleDivision_thenKeepsRemainder(){
+    assertThat(11 / 4.0).isEqualTo(2.75);
+  }
+
+  @Test
+  public void whenModulo_thenReturnsRemainder(){
+    assertThat(11 % 4).isEqualTo(3);
+  }
+
+  @Test(expected = ArithmeticException.class)
+  public void whenDivisionByZero_thenArithmeticException(){
+    double result = 1 / 0;
+  }
+
+  @Test(expected = ArithmeticException.class)
+  public void whenModuloByZero_thenArithmeticException(){
+    double result = 1 % 0;
+  }
+
+  @Test
+  public void whenDivisorIsOddAndModulusIs2_thenResultIs1(){
+    assertThat(3 % 2).isEqualTo(1);
+  }
+
+  @Test
+  public void whenDivisorIsEvenAndModulusIs2_thenResultIs0(){
+    assertThat(4 % 2).isEqualTo(0);
+  }
+
+  @Test
+  public void whenItemsIsAddedToCircularQueue_thenNoArrayIndexOutOfBounds(){
+    int QUEUE_CAPACITY= 10;
+    int[] circularQueue = new int[QUEUE_CAPACITY];
+    int itemsInserted = 0;
+    for (int value = 0; value < 1000; value++) {
+      int writeIndex = ++itemsInserted % QUEUE_CAPACITY;
+      circularQueue[writeIndex] = value;
+    }
+  }
+
+}

core-java/src/test/java/com/baeldung/nth/root/calculator/NthRootCalculatorUnitTest.java

@@ -1,11 +1,11 @@
 package com.baeldung.nth.root.calculator;
 
+import static org.junit.Assert.assertEquals;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.InjectMocks;
-import org.mockito.runners.MockitoJUnitRunner;
-
-import static org.junit.Assert.assertEquals;
+import org.mockito.junit.MockitoJUnitRunner;
 
 @RunWith(MockitoJUnitRunner.class)
 public class NthRootCalculatorUnitTest {

core-java/src/test/java/com/baeldung/simpledateformat/SimpleDateFormatUnitTest.java

@@ -0,0 +1,59 @@
+package com.baeldung;
+
+import org.junit.Test;
+
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Locale;
+import java.util.TimeZone;
+import java.util.logging.Logger;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+
+public class SimpleDateFormatUnitTest {
+
+  private static final Logger logger = Logger.getLogger(SimpleDateFormatUnitTest.class.getName());
+
+  @Test
+  public void givenSpecificDate_whenFormatted_thenCheckFormatCorrect() throws Exception {
+    SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
+    assertEquals("24-05-1977", formatter.format(new Date(233345223232L)));
+  }
+
+  @Test
+  public void givenSpecificDate_whenFormattedUsingDateFormat_thenCheckFormatCorrect() throws Exception {
+    DateFormat formatter = DateFormat.getDateInstance(DateFormat.SHORT);
+    assertEquals("5/24/77", formatter.format(new Date(233345223232L)));
+  }
+
+  @Test
+  public void givenStringDate_whenParsed_thenCheckDateCorrect() throws Exception{
+    SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
+    Date myDate = new Date(233276400000L);
+    Date parsedDate = formatter.parse("24-05-1977");
+    assertEquals(myDate.getTime(), parsedDate.getTime());
+  }
+
+  @Test
+  public void givenFranceLocale_whenFormatted_thenCheckFormatCorrect() throws Exception{
+    SimpleDateFormat franceDateFormatter = new SimpleDateFormat("EEEEE dd-MMMMMMM-yyyy", Locale.FRANCE);
+    Date myWednesday = new Date(1539341312904L);
+    assertTrue(franceDateFormatter.format(myWednesday).startsWith("vendredi"));
+  }
+
+  @Test
+  public void given2TimeZones_whenFormatted_thenCheckTimeDifference() throws Exception {
+    Date now = new Date();
+
+    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("EEEE dd-MMM-yy HH:mm:ssZ");
+
+    simpleDateFormat.setTimeZone(TimeZone.getTimeZone("Europe/London"));
+    logger.info(simpleDateFormat.format(now));
+    //change the date format
+    simpleDateFormat.setTimeZone(TimeZone.getTimeZone("America/New_York"));
+    logger.info(simpleDateFormat.format(now));
+  }
+}

core-kotlin/README.md

@@ -37,3 +37,5 @@
 - [Kotlin with Ktor](https://www.baeldung.com/kotlin-ktor)
 - [Fuel HTTP Library with Kotlin](https://www.baeldung.com/kotlin-fuel)
 - [Introduction to Kovenant Library for Kotlin](https://www.baeldung.com/kotlin-kovenant)
+- [Converting Kotlin Data Class from JSON using GSON](https://www.baeldung.com/kotlin-json-convert-data-class)
+- [Concatenate Strings in Kotlin](https://www.baeldung.com/kotlin-concatenate-strings)

core-kotlin/src/main/kotlin/com/baeldung/interfaces/ConflictingInterfaces.kt

@@ -0,0 +1,23 @@
+package com.baeldung.interfaces
+
+interface BaseInterface {
+    fun someMethod(): String
+}
+
+interface FirstChildInterface : BaseInterface {
+    override fun someMethod(): String {
+        return("Hello, from someMethod in FirstChildInterface")
+    }
+}
+
+interface SecondChildInterface : BaseInterface {
+    override fun someMethod(): String {
+        return("Hello, from someMethod in SecondChildInterface")
+    }
+}
+
+class ChildClass : FirstChildInterface, SecondChildInterface {
+    override fun someMethod(): String {
+        return super<SecondChildInterface>.someMethod()
+    }
+}

core-kotlin/src/main/kotlin/com/baeldung/interfaces/InterfaceDelegation.kt

@@ -0,0 +1,13 @@
+package com.baeldung.interfaces
+
+interface MyInterface {
+    fun someMethod(): String
+}
+
+class MyClass() : MyInterface {
+    override fun someMethod(): String {
+        return("Hello, World!")
+    }
+}
+
+class MyDerivedClass(myInterface: MyInterface) : MyInterface by myInterface

core-kotlin/src/main/kotlin/com/baeldung/interfaces/MultipleInterfaces.kt

@@ -0,0 +1,29 @@
+package com.baeldung.interfaces
+
+interface FirstInterface {	
+    fun someMethod(): String
+	
+    fun anotherMethod(): String {
+        return("Hello, from anotherMethod in FirstInterface")
+    }
+}
+
+interface SecondInterface {
+    fun someMethod(): String {
+        return("Hello, from someMethod in SecondInterface")
+    }
+	
+    fun anotherMethod(): String {
+        return("Hello, from anotherMethod in SecondInterface")
+    }
+}
+
+class SomeClass: FirstInterface, SecondInterface {	
+    override fun someMethod(): String {
+        return("Hello, from someMethod in SomeClass")
+    }
+	
+    override fun anotherMethod(): String {
+        return("Hello, from anotherMethod in SomeClass")
+    }
+}

core-kotlin/src/main/kotlin/com/baeldung/interfaces/SimpleInterface.kt

@@ -0,0 +1,24 @@
+package com.baeldung.interfaces
+
+interface SimpleInterface {
+    val firstProp: String
+    val secondProp: String
+        get() = "Second Property"
+    fun firstMethod(): String
+    fun secondMethod(): String {
+        println("Hello, from: " + secondProp)
+        return ""
+    }
+}
+
+class SimpleClass: SimpleInterface {
+    override val firstProp: String = "First Property"
+    override val secondProp: String
+        get() = "Second Property, Overridden!"
+    override fun firstMethod(): String {
+        return("Hello, from: " + firstProp)
+    }
+    override fun secondMethod(): String {
+        return("Hello, from: " + secondProp + firstProp)
+    }
+}

core-kotlin/src/test/kotlin/com/baeldung/interfaces/InterfaceExamplesUnitTest.kt

@@ -0,0 +1,32 @@
+package com.baeldung.interfaces
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class InterfaceExamplesUnitTest {
+    @Test
+    fun givenAnInterface_whenImplemented_thenBehavesAsOverridden() {
+        val simpleClass = SimpleClass()
+        assertEquals("Hello, from: First Property", simpleClass.firstMethod())
+        assertEquals("Hello, from: Second Property, Overridden!First Property", simpleClass.secondMethod())
+    }
+
+    @Test
+    fun givenMultipleInterfaces_whenImplemented_thenBehavesAsOverridden() {
+        val someClass = SomeClass()
+        assertEquals("Hello, from someMethod in SomeClass", someClass.someMethod())
+        assertEquals("Hello, from anotherMethod in SomeClass", someClass.anotherMethod())
+    }
+
+    @Test
+    fun givenConflictingInterfaces_whenImplemented_thenBehavesAsOverridden() {
+        val childClass = ChildClass()
+        assertEquals("Hello, from someMethod in SecondChildInterface", childClass.someMethod())
+    }
+
+    @Test
+    fun givenAnInterface_whenImplemented_thenBehavesAsDelegated() {
+        val myClass = MyClass()
+        assertEquals("Hello, World!", MyDerivedClass(myClass).someMethod())
+    }
+}

gradle/junit5/build.gradle

@@ -0,0 +1,25 @@
+plugins {
+    // Apply the java-library plugin to add support for Java Library
+    id 'java-library'
+}
+
+dependencies {
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.1'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.1'
+    
+    // Only necessary for JUnit 3 and 4 tests
+    testCompileOnly 'junit:junit:4.12' 
+    testRuntimeOnly 'org.junit.vintage:junit-vintage-engine:5.3.1' 
+    
+}
+
+repositories {
+    jcenter()
+}
+
+test {
+    useJUnitPlatform {
+    	includeTags 'fast'
+        excludeTags 'slow'
+    }
+}

gradle/junit5/src/test/java/com/example/CalculatorJUnit4Test.java

@@ -0,0 +1,12 @@
+package com.example;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class CalculatorJUnit4Test {
+    @Test
+    public void testAdd() {
+        assertEquals(42, Integer.sum(19, 23));
+    }
+}

gradle/junit5/src/test/java/com/example/CalculatorJUnit5Test.java

@@ -0,0 +1,36 @@
+package com.example;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;;
+
+public class CalculatorJUnit5Test {
+
+    @Tag("fast")
+    @Test
+    public void testAdd() {
+        assertEquals(42, Integer.sum(19, 23));
+    }
+
+    @Tag("slow")
+    @Test
+    public void testAddMaxInteger() {
+        assertEquals(2147483646, Integer.sum(2147183646, 300000));
+    }
+
+    @Tag("fast")
+    @Test
+    public void testAddZero() {
+        assertEquals(21, Integer.sum(21, 0));
+    }
+
+    @Tag("fast")
+    @Test
+    public void testDivide() {
+        assertThrows(ArithmeticException.class, () -> {
+            Integer.divideUnsigned(42, 0);
+        });
+    }
+}

gradle/settings.gradle

@@ -5,6 +5,6 @@ include 'greeting-library'
 include 'greeting-library-java'
 include 'greeter'
 include 'gradletaskdemo'
-
+include 'junit5'
 
 println 'This will be executed during the initialization phase.'

guava-collections/README.md

@@ -0,0 +1,23 @@
+=========
+
+## Guava and Hamcrest Cookbooks and Examples
+
+
+### Relevant Articles: 
+- [Guava Collections Cookbook](http://www.baeldung.com/guava-collections)
+- [Guava Ordering Cookbook](http://www.baeldung.com/guava-order)
+- [Hamcrest Collections Cookbook](http://www.baeldung.com/hamcrest-collections-arrays)
+- [Partition a List in Java](http://www.baeldung.com/java-list-split)
+- [Filtering and Transforming Collections in Guava](http://www.baeldung.com/guava-filter-and-transform-a-collection)
+- [Guava – Join and Split Collections](http://www.baeldung.com/guava-joiner-and-splitter-tutorial)
+- [Guava – Lists](http://www.baeldung.com/guava-lists)
+- [Guava – Sets](http://www.baeldung.com/guava-sets)
+- [Guava – Maps](http://www.baeldung.com/guava-maps)
+- [Guide to Guava Multimap](http://www.baeldung.com/guava-multimap)
+- [Guide to Guava RangeSet](http://www.baeldung.com/guava-rangeset)
+- [Guide to Guava RangeMap](http://www.baeldung.com/guava-rangemap)
+- [Guide to Guava MinMaxPriorityQueue and EvictingQueue](http://www.baeldung.com/guava-minmax-priority-queue-and-evicting-queue)
+- [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
+- [Guava Set + Function = Map](http://www.baeldung.com/guava-set-function-map-tutorial)
+- [Guide to Guava Table](http://www.baeldung.com/guava-table)
+- [Guide to Guava ClassToInstanceMap](http://www.baeldung.com/guava-class-to-instance-map)

guava-collections/pom.xml

@@ -0,0 +1,66 @@
+<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>guava-collections</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>guava-collections</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-java</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-java</relativePath>
+    </parent>
+
+    <dependencies>
+        <!-- utils -->
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-collections4</artifactId>
+            <version>${commons-collections4.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>${commons-lang3.version}</version>
+        </dependency>
+        <!-- test scoped -->
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <!-- https://mvnrepository.com/artifact/org.hamcrest/java-hamcrest -->
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>java-hamcrest</artifactId>
+            <version>${java-hamcrest.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <finalName>guava</finalName>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+    </build>
+
+    <properties>
+        <!-- util -->
+        <guava.version>24.0-jre</guava.version>
+        <commons-lang3.version>3.5</commons-lang3.version>
+        <commons-collections4.version>4.1</commons-collections4.version>
+
+        <!-- testing -->
+        <assertj.version>3.6.1</assertj.version>
+        <java-hamcrest.version>2.0.0.0</java-hamcrest.version>
+    </properties>
+
+</project>

guava-collections/src/test/resources/.gitignore

@@ -0,0 +1,13 @@
+*.class
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+
+# Packaged files #
+*.jar
+*.war
+*.ear

guava-collections/src/test/resources/test.out

@@ -0,0 +1 @@
+John Jane Adam Tom 

guava-collections/src/test/resources/test1.in

@@ -0,0 +1 @@
+Hello world

guava-collections/src/test/resources/test1_1.in

@@ -0,0 +1 @@
+Test

guava-collections/src/test/resources/test2.in

@@ -0,0 +1,4 @@
+John
+Jane
+Adam
+Tom

guava-collections/src/test/resources/test_copy.in

@@ -0,0 +1 @@
+Hello world

guava/README.md

@@ -4,33 +4,16 @@
 
 
 ### Relevant Articles: 
-- [Guava Collections Cookbook](http://www.baeldung.com/guava-collections)
-- [Guava Ordering Cookbook](http://www.baeldung.com/guava-order)
 - [Guava Functional Cookbook](http://www.baeldung.com/guava-functions-predicates)
-- [Hamcrest Collections Cookbook](http://www.baeldung.com/hamcrest-collections-arrays)
-- [Partition a List in Java](http://www.baeldung.com/java-list-split)
-- [Filtering and Transforming Collections in Guava](http://www.baeldung.com/guava-filter-and-transform-a-collection)
-- [Guava – Join and Split Collections](http://www.baeldung.com/guava-joiner-and-splitter-tutorial)
 - [Guava – Write to File, Read from File](http://www.baeldung.com/guava-write-to-file-read-from-file)
-- [Guava – Lists](http://www.baeldung.com/guava-lists)
-- [Guava – Sets](http://www.baeldung.com/guava-sets)
-- [Guava – Maps](http://www.baeldung.com/guava-maps)
-- [Guava Set + Function = Map](http://www.baeldung.com/guava-set-function-map-tutorial)
 - [Guide to Guava’s Ordering](http://www.baeldung.com/guava-ordering)
 - [Guide to Guava’s PreConditions](http://www.baeldung.com/guava-preconditions)
 - [Introduction to Guava CacheLoader](http://www.baeldung.com/guava-cacheloader)
 - [Introduction to Guava Memoizer](http://www.baeldung.com/guava-memoizer)
 - [Guide to Guava’s EventBus](http://www.baeldung.com/guava-eventbus)
-- [Guide to Guava Multimap](http://www.baeldung.com/guava-multimap)
-- [Guide to Guava RangeSet](http://www.baeldung.com/guava-rangeset)
-- [Guide to Guava RangeMap](http://www.baeldung.com/guava-rangemap)
-- [Guide to Guava Table](http://www.baeldung.com/guava-table)
 - [Guide to Guava’s Reflection Utilities](http://www.baeldung.com/guava-reflection)
-- [Guide to Guava ClassToInstanceMap](http://www.baeldung.com/guava-class-to-instance-map)
-- [Guide to Guava MinMaxPriorityQueue and EvictingQueue](http://www.baeldung.com/guava-minmax-priority-queue-and-evicting-queue)
 - [Guide to Mathematical Utilities in Guava](http://www.baeldung.com/guava-math)
 - [Bloom Filter in Java using Guava](http://www.baeldung.com/guava-bloom-filter)
 - [Using Guava CountingOutputStream](http://www.baeldung.com/guava-counting-outputstream)
 - [Hamcrest Text Matchers](http://www.baeldung.com/hamcrest-text-matchers)
 - [Quick Guide to the Guava RateLimiter](http://www.baeldung.com/guava-rate-limiter)
-- [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)

guava/pom.xml

@@ -14,12 +14,6 @@
     </parent>
 
     <dependencies>
-        <!-- utils -->
-        <dependency>
-            <groupId>org.apache.commons</groupId>
-            <artifactId>commons-collections4</artifactId>
-            <version>${commons-collections4.version}</version>
-        </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
@@ -56,7 +50,6 @@
         <!-- util -->
         <guava.version>24.0-jre</guava.version>
         <commons-lang3.version>3.5</commons-lang3.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
 
         <!-- testing -->
         <assertj.version>3.6.1</assertj.version>

hibernate5/README.md

@@ -16,3 +16,4 @@
 - [Hibernate Entity Lifecycle](https://www.baeldung.com/hibernate-entity-lifecycle)
 - [Mapping A Hibernate Query to a Custom Class](https://www.baeldung.com/hibernate-query-to-custom-class)
 - [@JoinColumn Annotation Explained](https://www.baeldung.com/jpa-join-column)
+- [Hibernate 5 Naming Strategy Configuration](https://www.baeldung.com/hibernate-naming-strategy)

hibernate5/pom.xml

@@ -44,6 +44,11 @@
             <artifactId>mariaDB4j</artifactId>
             <version>${mariaDB4j.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-testing</artifactId>
+            <version>5.2.2.Final</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -57,7 +62,7 @@
     </build>
 
     <properties>
-        <hibernate.version>5.3.2.Final</hibernate.version>
+        <hibernate.version>5.3.6.Final</hibernate.version>
         <mysql.version>6.0.6</mysql.version>
         <mariaDB4j.version>2.2.3</mariaDB4j.version>
         <h2database.version>1.4.196</h2database.version>

hibernate5/src/main/java/com/baeldung/hibernate/HibernateUtil.java

@@ -5,6 +5,8 @@ import java.io.IOException;
 import java.net.URL;
 import java.util.Properties;
 
+import com.baeldung.hibernate.customtypes.LocalDateStringType;
+import com.baeldung.hibernate.customtypes.OfficeEmployee;
 import com.baeldung.hibernate.entities.DeptEmployee;
 import com.baeldung.hibernate.optimisticlocking.OptimisticLockingCourse;
 import com.baeldung.hibernate.optimisticlocking.OptimisticLockingStudent;
@@ -18,8 +20,10 @@ import com.baeldung.hibernate.pojo.inheritance.*;
 import org.apache.commons.lang3.StringUtils;
 import org.hibernate.SessionFactory;
 import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataBuilder;
 import org.hibernate.boot.MetadataSources;
 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.Configuration;
 import org.hibernate.service.ServiceRegistry;
 
 import com.baeldung.hibernate.pojo.Course;
@@ -66,6 +70,7 @@ public class HibernateUtil {
 
     private static SessionFactory makeSessionFactory(ServiceRegistry serviceRegistry) {
         MetadataSources metadataSources = new MetadataSources(serviceRegistry);
+
         metadataSources.addPackage("com.baeldung.hibernate.pojo");
         metadataSources.addAnnotatedClass(Employee.class);
         metadataSources.addAnnotatedClass(Phone.class);
@@ -102,8 +107,12 @@ public class HibernateUtil {
         metadataSources.addAnnotatedClass(com.baeldung.hibernate.entities.Department.class);
         metadataSources.addAnnotatedClass(OptimisticLockingCourse.class);
         metadataSources.addAnnotatedClass(OptimisticLockingStudent.class);
+        metadataSources.addAnnotatedClass(OfficeEmployee.class);
+
+        Metadata metadata = metadataSources.getMetadataBuilder()
+                .applyBasicType(LocalDateStringType.INSTANCE)
+                .build();
 
-        Metadata metadata = metadataSources.buildMetadata();
         return metadata.getSessionFactoryBuilder()
                 .build();
 

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/Address.java

@@ -0,0 +1,69 @@
+package com.baeldung.hibernate.customtypes;
+
+import java.util.Objects;
+
+public class Address {
+
+    private String addressLine1;
+    private String addressLine2;
+    private String city;
+    private String country;
+    private int zipCode;
+
+    public String getAddressLine1() {
+        return addressLine1;
+    }
+
+    public String getAddressLine2() {
+        return addressLine2;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public String getCountry() {
+        return country;
+    }
+
+    public int getZipCode() {
+        return zipCode;
+    }
+
+    public void setAddressLine1(String addressLine1) {
+        this.addressLine1 = addressLine1;
+    }
+
+    public void setAddressLine2(String addressLine2) {
+        this.addressLine2 = addressLine2;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+
+    public void setCountry(String country) {
+        this.country = country;
+    }
+
+    public void setZipCode(int zipCode) {
+        this.zipCode = zipCode;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Address address = (Address) o;
+        return zipCode == address.zipCode &&
+                Objects.equals(addressLine1, address.addressLine1) &&
+                Objects.equals(addressLine2, address.addressLine2) &&
+                Objects.equals(city, address.city) &&
+                Objects.equals(country, address.country);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(addressLine1, addressLine2, city, country, zipCode);
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/AddressType.java

@@ -0,0 +1,169 @@
+package com.baeldung.hibernate.customtypes;
+
+import org.hibernate.HibernateException;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.type.IntegerType;
+import org.hibernate.type.StringType;
+import org.hibernate.type.Type;
+import org.hibernate.usertype.CompositeUserType;
+
+import java.io.Serializable;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Types;
+import java.util.Objects;
+
+public class AddressType implements CompositeUserType {
+
+    @Override
+    public String[] getPropertyNames() {
+        return new String[]{"addressLine1", "addressLine2",
+                "city", "country", "zipcode"};
+    }
+
+    @Override
+    public Type[] getPropertyTypes() {
+        return new Type[]{StringType.INSTANCE, StringType.INSTANCE,
+                StringType.INSTANCE, StringType.INSTANCE, IntegerType.INSTANCE};
+    }
+
+    @Override
+    public Object getPropertyValue(Object component, int property) throws HibernateException {
+
+        Address empAdd = (Address) component;
+
+        switch (property) {
+            case 0:
+                return empAdd.getAddressLine1();
+            case 1:
+                return empAdd.getAddressLine2();
+            case 2:
+                return empAdd.getCity();
+            case 3:
+                return empAdd.getCountry();
+            case 4:
+                return Integer.valueOf(empAdd.getZipCode());
+        }
+
+        throw new IllegalArgumentException(property +
+                " is an invalid property index for class type " +
+                component.getClass().getName());
+    }
+
+    @Override
+    public void setPropertyValue(Object component, int property, Object value) throws HibernateException {
+
+        Address empAdd = (Address) component;
+
+        switch (property) {
+            case 0:
+                empAdd.setAddressLine1((String) value);
+            case 1:
+                empAdd.setAddressLine2((String) value);
+            case 2:
+                empAdd.setCity((String) value);
+            case 3:
+                empAdd.setCountry((String) value);
+            case 4:
+                empAdd.setZipCode((Integer) value);
+        }
+
+        throw new IllegalArgumentException(property +
+                " is an invalid property index for class type " +
+                component.getClass().getName());
+
+    }
+
+    @Override
+    public Class returnedClass() {
+        return Address.class;
+    }
+
+    @Override
+    public boolean equals(Object x, Object y) throws HibernateException {
+        if (x == y)
+            return true;
+
+        if (Objects.isNull(x) || Objects.isNull(y))
+            return false;
+
+        return x.equals(y);
+    }
+
+    @Override
+    public int hashCode(Object x) throws HibernateException {
+        return x.hashCode();
+    }
+
+    @Override
+    public Object nullSafeGet(ResultSet rs, String[] names, SharedSessionContractImplementor session, Object owner) throws HibernateException, SQLException {
+
+        Address empAdd = new Address();
+        empAdd.setAddressLine1(rs.getString(names[0]));
+
+        if (rs.wasNull())
+            return null;
+
+        empAdd.setAddressLine2(rs.getString(names[1]));
+        empAdd.setCity(rs.getString(names[2]));
+        empAdd.setCountry(rs.getString(names[3]));
+        empAdd.setZipCode(rs.getInt(names[4]));
+
+        return empAdd;
+    }
+
+    @Override
+    public void nullSafeSet(PreparedStatement st, Object value, int index, SharedSessionContractImplementor session) throws HibernateException, SQLException {
+
+        if (Objects.isNull(value))
+            st.setNull(index, Types.VARCHAR);
+        else {
+
+            Address empAdd = (Address) value;
+            st.setString(index, empAdd.getAddressLine1());
+            st.setString(index + 1, empAdd.getAddressLine2());
+            st.setString(index + 2, empAdd.getCity());
+            st.setString(index + 3, empAdd.getCountry());
+            st.setInt(index + 4, empAdd.getZipCode());
+        }
+    }
+
+    @Override
+    public Object deepCopy(Object value) throws HibernateException {
+
+        if (Objects.isNull(value))
+            return null;
+
+        Address oldEmpAdd = (Address) value;
+        Address newEmpAdd = new Address();
+
+        newEmpAdd.setAddressLine1(oldEmpAdd.getAddressLine1());
+        newEmpAdd.setAddressLine2(oldEmpAdd.getAddressLine2());
+        newEmpAdd.setCity(oldEmpAdd.getCity());
+        newEmpAdd.setCountry(oldEmpAdd.getCountry());
+        newEmpAdd.setZipCode(oldEmpAdd.getZipCode());
+
+        return newEmpAdd;
+    }
+
+    @Override
+    public boolean isMutable() {
+        return true;
+    }
+
+    @Override
+    public Serializable disassemble(Object value, SharedSessionContractImplementor session) throws HibernateException {
+        return (Serializable) deepCopy(value);
+    }
+
+    @Override
+    public Object assemble(Serializable cached, SharedSessionContractImplementor session, Object owner) throws HibernateException {
+        return deepCopy(cached);
+    }
+
+    @Override
+    public Object replace(Object original, Object target, SharedSessionContractImplementor session, Object owner) throws HibernateException {
+        return original;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/LocalDateStringJavaDescriptor.java

@@ -0,0 +1,51 @@
+package com.baeldung.hibernate.customtypes;
+
+import org.hibernate.type.LocalDateType;
+import org.hibernate.type.descriptor.WrapperOptions;
+import org.hibernate.type.descriptor.java.AbstractTypeDescriptor;
+import org.hibernate.type.descriptor.java.ImmutableMutabilityPlan;
+import org.hibernate.type.descriptor.java.MutabilityPlan;
+
+import java.time.LocalDate;
+
+public class LocalDateStringJavaDescriptor extends AbstractTypeDescriptor<LocalDate> {
+
+    public static final LocalDateStringJavaDescriptor INSTANCE = new LocalDateStringJavaDescriptor();
+
+    public LocalDateStringJavaDescriptor() {
+        super(LocalDate.class, ImmutableMutabilityPlan.INSTANCE);
+    }
+
+    @Override
+    public String toString(LocalDate value) {
+        return LocalDateType.FORMATTER.format(value);
+    }
+
+    @Override
+    public LocalDate fromString(String string) {
+        return LocalDate.from(LocalDateType.FORMATTER.parse(string));
+    }
+
+    @Override
+    public <X> X unwrap(LocalDate value, Class<X> type, WrapperOptions options) {
+
+        if (value == null)
+            return null;
+
+        if (String.class.isAssignableFrom(type))
+            return (X) LocalDateType.FORMATTER.format(value);
+
+        throw unknownUnwrap(type);
+    }
+
+    @Override
+    public <X> LocalDate wrap(X value, WrapperOptions options) {
+        if (value == null)
+            return null;
+
+        if(String.class.isInstance(value))
+            return LocalDate.from(LocalDateType.FORMATTER.parse((CharSequence) value));
+
+        throw unknownWrap(value.getClass());
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/LocalDateStringType.java

@@ -0,0 +1,34 @@
+package com.baeldung.hibernate.customtypes;
+
+import org.hibernate.dialect.Dialect;
+import org.hibernate.type.AbstractSingleColumnStandardBasicType;
+import org.hibernate.type.DiscriminatorType;
+import org.hibernate.type.descriptor.java.LocalDateJavaDescriptor;
+import org.hibernate.type.descriptor.sql.VarcharTypeDescriptor;
+
+import java.time.LocalDate;
+
+public class LocalDateStringType extends AbstractSingleColumnStandardBasicType<LocalDate> implements DiscriminatorType<LocalDate> {
+
+    public static final LocalDateStringType INSTANCE = new LocalDateStringType();
+
+    public LocalDateStringType() {
+        super(VarcharTypeDescriptor.INSTANCE, LocalDateStringJavaDescriptor.INSTANCE);
+    }
+
+    @Override
+    public String getName() {
+        return "LocalDateString";
+    }
+
+    @Override
+    public LocalDate stringToObject(String xml) throws Exception {
+        return fromString(xml);
+    }
+
+    @Override
+    public String objectToSQLString(LocalDate value, Dialect dialect) throws Exception {
+        return '\'' + toString(value) + '\'';
+    }
+
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/OfficeEmployee.java

@@ -0,0 +1,88 @@
+package com.baeldung.hibernate.customtypes;
+
+import com.baeldung.hibernate.pojo.Phone;
+import org.hibernate.annotations.Columns;
+import org.hibernate.annotations.Parameter;
+import org.hibernate.annotations.Type;
+import org.hibernate.annotations.TypeDef;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Table;
+import java.time.LocalDate;
+
+@TypeDef(name = "PhoneNumber",
+        typeClass = PhoneNumberType.class,
+        defaultForType = PhoneNumber.class)
+@Entity
+@Table(name = "OfficeEmployee")
+public class OfficeEmployee {
+
+    @Id
+    @GeneratedValue
+    private long id;
+
+    @Column
+    @Type(type = "LocalDateString")
+    private LocalDate dateOfJoining;
+
+    @Columns(columns = {@Column(name = "country_code"),
+            @Column(name = "city_code"),
+            @Column(name = "number")})
+    private PhoneNumber employeeNumber;
+
+    @Columns(columns = {@Column(name = "address_line_1"),
+            @Column(name = "address_line_2"),
+            @Column(name = "city"), @Column(name = "country"),
+            @Column(name = "zip_code")})
+    @Type(type = "com.baeldung.hibernate.customtypes.AddressType")
+    private Address empAddress;
+
+    @Type(type = "com.baeldung.hibernate.customtypes.SalaryType",
+            parameters = {@Parameter(name = "currency", value = "USD")})
+    @Columns(columns = {@Column(name = "amount"),
+            @Column(name = "currency")})
+    private Salary salary;
+
+    public Salary getSalary() {
+        return salary;
+    }
+
+    public void setSalary(Salary salary) {
+        this.salary = salary;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    public LocalDate getDateOfJoining() {
+        return dateOfJoining;
+    }
+
+    public void setDateOfJoining(LocalDate dateOfJoining) {
+        this.dateOfJoining = dateOfJoining;
+    }
+
+    public PhoneNumber getEmployeeNumber() {
+        return employeeNumber;
+    }
+
+    public void setEmployeeNumber(PhoneNumber employeeNumber) {
+        this.employeeNumber = employeeNumber;
+    }
+
+    public Address getEmpAddress() {
+        return empAddress;
+    }
+
+    public void setEmpAddress(Address empAddress) {
+        this.empAddress = empAddress;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/PhoneNumber.java

@@ -0,0 +1,43 @@
+package com.baeldung.hibernate.customtypes;
+
+import java.util.Objects;
+
+public final class PhoneNumber {
+
+    private final int countryCode;
+    private final int cityCode;
+    private final int number;
+
+    public PhoneNumber(int countryCode, int cityCode, int number) {
+        this.countryCode = countryCode;
+        this.cityCode = cityCode;
+        this.number = number;
+    }
+
+    public int getCountryCode() {
+        return countryCode;
+    }
+
+    public int getCityCode() {
+        return cityCode;
+    }
+
+    public int getNumber() {
+        return number;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        PhoneNumber that = (PhoneNumber) o;
+        return countryCode == that.countryCode &&
+                cityCode == that.cityCode &&
+                number == that.number;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(countryCode, cityCode, number);
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/PhoneNumberType.java

@@ -0,0 +1,98 @@
+package com.baeldung.hibernate.customtypes;
+
+import org.hibernate.HibernateException;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.usertype.UserType;
+
+import java.io.Serializable;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Types;
+import java.util.Objects;
+
+
+public class PhoneNumberType implements UserType {
+    @Override
+    public int[] sqlTypes() {
+        return new int[]{Types.INTEGER, Types.INTEGER, Types.INTEGER};
+    }
+
+    @Override
+    public Class returnedClass() {
+        return PhoneNumber.class;
+    }
+
+    @Override
+    public boolean equals(Object x, Object y) throws HibernateException {
+        if (x == y)
+            return true;
+        if (Objects.isNull(x) || Objects.isNull(y))
+            return false;
+
+        return x.equals(y);
+    }
+
+    @Override
+    public int hashCode(Object x) throws HibernateException {
+        return x.hashCode();
+    }
+
+    @Override
+    public Object nullSafeGet(ResultSet rs, String[] names, SharedSessionContractImplementor session, Object owner) throws HibernateException, SQLException {
+        int countryCode = rs.getInt(names[0]);
+
+        if (rs.wasNull())
+            return null;
+
+        int cityCode = rs.getInt(names[1]);
+        int number = rs.getInt(names[2]);
+        PhoneNumber employeeNumber = new PhoneNumber(countryCode, cityCode, number);
+
+        return employeeNumber;
+    }
+
+    @Override
+    public void nullSafeSet(PreparedStatement st, Object value, int index, SharedSessionContractImplementor session) throws HibernateException, SQLException {
+
+        if (Objects.isNull(value)) {
+            st.setNull(index, Types.INTEGER);
+        } else {
+            PhoneNumber employeeNumber = (PhoneNumber) value;
+            st.setInt(index,employeeNumber.getCountryCode());
+            st.setInt(index+1,employeeNumber.getCityCode());
+            st.setInt(index+2,employeeNumber.getNumber());
+        }
+    }
+
+    @Override
+    public Object deepCopy(Object value) throws HibernateException {
+        if (Objects.isNull(value))
+            return null;
+
+        PhoneNumber empNumber = (PhoneNumber) value;
+        PhoneNumber newEmpNumber = new PhoneNumber(empNumber.getCountryCode(),empNumber.getCityCode(),empNumber.getNumber());
+
+        return newEmpNumber;
+    }
+
+    @Override
+    public boolean isMutable() {
+        return false;
+    }
+
+    @Override
+    public Serializable disassemble(Object value) throws HibernateException {
+        return (Serializable) value;
+    }
+
+    @Override
+    public Object assemble(Serializable cached, Object owner) throws HibernateException {
+        return cached;
+    }
+
+    @Override
+    public Object replace(Object original, Object target, Object owner) throws HibernateException {
+        return original;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/Salary.java

@@ -0,0 +1,39 @@
+package com.baeldung.hibernate.customtypes;
+
+import java.util.Objects;
+
+public class Salary {
+
+    private Long amount;
+    private String currency;
+
+    public Long getAmount() {
+        return amount;
+    }
+
+    public void setAmount(Long amount) {
+        this.amount = amount;
+    }
+
+    public String getCurrency() {
+        return currency;
+    }
+
+    public void setCurrency(String currency) {
+        this.currency = currency;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Salary salary = (Salary) o;
+        return Objects.equals(amount, salary.amount) &&
+                Objects.equals(currency, salary.currency);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(amount, currency);
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/SalaryCurrencyConvertor.java

@@ -0,0 +1,15 @@
+package com.baeldung.hibernate.customtypes;
+
+public class SalaryCurrencyConvertor {
+
+    public static Long convert(Long amount, String oldCurr, String newCurr){
+        if (newCurr.equalsIgnoreCase(oldCurr))
+            return amount;
+
+        return convertTo();
+    }
+
+    private static Long convertTo() {
+        return 10L;
+    }
+}

hibernate5/src/main/java/com/baeldung/hibernate/customtypes/SalaryType.java

@@ -0,0 +1,161 @@
+package com.baeldung.hibernate.customtypes;
+
+import org.hibernate.HibernateException;
+import org.hibernate.engine.spi.SharedSessionContractImplementor;
+import org.hibernate.type.LongType;
+import org.hibernate.type.StringType;
+import org.hibernate.type.Type;
+import org.hibernate.usertype.CompositeUserType;
+import org.hibernate.usertype.DynamicParameterizedType;
+
+import java.io.Serializable;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Types;
+import java.util.Objects;
+import java.util.Properties;
+
+public class SalaryType implements CompositeUserType, DynamicParameterizedType {
+
+    private String localCurrency;
+
+    @Override
+    public String[] getPropertyNames() {
+        return new String[]{"amount", "currency"};
+    }
+
+    @Override
+    public Type[] getPropertyTypes() {
+        return new Type[]{LongType.INSTANCE, StringType.INSTANCE};
+    }
+
+    @Override
+    public Object getPropertyValue(Object component, int property) throws HibernateException {
+
+        Salary salary = (Salary) component;
+
+        switch (property) {
+            case 0:
+                return salary.getAmount();
+            case 1:
+                return salary.getCurrency();
+        }
+
+        throw new IllegalArgumentException(property +
+                " is an invalid property index for class type " +
+                component.getClass().getName());
+
+    }
+
+
+    @Override
+    public void setPropertyValue(Object component, int property, Object value) throws HibernateException {
+
+        Salary salary = (Salary) component;
+
+        switch (property) {
+            case 0:
+                salary.setAmount((Long) value);
+            case 1:
+                salary.setCurrency((String) value);
+        }
+
+        throw new IllegalArgumentException(property +
+                " is an invalid property index for class type " +
+                component.getClass().getName());
+
+    }
+
+    @Override
+    public Class returnedClass() {
+        return Salary.class;
+    }
+
+    @Override
+    public boolean equals(Object x, Object y) throws HibernateException {
+
+        if (x == y)
+            return true;
+
+        if (Objects.isNull(x) || Objects.isNull(y))
+            return false;
+
+        return x.equals(y);
+
+    }
+
+    @Override
+    public int hashCode(Object x) throws HibernateException {
+        return x.hashCode();
+    }
+
+    @Override
+    public Object nullSafeGet(ResultSet rs, String[] names, SharedSessionContractImplementor session, Object owner) throws HibernateException, SQLException {
+
+        Salary salary = new Salary();
+        salary.setAmount(rs.getLong(names[0]));
+
+        if (rs.wasNull())
+            return null;
+
+        salary.setCurrency(rs.getString(names[1]));
+
+        return salary;
+    }
+
+    @Override
+    public void nullSafeSet(PreparedStatement st, Object value, int index, SharedSessionContractImplementor session) throws HibernateException, SQLException {
+
+
+        if (Objects.isNull(value))
+            st.setNull(index, Types.BIGINT);
+        else {
+
+            Salary salary = (Salary) value;
+            st.setLong(index, SalaryCurrencyConvertor.convert(salary.getAmount(),
+                    salary.getCurrency(), localCurrency));
+            st.setString(index + 1, salary.getCurrency());
+        }
+    }
+
+    @Override
+    public Object deepCopy(Object value) throws HibernateException {
+
+        if (Objects.isNull(value))
+            return null;
+
+        Salary oldSal = (Salary) value;
+        Salary newSal = new Salary();
+
+        newSal.setAmount(oldSal.getAmount());
+        newSal.setCurrency(oldSal.getCurrency());
+
+        return newSal;
+    }
+
+    @Override
+    public boolean isMutable() {
+        return true;
+    }
+
+    @Override
+    public Serializable disassemble(Object value, SharedSessionContractImplementor session) throws HibernateException {
+        return (Serializable) deepCopy(value);
+    }
+
+    @Override
+    public Object assemble(Serializable cached, SharedSessionContractImplementor session, Object owner) throws HibernateException {
+        return deepCopy(cached);
+    }
+
+    @Override
+    public Object replace(Object original, Object target, SharedSessionContractImplementor session, Object owner) throws HibernateException {
+        return original;
+    }
+
+    @Override
+    public void setParameterValues(Properties parameters) {
+        this.localCurrency = parameters.getProperty("currency");
+    }
+}

hibernate5/src/test/java/com/baeldung/hibernate/customtypes/HibernateCustomTypesUnitTest.java

@@ -0,0 +1,90 @@
+package com.baeldung.hibernate.customtypes;
+
+import com.baeldung.hibernate.HibernateUtil;
+import org.hibernate.SessionFactory;
+import org.hibernate.query.Query;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.time.LocalDate;
+
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+
+public class HibernateCustomTypesUnitTest {
+
+    @Test
+    public void givenEmployee_whenSavedWithCustomTypes_thenEntityIsSaved() throws IOException {
+
+        final OfficeEmployee e = new OfficeEmployee();
+        e.setDateOfJoining(LocalDate.now());
+
+        PhoneNumber number = new PhoneNumber(1, 222, 8781902);
+        e.setEmployeeNumber(number);
+
+        Address empAdd = new Address();
+        empAdd.setAddressLine1("Street");
+        empAdd.setAddressLine2("Area");
+        empAdd.setCity("City");
+        empAdd.setCountry("Country");
+        empAdd.setZipCode(100);
+
+        e.setEmpAddress(empAdd);
+
+        Salary empSalary = new Salary();
+        empSalary.setAmount(1000L);
+        empSalary.setCurrency("USD");
+        e.setSalary(empSalary);
+
+        doInHibernate(this::sessionFactory, session -> {
+            session.save(e);
+            boolean contains = session.contains(e);
+            Assert.assertTrue(contains);
+        });
+
+    }
+
+    @Test
+    public void givenEmployee_whenCustomTypeInQuery_thenReturnEntity() throws IOException {
+
+        final OfficeEmployee e = new OfficeEmployee();
+        e.setDateOfJoining(LocalDate.now());
+
+        PhoneNumber number = new PhoneNumber(1, 222, 8781902);
+        e.setEmployeeNumber(number);
+
+        Address empAdd = new Address();
+        empAdd.setAddressLine1("Street");
+        empAdd.setAddressLine2("Area");
+        empAdd.setCity("City");
+        empAdd.setCountry("Country");
+        empAdd.setZipCode(100);
+        e.setEmpAddress(empAdd);
+
+        Salary empSalary = new Salary();
+        empSalary.setAmount(1000L);
+        empSalary.setCurrency("USD");
+        e.setSalary(empSalary);
+
+        doInHibernate(this::sessionFactory, session -> {
+            session.save(e);
+
+            Query query = session.createQuery("FROM OfficeEmployee OE WHERE OE.empAddress.zipcode = :pinCode");
+            query.setParameter("pinCode",100);
+            int size = query.list().size();
+
+            Assert.assertEquals(1, size);
+        });
+
+    }
+
+    private SessionFactory sessionFactory() {
+        try {
+            return HibernateUtil.getSessionFactory("hibernate-customtypes.properties");
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return null;
+    }
+}

hibernate5/src/test/resources/hibernate-customtypes.properties

@@ -0,0 +1,10 @@
+hibernate.connection.driver_class=org.postgresql.Driver
+hibernate.connection.url=jdbc:postgresql://localhost:5432/test
+hibernate.connection.username=postgres
+hibernate.connection.password=thule
+hibernate.connection.autocommit=true
+jdbc.password=thule
+
+hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
+hibernate.show_sql=true
+hibernate.hbm2ddl.auto=create-drop

jackson/src/test/java/com/baeldung/jackson/xmlToJson/XmlToJsonUnitTest.java

@@ -1,7 +1,5 @@
 package com.baeldung.jackson.xmlToJson;
 
-
-import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
@@ -14,43 +12,32 @@ import java.io.IOException;
 public class XmlToJsonUnitTest {
 
     @Test
-    public void givenAnXML_whenUseDataBidingToConvertToJSON_thenReturnDataOK() {
+    public void givenAnXML_whenUseDataBidingToConvertToJSON_thenReturnDataOK() throws IOException{
         String flowerXML = "<Flower><name>Poppy</name><color>RED</color><petals>9</petals></Flower>";
 
-        try {
-            XmlMapper xmlMapper = new XmlMapper();
-            Flower poppy = xmlMapper.readValue(flowerXML, Flower.class);
+        XmlMapper xmlMapper = new XmlMapper();
+        Flower poppy = xmlMapper.readValue(flowerXML, Flower.class);
 
-            assertEquals(poppy.getName(), "Poppy");
-            assertEquals(poppy.getColor(), Color.RED);
-            assertEquals(poppy.getPetals(), new Integer(9));
+        assertEquals(poppy.getName(), "Poppy");
+        assertEquals(poppy.getColor(), Color.RED);
+        assertEquals(poppy.getPetals(), new Integer(9));
 
-            ObjectMapper mapper = new ObjectMapper();
-            String json = mapper.writeValueAsString(poppy);
+        ObjectMapper mapper = new ObjectMapper();
+        String json = mapper.writeValueAsString(poppy);
 
-            assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":9}");
-            System.out.println(json);
-        } catch(IOException e) {
-            e.printStackTrace();
-        }
+        assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":9}");
     }
 
     @Test
-    public void givenAnXML_whenUseATreeConvertToJSON_thenReturnDataOK() {
+    public void givenAnXML_whenUseATreeConvertToJSON_thenReturnDataOK() throws IOException {
         String flowerXML = "<Flower><name>Poppy</name><color>RED</color><petals>9</petals></Flower>";
 
-        try {
-            XmlMapper xmlMapper = new XmlMapper();
-            JsonNode node = xmlMapper.readTree(flowerXML.getBytes());
+        XmlMapper xmlMapper = new XmlMapper();
+        JsonNode node = xmlMapper.readTree(flowerXML.getBytes());
 
-            ObjectMapper jsonMapper = new ObjectMapper();
-            String json = jsonMapper.writeValueAsString(node);
+        ObjectMapper jsonMapper = new ObjectMapper();
+        String json = jsonMapper.writeValueAsString(node);
 
-            System.out.println(json);
-
-            assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":\"9\"}");
-        } catch(IOException e) {
-            e.printStackTrace();
-        }
+        assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":\"9\"}");
     }
 }

java-collections-conversions/README.md

@@ -0,0 +1,11 @@
+=========
+
+## Java Collections Cookbooks and Examples
+
+### Relevant Articles: 
+- [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)
+- [Converting a List to String in Java](http://www.baeldung.com/java-list-to-string)
+- [How to Convert List to Map in Java](http://www.baeldung.com/java-list-to-map)

java-collections-conversions/pom.xml

@@ -0,0 +1,40 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>java-collections-conversions</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <packaging>jar</packaging>
+    <name>java-collections-conversions</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-java</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-java</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-collections4</artifactId>
+            <version>${commons-collections4.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>${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>
+        <assertj.version>3.6.1</assertj.version>
+    </properties>
+</project>