merge

.gitignore

@@ -27,4 +27,5 @@ target/
 
 spring-openid/src/main/resources/application.properties
 .recommenders/
-/spring-hibernate4/nbproject/
+/spring-hibernate4/nbproject/
+spring-security-openid/src/main/resources/application.properties

apache-thrift/pom.xml

@@ -0,0 +1,68 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung</groupId>
+    <artifactId>apache-thrift</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <packaging>pom</packaging>
+
+    <properties>
+        <java.versin>1.8</java.versin>
+        <junit.version>4.12</junit.version>
+        <maven-compiler-plugin.version>3.6.0</maven-compiler-plugin.version>
+        <thrift.version>0.10.0</thrift.version>
+        <maven-thrift.version>0.1.11</maven-thrift.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.thrift</groupId>
+            <artifactId>libthrift</artifactId>
+            <version>${thrift.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-simple</artifactId>
+            <version>1.7.12</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <defaultGoal>install</defaultGoal>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>${maven-compiler-plugin.version}</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>build-helper-maven-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <phase>generate-sources</phase>
+                        <goals><goal>add-source</goal></goals>
+                        <configuration>
+                            <sources>
+                                <source>generated</source>
+                            </sources>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+</project>

apache-thrift/src/main/java/com/baeldung/thrift/Application.java

@@ -0,0 +1,11 @@
+package com.baeldung.thrift;
+
+import org.apache.thrift.transport.TTransportException;
+
+public class Application {
+
+    public static void main(String[] args) throws TTransportException {
+        CrossPlatformServiceServer server = new CrossPlatformServiceServer();
+        server.start();
+    }
+}

apache-thrift/src/main/java/com/baeldung/thrift/CrossPlatformServiceClient.java

@@ -0,0 +1,41 @@
+package com.baeldung.thrift;
+
+import com.baeldung.thrift.impl.CrossPlatformService;
+
+import org.apache.thrift.TException;
+import org.apache.thrift.protocol.TBinaryProtocol;
+import org.apache.thrift.protocol.TProtocol;
+import org.apache.thrift.transport.TSocket;
+import org.apache.thrift.transport.TTransport;
+import org.apache.thrift.transport.TTransportException;
+
+public class CrossPlatformServiceClient {
+
+    public boolean ping() {
+        try {
+            TTransport transport;
+
+            transport = new TSocket("localhost", 9090);
+            transport.open();
+
+            TProtocol protocol = new TBinaryProtocol(transport);
+            CrossPlatformService.Client client = new CrossPlatformService.Client(protocol);
+
+            System.out.print("Calling remote method...");
+
+            boolean result = client.ping();
+
+            System.out.println("done.");
+
+            transport.close();
+
+            return result;
+        } catch (TTransportException e) {
+            e.printStackTrace();
+        } catch (TException x) {
+            x.printStackTrace();
+        }
+
+        return false;
+    }
+}

apache-thrift/src/main/java/com/baeldung/thrift/CrossPlatformServiceImpl.java

@@ -0,0 +1,35 @@
+package com.baeldung.thrift;
+
+import com.baeldung.thrift.impl.CrossPlatformResource;
+import com.baeldung.thrift.impl.CrossPlatformService;
+import com.baeldung.thrift.impl.InvalidOperationException;
+
+import org.apache.thrift.TException;
+
+import java.util.Collections;
+import java.util.List;
+
+public class CrossPlatformServiceImpl implements CrossPlatformService.Iface {
+
+    @Override
+    public CrossPlatformResource get(final int id) throws InvalidOperationException, TException {
+        // add some action
+        return new CrossPlatformResource();
+    }
+
+    @Override
+    public void save(final CrossPlatformResource resource) throws InvalidOperationException, TException {
+        // add some action
+    }
+
+    @Override
+    public List<CrossPlatformResource> getList() throws InvalidOperationException, TException {
+        // add some action
+        return Collections.emptyList();
+    }
+
+    @Override
+    public boolean ping() throws InvalidOperationException, TException {
+        return true;
+    }
+}

apache-thrift/src/main/java/com/baeldung/thrift/CrossPlatformServiceServer.java

@@ -0,0 +1,36 @@
+package com.baeldung.thrift;
+
+import com.baeldung.thrift.impl.CrossPlatformService;
+
+import org.apache.thrift.server.TServer;
+import org.apache.thrift.server.TSimpleServer;
+import org.apache.thrift.transport.TServerSocket;
+import org.apache.thrift.transport.TServerTransport;
+import org.apache.thrift.transport.TTransportException;
+
+public class CrossPlatformServiceServer {
+
+    private TServer server;
+
+    public void start() throws TTransportException {
+        TServerTransport serverTransport = new TServerSocket(9090);
+        server = new TSimpleServer(new TServer.Args(serverTransport)
+            .processor(new CrossPlatformService.Processor<>(new CrossPlatformServiceImpl())));
+
+        System.out.print("Starting the server... ");
+
+        server.serve();
+
+        System.out.println("done.");
+    }
+
+    public void stop() {
+        if (server != null && server.isServing()) {
+            System.out.print("Stopping the server... ");
+
+            server.stop();
+
+            System.out.println("done.");
+        }
+    }
+}

apache-thrift/src/main/resources/cross-platform-service.thrift

@@ -0,0 +1,24 @@
+namespace cpp com.baeldung.thrift.impl
+namespace java com.baeldung.thrift.impl
+
+exception InvalidOperationException {
+    1: i32 code,
+    2: string description
+}
+
+struct CrossPlatformResource {
+    1: i32 id,
+    2: string name,
+    3: optional string salutation
+}
+
+service CrossPlatformService {
+
+    CrossPlatformResource get(1:i32 id) throws (1:InvalidOperationException e),
+
+    void save(1:CrossPlatformResource resource) throws (1:InvalidOperationException e),
+
+    list <CrossPlatformResource> getList() throws (1:InvalidOperationException e),
+
+    bool ping() throws (1:InvalidOperationException e)
+}

apache-thrift/src/test/java/com/baeldung/thrift/CrossPlatformServiceTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.thrift;
+
+import org.apache.thrift.transport.TTransportException;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class CrossPlatformServiceTest {
+
+    private CrossPlatformServiceServer server = new CrossPlatformServiceServer();
+
+    @Before
+    public void setUp() {
+        new Thread(() -> {
+            try {
+                server.start();
+            } catch (TTransportException e) {
+                e.printStackTrace();
+            }
+        }).start();
+        try {
+            // wait for the server start up
+            Thread.sleep(1000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @After
+    public void tearDown() {
+        server.stop();
+    }
+
+    @Test
+    public void ping() {
+        CrossPlatformServiceClient client = new CrossPlatformServiceClient();
+        Assert.assertTrue(client.ping());
+    }
+}

core-java-9/pom.xml

@@ -57,7 +57,6 @@
                 <configuration>
                     <source>1.9</source>
                     <target>1.9</target>
-                    <verbose>true</verbose>
                 </configuration>
             </plugin>
 
@@ -72,6 +71,9 @@
     </build>
 
     <properties>
+        <!-- project build encoding -->
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    
         <!-- logging -->
         <org.slf4j.version>1.7.21</org.slf4j.version>
 

core-java-9/src/test/java/com/baeldung/java9/language/collections/ListFactoryMethodsTest.java

@@ -0,0 +1,61 @@
+package com.baeldung.java9.language.collections;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+
+public class ListFactoryMethodsTest {
+
+    @Test
+    public void whenListCreated_thenSuccess() {
+        List<String> traditionlList = new ArrayList<String>();
+        traditionlList.add("foo");
+        traditionlList.add("bar");
+        traditionlList.add("baz");
+        List<String> factoryCreatedList = List.of("foo", "bar", "baz");
+        assertEquals(traditionlList, factoryCreatedList);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemAdd_ifUnSupportedOpExpnThrown_thenSuccess() {
+        List<String> list = List.of("foo", "bar");
+        list.add("baz");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemModify_ifUnSupportedOpExpnThrown_thenSuccess() {
+        List<String> list = List.of("foo", "bar");
+        list.set(0, "baz");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemRemove_ifUnSupportedOpExpnThrown_thenSuccess() {
+        List<String> list = List.of("foo", "bar");
+        list.remove("foo");
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void onNullElem_ifNullPtrExpnThrown_thenSuccess() {
+        List.of("foo", "bar", null);
+    }
+
+    @Test
+    public void ifNotArrayList_thenSuccess() {
+        List<String> list = List.of("foo", "bar");
+        assertFalse(list instanceof ArrayList);
+    }
+
+    @Test
+    public void ifListSizeIsOne_thenSuccess() {
+        int[] arr = { 1, 2, 3, 4 };
+        List<int[]> list = List.of(arr);
+        assertEquals(1, list.size());
+        assertArrayEquals(arr, list.get(0));
+    }
+
+}

core-java-9/src/test/java/com/baeldung/java9/language/collections/MapFactoryMethodsTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.java9.language.collections;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+
+public class MapFactoryMethodsTest {
+
+    @Test
+    public void whenMapCreated_thenSuccess() {
+        Map<String, String> traditionlMap = new HashMap<String, String>();
+        traditionlMap.put("foo", "a");
+        traditionlMap.put("bar", "b");
+        traditionlMap.put("baz", "c");
+        Map<String, String> factoryCreatedMap = Map.of("foo", "a", "bar", "b", "baz", "c");
+        assertEquals(traditionlMap, factoryCreatedMap);
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemAdd_ifUnSupportedOpExpnThrown_thenSuccess() {
+        Map<String, String> map = Map.of("foo", "a", "bar", "b");
+        map.put("baz", "c");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemModify_ifUnSupportedOpExpnThrown_thenSuccess() {
+        Map<String, String> map = Map.of("foo", "a", "bar", "b");
+        map.put("foo", "c");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemRemove_ifUnSupportedOpExpnThrown_thenSuccess() {
+        Map<String, String> map = Map.of("foo", "a", "bar", "b");
+        map.remove("foo");
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void givenDuplicateKeys_ifIllegalArgExp_thenSuccess() {
+        Map.of("foo", "a", "foo", "b");
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void onNullKey_ifNullPtrExp_thenSuccess() {
+        Map.of("foo", "a", null, "b");
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void onNullValue_ifNullPtrExp_thenSuccess() {
+        Map.of("foo", "a", "bar", null);
+    }
+
+    @Test
+    public void ifNotHashMap_thenSuccess() {
+        Map<String, String> map = Map.of("foo", "a", "bar", "b");
+        assertFalse(map instanceof HashMap);
+    }
+
+}

core-java-9/src/test/java/com/baeldung/java9/language/collections/SetFactoryMethodsTest.java

@@ -0,0 +1,60 @@
+package com.baeldung.java9.language.collections;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+
+public class SetFactoryMethodsTest {
+
+    @Test
+    public void whenSetCreated_thenSuccess() {
+        Set<String> traditionlSet = new HashSet<String>();
+        traditionlSet.add("foo");
+        traditionlSet.add("bar");
+        traditionlSet.add("baz");
+        Set<String> factoryCreatedSet = Set.of("foo", "bar", "baz");
+        assertEquals(traditionlSet, factoryCreatedSet);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void onDuplicateElem_IfIllegalArgExp_thenSuccess() {
+        Set.of("foo", "bar", "baz", "foo");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemAdd_ifUnSupportedOpExpnThrown_thenSuccess() {
+        Set<String> set = Set.of("foo", "bar");
+        set.add("baz");
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void onElemRemove_ifUnSupportedOpExpnThrown_thenSuccess() {
+        Set<String> set = Set.of("foo", "bar", "baz");
+        set.remove("foo");
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void onNullElem_ifNullPtrExpnThrown_thenSuccess() {
+        Set.of("foo", "bar", null);
+    }
+
+    @Test
+    public void ifNotHashSet_thenSuccess() {
+        Set<String> list = Set.of("foo", "bar");
+        assertFalse(list instanceof HashSet);
+    }
+
+    @Test
+    public void ifSetSizeIsOne_thenSuccess() {
+        int[] arr = { 1, 2, 3, 4 };
+        Set<int[]> set = Set.of(arr);
+        assertEquals(1, set.size());
+        assertArrayEquals(arr, set.iterator().next());
+    }
+
+}

core-java/README.md

@@ -54,3 +54,6 @@
 - [The Basics of Java Generics](http://www.baeldung.com/java-generics)
 - [The Traveling Salesman Problem in Java](http://www.baeldung.com/java-simulated-annealing-for-traveling-salesman)
 - [How to Create an Executable JAR with Maven](http://www.baeldung.com/executable-jar-with-maven)
+- [Guide to java.util.concurrent.Future](http://www.baeldung.com/java-future)
+- [Guide to java.util.concurrent.BlockingQueue](http://www.baeldung.com/java-blocking-queue)
+- [Guide to CountDownLatch in Java](http://www.baeldung.com/java-countdown-latch)

core-java/src/test/java/com/baeldung/CharArrayToStringUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+public class CharArrayToStringUnitTest {
+
+    @Test
+    public void givenCharArray_whenCallingStringConstructor_shouldConvertToString() {
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = new String(charArray);
+        String expectedValue = "character";
+        
+        assertEquals(expectedValue, result);
+    }
+    
+    @Test
+    public void givenCharArray_whenCallingStringConstructorWithOffsetAndLength_shouldConvertToString(){
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = new String(charArray, 4, 3);
+        String expectedValue = "act";
+        
+        assertEquals(expectedValue, result);
+    }
+    
+    @Test
+    public void givenCharArray_whenCallingStringCopyValueOf_shouldConvertToString(){
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = String.copyValueOf(charArray);
+        String expectedValue = "character";
+        
+        assertEquals(expectedValue, result);
+    }
+    
+    @Test
+    public void givenCharArray_whenCallingStringCopyValueOfWithOffsetAndLength_shouldConvertToString(){
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = String.copyValueOf(charArray, 0, 4);
+        String expectedValue = "char";
+        
+        assertEquals(expectedValue, result);
+    }
+    
+    @Test
+    public void givenCharArray_whenCallingStringValueOf_shouldConvertToString(){
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = String.valueOf(charArray);
+        String expectedValue = "character";
+        
+        assertEquals(expectedValue, result);
+    }
+    
+    @Test
+    public void givenCharArray_whenCallingStringValueOfWithOffsetAndLength_shouldConvertToString(){
+        char[] charArray = {'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r'};
+        String result = String.valueOf(charArray, 3, 4);
+        String expectedValue = "ract";
+        
+        assertEquals(expectedValue, result);
+    }
+}

core-java/src/test/java/com/baeldung/StringToCharArrayUnitTest.java

@@ -0,0 +1,20 @@
+package com.baeldung;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+public class StringToCharArrayUnitTest {
+
+@Test
+public void givenString_whenCallingStringToCharArray_shouldConvertToCharArray() {
+    String givenString = "characters";
+
+    char[] result = givenString.toCharArray();
+
+    char[] expectedCharArray = { 'c', 'h', 'a', 'r', 'a', 'c', 't', 'e', 'r', 's' };
+
+    assertArrayEquals(expectedCharArray, result);
+}
+
+}

core-java/src/test/java/com/baeldung/concurrent/priorityblockingqueue/PriorityBlockingQueueUnitTest.java

@@ -0,0 +1,51 @@
+package com.baeldung.concurrent.priorityblockingqueue;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.concurrent.PriorityBlockingQueue;
+import java.util.concurrent.TimeUnit;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.util.Lists.newArrayList;
+
+public class PriorityBlockingQueueUnitTest {
+
+    @Test
+    public void givenUnorderedValues_whenPolling_thenShouldOrderQueue() throws InterruptedException {
+        PriorityBlockingQueue<Integer> queue = new PriorityBlockingQueue<>();
+        ArrayList<Integer> polledElements = new ArrayList<>();
+
+        queue.add(1);
+        queue.add(5);
+        queue.add(2);
+        queue.add(3);
+        queue.add(4);
+
+        queue.drainTo(polledElements);
+
+        assertThat(polledElements).containsExactly(1, 2, 3, 4, 5);
+    }
+
+    @Test
+    public void whenPollingEmptyQueue_thenShouldBlockThread() throws InterruptedException {
+        PriorityBlockingQueue<Integer> queue = new PriorityBlockingQueue<>();
+
+        final Thread thread = new Thread(() -> {
+          System.out.println("Polling...");
+          while (true) {
+            try {
+              Integer poll = queue.take();
+              System.out.println("Polled: " + poll);
+            } catch (InterruptedException e) {}
+          }
+        });
+        thread.start();
+
+        Thread.sleep(TimeUnit.SECONDS.toMillis(5));
+        System.out.println("Adding to queue");
+
+        queue.addAll(newArrayList(1, 5, 6, 1, 2, 6, 7));
+        Thread.sleep(TimeUnit.SECONDS.toMillis(1));
+    }
+}

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

@@ -0,0 +1,41 @@
+package org.baeldung.java.streams;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ForkJoinPool;
+import java.util.stream.Collectors;
+import java.util.stream.LongStream;
+import java.util.stream.Stream;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class ThreadPoolInParallelStreamTest {
+    
+    @Test
+    public void giveRangeOfLongs_whenSummedInParallel_shouldBeEqualToExpectedTotal() 
+      throws InterruptedException, ExecutionException {
+        long firstNum = 1;
+        long lastNum = 1_000_000;
+
+        List<Long> aList = LongStream.rangeClosed(firstNum, lastNum).boxed()
+          .collect(Collectors.toList());
+
+        ForkJoinPool customThreadPool = new ForkJoinPool(4);
+        long actualTotal = customThreadPool.submit(() -> aList.parallelStream()
+          .reduce(0L, Long::sum)).get();
+        
+        assertEquals((lastNum + firstNum) * lastNum / 2, actualTotal);
+    }
+    
+    @Test
+    public void givenList_whenCallingParallelStream_shouldBeParallelStream(){
+        List<Long> aList = new ArrayList<>();
+        Stream<Long> parallelStream = aList.parallelStream();
+        
+        assertTrue(parallelStream.isParallel());
+    }
+}

guava/src/test/java/org/baeldung/guava/CustomEvent.java

@@ -0,0 +1,18 @@
+package org.baeldung.guava;
+
+
+public class CustomEvent {
+    private String action;
+
+    public CustomEvent(String action) {
+        this.action = action;
+    }
+
+    public String getAction() {
+        return action;
+    }
+
+    public void setAction(String action) {
+        this.action = action;
+    }
+}

guava/src/test/java/org/baeldung/guava/EventBusWrapper.java

@@ -0,0 +1,22 @@
+package org.baeldung.guava;
+
+import com.google.common.eventbus.EventBus;
+
+class EventBusWrapper {
+
+    private static EventBus eventBus = new EventBus();
+
+    static void register(Object object){
+        eventBus.register(object);
+    }
+
+    static void unregister(Object object){
+        eventBus.unregister(object);
+    }
+
+    static void post(Object object){
+        eventBus.post(object);
+    }
+
+
+}

guava/src/test/java/org/baeldung/guava/EventListener.java

@@ -0,0 +1,33 @@
+package org.baeldung.guava;
+import com.google.common.eventbus.Subscribe;
+
+public class EventListener {
+
+    private static int eventsHandled;
+
+    /**
+     * Handles events of type String     *
+     */
+    @Subscribe
+    public void stringEvent(String event){
+        System.out.println("do event ["+event+"]");
+        eventsHandled++;
+    }
+
+    /**
+     * Handles events of type CustomEvent
+     */
+    @Subscribe
+    public void someEvent(CustomEvent customEvent){
+        System.out.println("do event ["+ customEvent.getAction()+"]");
+        eventsHandled++;
+    }
+
+    public int getEventsHandled() {
+        return eventsHandled;
+    }
+
+    public void resetEventsHandled(){
+        eventsHandled = 0;
+    }
+}

guava/src/test/java/org/baeldung/guava/GuavaEventBusTest.java

@@ -0,0 +1,42 @@
+package org.baeldung.guava;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class GuavaEventBusTest {
+
+    private EventListener listener;
+
+    @Before
+    public void setUp() throws Exception {
+        listener = new EventListener();
+        EventBusWrapper.register(listener);
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        EventBusWrapper.unregister(listener);
+    }
+
+    @Test
+    public void givenStringEvent_whenEventHandled_thenSuccess() throws Exception {
+        listener.resetEventsHandled();
+
+        EventBusWrapper.post("String Event");
+        assertEquals(1, listener.getEventsHandled());
+
+    }
+
+    @Test
+    public void givenCustomEvent_whenEventHandled_thenSuccess() throws Exception {
+        listener.resetEventsHandled();
+
+        CustomEvent customEvent = new CustomEvent("Custom Event");
+        EventBusWrapper.post(customEvent);
+
+        assertEquals(1, listener.getEventsHandled());
+    }
+}

guava/src/test/java/org/baeldung/guava/GuavaOrderingTest.java

@@ -0,0 +1,91 @@
+package org.baeldung.guava;
+
+import com.google.common.base.Function;
+import com.google.common.collect.Ordering;
+import com.google.common.primitives.Ints;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+
+public class GuavaOrderingTest {
+    @Test
+    public void givenListOfIntegers_whenCreateNaturalOrderOrdering_shouldSortProperly() {
+        //given
+        List<Integer> integers = Arrays.asList(3, 2, 1);
+
+        //when
+        integers.sort(Ordering.natural());
+
+        //then
+        assertEquals(Arrays.asList(1, 2, 3), integers);
+    }
+
+    @Test
+    public void givenListOfPersonObject_whenSortedUsingCustomOrdering_shouldSortProperly() {
+        //given
+        List<Person> persons = Arrays.asList(new Person("Michael", 10), new Person("Alice", 3));
+        Ordering<Person> orderingByAge = new Ordering<Person>() {
+            @Override
+            public int compare(Person p1, Person p2) {
+                return Ints.compare(p1.age, p2.age);
+            }
+        };
+
+        //when
+        persons.sort(orderingByAge);
+
+        //then
+        assertEquals(Arrays.asList(new Person("Alice", 3), new Person("Michael", 10)), persons);
+    }
+
+    @Test
+    public void givenListOfPersonObject_whenSortedUsingChainedOrdering_shouldSortPropely() {
+        //given
+        List<Person> persons = Arrays.asList(new Person("Michael", 10), new Person("Alice", 3), new Person("Thomas", null));
+        Ordering<Person> ordering = Ordering.natural().nullsFirst().onResultOf(new Function<Person, Comparable>() {
+            @Override
+            public Comparable apply(Person person) {
+                return person.age;
+            }
+        });
+
+        //when
+        persons.sort(ordering);
+
+        //then
+        assertEquals(Arrays.asList(new Person("Thomas", null), new Person("Alice", 3), new Person("Michael", 10)), persons);
+    }
+
+
+    class Person {
+        private final String name;
+        private final Integer age;
+
+        private Person(String name, Integer age) {
+            this.name = name;
+            this.age = age;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+
+            Person person = (Person) o;
+
+            if (name != null ? !name.equals(person.name) : person.name != null) return false;
+            return age != null ? age.equals(person.age) : person.age == null;
+
+        }
+
+        @Override
+        public int hashCode() {
+            int result = name != null ? name.hashCode() : 0;
+            result = 31 * result + (age != null ? age.hashCode() : 0);
+            return result;
+        }
+    }
+}

javaslang/src/main/java/com/baeldung/javaslang/exception/handling/JavaTryCatch.java

@@ -0,0 +1,21 @@
+package com.baeldung.javaslang.exception.handling;
+
+import com.baeldung.javaslang.exception.handling.client.ClientException;
+import com.baeldung.javaslang.exception.handling.client.HttpClient;
+import com.baeldung.javaslang.exception.handling.client.Response;
+
+public class JavaTryCatch {
+    private HttpClient httpClient;
+
+    public JavaTryCatch(HttpClient httpClient) {
+        this.httpClient = httpClient;
+    }
+
+    public Response getResponse() {
+        try {
+            return httpClient.call();
+        } catch (ClientException e) {
+            return null;
+        }
+    }
+}

javaslang/src/main/java/com/baeldung/javaslang/exception/handling/JavaslangTry.java

@@ -0,0 +1,18 @@
+package com.baeldung.javaslang.exception.handling;
+
+
+import com.baeldung.javaslang.exception.handling.client.HttpClient;
+import com.baeldung.javaslang.exception.handling.client.Response;
+import javaslang.control.Try;
+
+public class JavaslangTry {
+    private final HttpClient httpClient;
+
+    public JavaslangTry(HttpClient httpClient) {
+        this.httpClient = httpClient;
+    }
+
+    public Try<Response> getResponse() {
+        return Try.of(httpClient::call);
+    }
+}

javaslang/src/main/java/com/baeldung/javaslang/exception/handling/client/ClientException.java

@@ -0,0 +1,8 @@
+package com.baeldung.javaslang.exception.handling.client;
+
+
+public class ClientException extends Exception {
+    public ClientException(String message) {
+        super(message);
+    }
+}

javaslang/src/main/java/com/baeldung/javaslang/exception/handling/client/HttpClient.java

@@ -0,0 +1,6 @@
+package com.baeldung.javaslang.exception.handling.client;
+
+
+public interface HttpClient {
+    Response call() throws ClientException;
+}

javaslang/src/main/java/com/baeldung/javaslang/exception/handling/client/Response.java

@@ -0,0 +1,9 @@
+package com.baeldung.javaslang.exception.handling.client;
+
+public class Response {
+    public final String id;
+
+    public Response(String id) {
+        this.id = id;
+    }
+}