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

aws/src/main/java/com/baeldung/s3/S3Application.java

@@ -1,9 +1,10 @@
 package com.baeldung.s3;
 
 import java.io.File;
-import java.io.FileOutputStream;
 import java.io.IOException;
 
+import org.apache.commons.io.FileUtils;
+
 import com.amazonaws.auth.AWSCredentials;
 import com.amazonaws.auth.AWSStaticCredentialsProvider;
 import com.amazonaws.auth.BasicAWSCredentials;
@@ -28,7 +29,7 @@ public class S3Application {
           "<AWS accesskey>", 
           "<AWS secretkey>"
         );
-    }  
+    }
     
     public static void main(String[] args) throws IOException {
         //set-up the client
@@ -74,15 +75,7 @@ public class S3Application {
         //downloading an object
         S3Object s3object = awsService.getObject(bucketName, "Document/hello.txt");
         S3ObjectInputStream inputStream = s3object.getObjectContent();
-        FileOutputStream fos = new FileOutputStream(new File("/Users/user/Desktop/hello.txt"));
-
-        int read = 0;
-        byte[] bytes = new byte[1024];
-        while ((read = inputStream.read(bytes)) != -1) {
-            fos.write(bytes, 0, read);
-        }
-        inputStream.close();
-        fos.close();
+        FileUtils.copyInputStreamToFile(inputStream, new File("/Users/user/Desktop/hello.txt"));
         
         //copying an object
         awsService.copyObject(

camel-api/src/main/java/com/baeldung/camel/Application.java

@@ -13,14 +13,13 @@ import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.web.servlet.ServletRegistrationBean;
-import org.springframework.boot.web.support.SpringBootServletInitializer;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.stereotype.Component;
 
 @SpringBootApplication
 @ComponentScan(basePackages="com.baeldung.camel")
-public class Application extends SpringBootServletInitializer {
+public class Application{
 
     @Value("${server.port}")
     String serverPort;
@@ -62,10 +61,12 @@ public class Application extends SpringBootServletInitializer {
                 .bindingMode(RestBindingMode.json)
                 .dataFormatProperty("prettyPrint", "true");
 /** 
-The Rest DSL supports automatic binding json/xml contents to/from POJOs using Camels Data Format.
-By default the binding mode is off, meaning there is no automatic binding happening for incoming and outgoing messages.
-You may want to use binding if you develop POJOs that maps to your REST services request and response types. 
-This allows you, as a developer, to work with the POJOs in Java code.
+The Rest DSL supports automatic binding json/xml contents to/from 
+POJOs using Camels Data Format.
+By default the binding mode is off, meaning there is no automatic 
+binding happening for incoming and outgoing messages.
+You may want to use binding if you develop POJOs that maps to 
+your REST services request and response types. 
 */         
             
             rest("/api/").description("Teste REST Service")

core-java/hashcode/pom.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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.hashcode</groupId>
+    <artifactId>hashcode</artifactId>
+    <version>1.0</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+            <version>1.7.25</version>
+        </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-simple</artifactId>
+            <version>1.7.25</version>
+        </dependency>
+    </dependencies>
+</project>

core-java/hashcode/src/main/java/com/baeldung/application/Application.java

@@ -0,0 +1,23 @@
+package com.baeldung.application;
+
+import com.baeldung.entities.User;
+import java.util.HashMap;
+import java.util.Map;
+
+public class Application {
+
+    public static void main(String[] args) {
+        Map<User, User> users = new HashMap<>();
+        User user1 = new User(1L, "John", "[email protected]");
+        User user2 = new User(2L, "Jennifer", "[email protected]");
+        User user3 = new User(3L, "Mary", "[email protected]");
+
+        users.put(user1, user1);
+        users.put(user2, user2);
+        users.put(user3, user3);
+
+        if (users.containsKey(user1)) {
+            System.out.print("User found in the collection");
+        }
+    }
+}

core-java/hashcode/src/main/java/com/baeldung/entities/User.java

@@ -0,0 +1,38 @@
+package com.baeldung.entities;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class User {
+
+    private final Logger logger = LoggerFactory.getLogger(User.class);
+    private long id;
+    private String name;
+    private String email;
+
+    public User(long id, String name, String email) {
+        this.id = id;
+        this.name = name;
+        this.email = email;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null) return false;
+        if (this.getClass() != o.getClass()) return false;
+        User user = (User) o;
+        return id != user.id && (!name.equals(user.name) && !email.equals(user.email));
+    }
+    	
+    @Override
+    public int hashCode() {
+        int hash = 7;
+        hash = 31 * hash + (int) id;
+        hash = 31 * hash + (name == null ? 0 : name.hashCode());
+        hash = 31 * hash + (email == null ? 0 : email.hashCode());
+        logger.info("hashCode() method called - Computed hash: " + hash);
+        return hash;
+    }
+    // getters and setters here
+}

core-java/hashcode/src/test/java/com/baeldung/application/ApplicationTest.java

@@ -0,0 +1,30 @@
+package com.baeldung.application;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import static org.junit.Assert.assertEquals;
+
+public class ApplicationTest {
+
+    private ByteArrayOutputStream outContent;
+
+    @Before
+    public void setUpPrintStreamInstance() throws Exception {
+        this.outContent = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(outContent));
+    }
+
+    @After
+    public void tearDownByteArrayOutputStream() throws Exception {
+        outContent = null;
+    }
+
+    @Test
+    public void main_NoInputState_TextPrintedToConsole() throws Exception {
+        Application.main(new String[]{});
+        assertEquals("User found in the collection", outContent.toString());
+    }
+}

core-java/hashcode/src/test/java/com/baeldung/entities/UserTest.java

@@ -0,0 +1,34 @@
+package com.baeldung.entities;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class UserTest {
+
+    private User user;
+    private User comparisonUser;
+
+    @Before
+    public void setUpUserInstances() {
+        this.user = new User(1L, "test", "[email protected]");
+        this.comparisonUser = this.user;
+    }
+
+    @After
+    public void tearDownUserInstances() {
+        user = null;
+        comparisonUser = null;
+    }
+
+    @Test
+    public void equals_EqualUserInstance_TrueAssertion(){
+        Assert.assertTrue(user.equals(comparisonUser));
+    }
+
+    @Test
+    public void hashCode_UserHash_TrueAssertion() {
+        Assert.assertEquals(1792276941, user.hashCode());
+    }
+}

core-java/src/main/java/com/baeldung/concurrent/Scheduledexecutorservice/ScheduledExecutorServiceDemo.java

@@ -0,0 +1,34 @@
+package com.baeldung.concurrent.Scheduledexecutorservice;
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+public class ScheduledExecutorServiceDemo {
+
+	public void execute() {
+		ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
+
+		ScheduledFuture<?> scheduledFuture = executorService.schedule(() -> {
+			// Task
+		}, 1, TimeUnit.SECONDS);
+
+		executorService.scheduleAtFixedRate(() -> {
+			// Task
+		}, 1, 10, TimeUnit.SECONDS);
+
+		executorService.scheduleWithFixedDelay(() -> {
+			// Task
+		}, 1, 10, TimeUnit.SECONDS);
+
+		Future<String> future = executorService.schedule(() -> {
+			// Task
+			return "Hellow world";
+		}, 1, TimeUnit.SECONDS);
+
+		executorService.shutdown();
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/atomic/SafeCounterWithLock.java

@@ -0,0 +1,13 @@
+package com.baeldung.concurrent.atomic;
+
+public class SafeCounterWithLock {
+    private volatile int counter;
+    
+    public int getValue() {
+        return counter;
+    }
+    
+    public synchronized void increment() {
+        counter++;
+    }
+}

core-java/src/main/java/com/baeldung/concurrent/atomic/SafeCounterWithoutLock.java

@@ -0,0 +1,21 @@
+package com.baeldung.concurrent.atomic;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class SafeCounterWithoutLock {
+    private final AtomicInteger counter = new AtomicInteger(0);
+    
+    public int getValue() {
+        return counter.get();
+    }
+    
+    public void increment() {
+        while(true) {
+            int existingValue = getValue();
+            int newValue = existingValue + 1;
+            if(counter.compareAndSet(existingValue, newValue)) {
+                return;
+            }
+        }
+    }
+}

core-java/src/main/java/com/baeldung/concurrent/atomic/UnsafeCounter.java

@@ -0,0 +1,13 @@
+package com.baeldung.concurrent.atomic;
+
+public class UnsafeCounter {
+    int counter;
+    
+    public int getValue() {
+        return counter;
+    }
+    
+    public void increment() {
+        counter++;
+    }
+}

core-java/src/main/java/com/baeldung/concurrent/cyclicbarrier/CyclicBarrierExample.java

@@ -0,0 +1,25 @@
+package com.baeldung.concurrent.cyclicbarrier;
+
+import java.util.concurrent.CyclicBarrier;
+
+public class CyclicBarrierExample {
+
+	public void start() {
+		CyclicBarrier cyclicBarrier = new CyclicBarrier(3, () -> {
+			// Task
+			System.out.println("All previous tasks are completed");
+		});
+
+		Thread t1 = new Thread(new Task(cyclicBarrier), "T1");
+		Thread t2 = new Thread(new Task(cyclicBarrier), "T2");
+		Thread t3 = new Thread(new Task(cyclicBarrier), "T3");
+
+		if (!cyclicBarrier.isBroken()) {
+			t1.start();
+			t2.start();
+			t3.start();
+		}
+
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/cyclicbarrier/Task.java

@@ -0,0 +1,25 @@
+package com.baeldung.concurrent.cyclicbarrier;
+
+import java.util.concurrent.BrokenBarrierException;
+import java.util.concurrent.CyclicBarrier;
+
+public class Task implements Runnable {
+
+    private CyclicBarrier barrier;
+    
+	public Task(CyclicBarrier barrier) {
+		this.barrier = barrier;
+	}
+
+	@Override
+	public void run() {
+        try {
+        	System.out.println("Thread : "+ Thread.currentThread().getName() + " is waiting");
+			barrier.await();
+			System.out.println("Thread : "+ Thread.currentThread().getName() + " is released");
+		} catch (InterruptedException | BrokenBarrierException e) {
+			e.printStackTrace();
+		}
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/executor/ExecutorDemo.java

@@ -0,0 +1,14 @@
+package com.baeldung.concurrent.executor;
+
+import java.util.concurrent.Executor;
+
+public class ExecutorDemo {
+
+	public void execute() {
+		Executor executor = new Invoker();
+		executor.execute(()->{
+			// task to be performed
+		});
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/executor/Invoker.java

@@ -0,0 +1,12 @@
+package com.baeldung.concurrent.executor;
+
+import java.util.concurrent.Executor;
+
+public class Invoker implements Executor {
+
+	@Override
+	public void execute(Runnable r) {
+		r.run();
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/executorservice/ExecutorServiceDemo.java

@@ -0,0 +1,27 @@
+package com.baeldung.concurrent.executorservice;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+
+public class ExecutorServiceDemo {
+
+	ExecutorService executor = Executors.newFixedThreadPool(10);
+
+	public void execute() {
+
+		executor.submit(() -> {
+			new Task();
+		});
+
+		executor.shutdown();
+		executor.shutdownNow();
+		try {
+			executor.awaitTermination(20l, TimeUnit.NANOSECONDS);
+		} catch (InterruptedException e) {
+			e.printStackTrace();
+		}
+
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/executorservice/Task.java

@@ -0,0 +1,10 @@
+package com.baeldung.concurrent.executorservice;
+
+public class Task implements Runnable {
+
+	@Override
+	public void run() {
+		// task details
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/future/FutureDemo.java

@@ -0,0 +1,44 @@
+package com.baeldung.concurrent.future;
+
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+public class FutureDemo {
+
+	public String invoke() {
+
+		String str = null;
+
+		ExecutorService executorService = Executors.newFixedThreadPool(10);
+
+		Future<String> future = executorService.submit(() -> {
+			// Task
+			Thread.sleep(10000l);
+			return "Hellow world";
+		});
+
+		future.cancel(false);
+
+		try {
+			future.get(20, TimeUnit.SECONDS);
+		} catch (InterruptedException | ExecutionException | TimeoutException e1) {
+			e1.printStackTrace();
+		}
+
+		if (future.isDone() && !future.isCancelled()) {
+			try {
+				str = future.get();
+			} catch (InterruptedException | ExecutionException e) {
+				e.printStackTrace();
+			}
+		}
+
+		return str;
+
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/semaphore/SemaPhoreDemo.java

@@ -0,0 +1,22 @@
+package com.baeldung.concurrent.semaphore;
+
+import java.util.concurrent.Semaphore;
+
+public class SemaPhoreDemo {
+
+	static Semaphore semaphore = new Semaphore(10);
+	
+	public void execute() throws InterruptedException {
+
+		System.out.println("Available permit : " + semaphore.availablePermits());
+		System.out.println("Number of threads waiting to acquire: " + semaphore.getQueueLength());
+
+		if (semaphore.tryAcquire()) {
+			semaphore.acquire();
+			// perform some critical operations
+			semaphore.release();
+		}
+
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/threadfactory/BaeldungThreadFactory.java

@@ -0,0 +1,23 @@
+package com.baeldung.concurrent.threadfactory;
+
+import java.util.concurrent.ThreadFactory;
+
+public class BaeldungThreadFactory implements ThreadFactory {
+
+	private int threadId;
+	private String name;
+
+	public BaeldungThreadFactory(String name) {
+		threadId = 1;
+		this.name = name;
+	}
+
+	@Override
+	public Thread newThread(Runnable r) {
+		Thread t = new Thread(r, name + "-Thread_" + threadId);
+		System.out.println("created new thread with id : " + threadId + " and name : " + t.getName());
+		threadId++;
+		return t;
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/threadfactory/Demo.java

@@ -0,0 +1,13 @@
+package com.baeldung.concurrent.threadfactory;
+
+public class Demo {
+
+	public void execute() {
+		BaeldungThreadFactory factory = new BaeldungThreadFactory("BaeldungThreadFactory");
+		for (int i = 0; i < 10; i++) {
+			Thread t = factory.newThread(new Task());
+			t.start();
+		}
+	}
+
+}

core-java/src/main/java/com/baeldung/concurrent/threadfactory/Task.java

@@ -0,0 +1,10 @@
+package com.baeldung.concurrent.threadfactory;
+
+public class Task implements Runnable {
+
+	@Override
+	public void run() {
+		// task details
+	}
+	
+}

core-java/src/main/java/com/baeldung/deserialization/AppleProduct.java

@@ -4,12 +4,12 @@ import java.io.Serializable;
 
 public class AppleProduct implements Serializable {
 
-     private static final long serialVersionUID = 1234567L; // user-defined (i.e. not default or generated)
-//    private static final long serialVersionUID = 7654321L; // user-defined (i.e. not default or generated)
+    private static final long serialVersionUID = 1234567L; // user-defined (i.e. not default or generated)
+    // private static final long serialVersionUID = 7654321L; // user-defined (i.e. not default or generated)
 
     public String headphonePort;
     public String thunderboltPort;
-    public String lighteningPort;
+    public String lightningPort;
 
     public String getHeadphonePort() {
         return headphonePort;
@@ -23,4 +23,8 @@ public class AppleProduct implements Serializable {
         return serialVersionUID;
     }
 
+    public String getLightningPort() {
+        return lightningPort;
+    }
+
 }

core-java/src/main/java/com/baeldung/deserialization/DeserializationUtility.java

@@ -9,11 +9,12 @@ public class DeserializationUtility {
 
     public static void main(String[] args) throws ClassNotFoundException, IOException {
 
-        String serializedObj = "rO0ABXNyACljb20uYmFlbGR1bmcuZGVzZXJpYWxpemF0aW9uLkFwcGxlUHJvZHVjdAAAAAAAEtaHAgADTAANaGVhZHBob25lUG9ydHQAEkxqYXZhL2xhbmcvU3RyaW5nO0wADmxpZ2h0ZW5pbmdQb3J0cQB+AAFMAA90aHVuZGVyYm9sdFBvcnRxAH4AAXhwdAARaGVhZHBob25lUG9ydDIwMjBwdAATdGh1bmRlcmJvbHRQb3J0MjAyMA==";
+        String serializedObj = "rO0ABXNyACljb20uYmFlbGR1bmcuZGVzZXJpYWxpemF0aW9uLkFwcGxlUHJvZHVjdAAAAAAAEtaHAgADTAANaGVhZHBob25lUG9ydHQAEkxqYXZhL2xhbmcvU3RyaW5nO0wADWxpZ2h0bmluZ1BvcnRxAH4AAUwAD3RodW5kZXJib2x0UG9ydHEAfgABeHB0ABFoZWFkcGhvbmVQb3J0MjAyMHQAEWxpZ2h0bmluZ1BvcnQyMDIwdAATdGh1bmRlcmJvbHRQb3J0MjAyMA==";
         System.out.println("Deserializing AppleProduct...");
         AppleProduct deserializedObj = (AppleProduct) deSerializeObjectFromString(serializedObj);
         System.out.println("Headphone port of AppleProduct:" + deserializedObj.getHeadphonePort());
         System.out.println("Thunderbolt port of AppleProduct:" + deserializedObj.getThunderboltPort());
+        System.out.println("LightningPort port of AppleProduct:" + deserializedObj.getLightningPort());
     }
 
     public static Object deSerializeObjectFromString(String s) throws IOException, ClassNotFoundException {

core-java/src/main/java/com/baeldung/deserialization/SerializationUtility.java

@@ -13,6 +13,7 @@ public class SerializationUtility {
         AppleProduct macBook = new AppleProduct();
         macBook.headphonePort = "headphonePort2020";
         macBook.thunderboltPort = "thunderboltPort2020";
+        macBook.lightningPort = "lightningPort2020";
 
         String serializedObj = serializeObjectToString(macBook);
         System.out.println("Serialized AppleProduct object to string:");

core-java/src/main/java/com/baeldung/temporaladjuster/CustomTemporalAdjuster.java

@@ -10,14 +10,13 @@ public class CustomTemporalAdjuster implements TemporalAdjuster {
 
     @Override
     public Temporal adjustInto(Temporal temporal) {
-        DayOfWeek dayOfWeek = DayOfWeek.of(temporal.get(ChronoField.DAY_OF_WEEK));
-        int daysToAdd;
-        if (dayOfWeek == DayOfWeek.FRIDAY)
-            daysToAdd = 3;
-        else if (dayOfWeek == DayOfWeek.SATURDAY)
-            daysToAdd = 2;
-        else
-            daysToAdd = 1;
-        return temporal.plus(daysToAdd, ChronoUnit.DAYS);
+        switch (DayOfWeek.of(temporal.get(ChronoField.DAY_OF_WEEK))) {
+            case FRIDAY:
+                return temporal.plus(3, ChronoUnit.DAYS);
+            case SATURDAY:
+                return temporal.plus(2, ChronoUnit.DAYS);
+            default:
+                return temporal.plus(1, ChronoUnit.DAYS);
+        }
     }
 }

core-java/src/test/java/com/baeldung/concurrent/atomic/ThreadSafeCounterTest.java

@@ -0,0 +1,38 @@
+package com.baeldung.concurrent.atomic;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+import org.junit.Test;
+
+public class ThreadSafeCounterTest {
+
+    @Test
+    public void givenMultiThread_whenSafeCounterWithLockIncrement() throws InterruptedException {
+        ExecutorService service = Executors.newFixedThreadPool(3);
+        SafeCounterWithLock safeCounter = new SafeCounterWithLock();
+
+        IntStream.range(0, 1000)
+          .forEach(count -> service.submit(safeCounter::increment));
+        service.awaitTermination(100, TimeUnit.MILLISECONDS);
+
+        assertEquals(1000, safeCounter.getValue());
+    }
+    
+    @Test
+    public void givenMultiThread_whenSafeCounterWithoutLockIncrement() throws InterruptedException {
+        ExecutorService service = Executors.newFixedThreadPool(3);
+        SafeCounterWithoutLock safeCounter = new SafeCounterWithoutLock();
+
+        IntStream.range(0, 1000)
+          .forEach(count -> service.submit(safeCounter::increment));
+        service.awaitTermination(100, TimeUnit.MILLISECONDS);
+
+        assertEquals(1000, safeCounter.getValue());
+    }
+    
+}

core-java/src/test/java/com/baeldung/concurrent/atomic/ThreadUnsafeCounterManualTest.java

@@ -0,0 +1,33 @@
+package com.baeldung.concurrent.atomic;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+import org.junit.Test;
+
+/**
+ * This test shows the behaviour of a thread-unsafe class in a multithreaded scenario. We are calling
+ * the increment methods 1000 times from a pool of 3 threads. In most of the cases, the counter will 
+ * less than 1000, because of lost updates, however, occasionally it may reach 1000, when no threads
+ * called the method simultaneously. This may cause the build to fail occasionally. Hence excluding this
+ * test from build by adding this in manual test
+ */
+public class ThreadUnsafeCounterManualTest {
+
+    @Test
+    public void givenMultiThread_whenUnsafeCounterIncrement() throws InterruptedException {
+        ExecutorService service = Executors.newFixedThreadPool(3);
+        UnsafeCounter unsafeCounter = new UnsafeCounter();
+
+        IntStream.range(0, 1000)
+          .forEach(count -> service.submit(unsafeCounter::increment));
+        service.awaitTermination(100, TimeUnit.MILLISECONDS);
+
+        assertEquals(1000, unsafeCounter.getValue());
+    }
+    
+}

core-java/src/test/java/com/baeldung/deserialization/DeserializationUnitTest.java

@@ -12,7 +12,7 @@ import org.junit.Test;
 
 public class DeserializationUnitTest {
 
-    private static final String serializedObj = "rO0ABXNyACljb20uYmFlbGR1bmcuZGVzZXJpYWxpemF0aW9uLkFwcGxlUHJvZHVjdAAAAAAAEtaHAgADTAANaGVhZHBob25lUG9ydHQAEkxqYXZhL2xhbmcvU3RyaW5nO0wADmxpZ2h0ZW5pbmdQb3J0cQB+AAFMAA90aHVuZGVyYm9sdFBvcnRxAH4AAXhwdAARaGVhZHBob25lUG9ydDIwMjBwdAATdGh1bmRlcmJvbHRQb3J0MjAyMA==";
+    private static final String serializedObj = "rO0ABXNyACljb20uYmFlbGR1bmcuZGVzZXJpYWxpemF0aW9uLkFwcGxlUHJvZHVjdAAAAAAAdMuxAgADTAANaGVhZHBob25lUG9ydHQAEkxqYXZhL2xhbmcvU3RyaW5nO0wADWxpZ2h0bmluZ1BvcnRxAH4AAUwAD3RodW5kZXJib2x0UG9ydHEAfgABeHB0ABFoZWFkcGhvbmVQb3J0MjAyMHQAEWxpZ2h0bmluZ1BvcnQyMDIwdAATdGh1bmRlcmJvbHRQb3J0MjAyMA";
 
     private static long userDefinedSerialVersionUID = 1234567L;
 
@@ -25,20 +25,22 @@ public class DeserializationUnitTest {
     public void testDeserializeObj_compatible() throws IOException, ClassNotFoundException {
 
         assertEquals(userDefinedSerialVersionUID, AppleProduct.getSerialVersionUID());
-        
+
         AppleProduct macBook = new AppleProduct();
         macBook.headphonePort = "headphonePort2020";
         macBook.thunderboltPort = "thunderboltPort2020";
-        
+        macBook.lightningPort = "lightningPort2020";
+
         // serializes the "AppleProduct" object
         String serializedProduct = SerializationUtility.serializeObjectToString(macBook);
 
         // deserializes the "AppleProduct" object
         AppleProduct deserializedProduct = (AppleProduct) DeserializationUtility.deSerializeObjectFromString(serializedProduct);
-     
+
         assertTrue(deserializedProduct.headphonePort.equalsIgnoreCase(macBook.headphonePort));
         assertTrue(deserializedProduct.thunderboltPort.equalsIgnoreCase(macBook.thunderboltPort));
-    
+        assertTrue(deserializedProduct.lightningPort.equalsIgnoreCase(macBook.lightningPort));
+
     }
 
     /**
@@ -59,7 +61,6 @@ public class DeserializationUnitTest {
     public void testDeserializeObj_incompatible() throws ClassNotFoundException, IOException {
 
         assertNotEquals(userDefinedSerialVersionUID, AppleProduct.getSerialVersionUID());
-        
         // attempts to deserialize the "AppleProduct" object
         DeserializationUtility.deSerializeObjectFromString(serializedObj);
     }

core-java/src/test/java/com/baeldung/temporaladjusters/CustomTemporalAdjusterTest.java

@@ -1,34 +1,34 @@
 package com.baeldung.temporaladjusters;
 
-import java.time.DayOfWeek;
-import java.time.LocalDate;
-import java.time.Period;
-import java.time.temporal.TemporalAdjuster;
-import java.time.temporal.TemporalAdjusters;
-
+import com.baeldung.temporaladjuster.CustomTemporalAdjuster;
 import org.junit.Assert;
 import org.junit.Test;
 
-import com.baeldung.temporaladjuster.CustomTemporalAdjuster;
+import java.time.LocalDate;
+import java.time.Period;
+import java.time.temporal.TemporalAdjuster;
+
+import static org.junit.Assert.assertEquals;
 
 public class CustomTemporalAdjusterTest {
 
+    private static final TemporalAdjuster NEXT_WORKING_DAY = new CustomTemporalAdjuster();
+
     @Test
     public void whenAdjustAndImplementInterface_thenNextWorkingDay() {
         LocalDate localDate = LocalDate.of(2017, 07, 8);
         CustomTemporalAdjuster temporalAdjuster = new CustomTemporalAdjuster();
         LocalDate nextWorkingDay = localDate.with(temporalAdjuster);
 
-        Assert.assertEquals("2017-07-10", nextWorkingDay.toString());
+        assertEquals("2017-07-10", nextWorkingDay.toString());
     }
 
     @Test
     public void whenAdjust_thenNextWorkingDay() {
         LocalDate localDate = LocalDate.of(2017, 07, 8);
-        TemporalAdjuster temporalAdjuster = NEXT_WORKING_DAY;
-        LocalDate date = localDate.with(temporalAdjuster);
+        LocalDate date = localDate.with(NEXT_WORKING_DAY);
 
-        Assert.assertEquals("2017-07-10", date.toString());
+        assertEquals("2017-07-10", date.toString());
     }
 
     @Test
@@ -39,18 +39,6 @@ public class CustomTemporalAdjusterTest {
 
         String fourteenDaysAfterDate = "2017-07-22";
 
-        Assert.assertEquals(fourteenDaysAfterDate, result.toString());
+        assertEquals(fourteenDaysAfterDate, result.toString());
     }
-
-    static TemporalAdjuster NEXT_WORKING_DAY = TemporalAdjusters.ofDateAdjuster(date -> {
-        DayOfWeek dayOfWeek = date.getDayOfWeek();
-        int daysToAdd;
-        if (dayOfWeek == DayOfWeek.FRIDAY)
-            daysToAdd = 3;
-        else if (dayOfWeek == DayOfWeek.SATURDAY)
-            daysToAdd = 2;
-        else
-            daysToAdd = 1;
-        return date.plusDays(daysToAdd);
-    });
 }