Merge branch 'master' into BAEL-614

core-java/src/main/java/com/baeldung/concurrent/blockingqueue/BlockingQueueUsage.java

@@ -1,6 +1,5 @@
 package com.baeldung.concurrent.blockingqueue;
 
-
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 
@@ -12,7 +11,6 @@ public class BlockingQueueUsage {
         int poisonPill = Integer.MAX_VALUE;
         int poisonPillPerProducer = N_CONSUMERS / N_PRODUCERS;
 
-
         BlockingQueue<Integer> queue = new LinkedBlockingQueue<>(BOUND);
 
         for (int i = 0; i < N_PRODUCERS; i++) {

core-java/src/main/java/com/baeldung/concurrent/blockingqueue/NumbersConsumer.java

@@ -1,9 +1,8 @@
 package com.baeldung.concurrent.blockingqueue;
 
-
 import java.util.concurrent.BlockingQueue;
 
-class NumbersConsumer implements Runnable {
+public class NumbersConsumer implements Runnable {
     private final BlockingQueue<Integer> queue;
     private final int poisonPill;
 
@@ -21,7 +20,6 @@ class NumbersConsumer implements Runnable {
                 }
                 String result = number.toString();
                 System.out.println(Thread.currentThread().getName() + " result: " + result);
-
             }
         } catch (InterruptedException e) {
             Thread.currentThread().interrupt();

core-java/src/main/java/com/baeldung/concurrent/blockingqueue/NumbersProducer.java

@@ -1,23 +1,22 @@
 package com.baeldung.concurrent.blockingqueue;
 
-
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ThreadLocalRandom;
 
+public class NumbersProducer implements Runnable {
 
 class NumbersProducer implements Runnable {
+
     private final BlockingQueue<Integer> numbersQueue;
     private final int poisonPill;
     private final int poisonPillPerProducer;
 
-
     public NumbersProducer(BlockingQueue<Integer> numbersQueue, int poisonPill, int poisonPillPerProducer) {
         this.numbersQueue = numbersQueue;
         this.poisonPill = poisonPill;
         this.poisonPillPerProducer = poisonPillPerProducer;
     }
 
-
     public void run() {
         try {
             generateNumbers();

core-java/src/main/java/com/baeldung/concurrent/countdownlatch/Worker.java

@@ -16,7 +16,7 @@ public class Worker implements Runnable {
     public void run() {
         // Do some work
         System.out.println("Doing some logic");
-        countDownLatch.countDown();
         outputScraper.add("Counted down");
+        countDownLatch.countDown();
     }
 }

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

@@ -0,0 +1,26 @@
+package com.baeldung.concurrent.future;
+
+import java.util.concurrent.RecursiveTask;
+
+public class FactorialSquareCalculator extends RecursiveTask<Integer> {
+    private static final long serialVersionUID = 1L;
+
+    final private Integer n;
+
+    public FactorialSquareCalculator(Integer n) {
+        this.n = n;
+    }
+
+    @Override
+    protected Integer compute() {
+        if (n <= 1) {
+            return n;
+        }
+
+        FactorialSquareCalculator calculator = new FactorialSquareCalculator(n - 1);
+
+        calculator.fork();
+
+        return n * n + calculator.join();
+    }
+}

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

@@ -0,0 +1,24 @@
+package com.baeldung.concurrent.future;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+
+public class SquareCalculator {
+    
+    private final ExecutorService executor;
+    
+    public SquareCalculator(ExecutorService executor) {
+        this.executor = executor;
+    }
+    
+    public Future<Integer> calculate(Integer input) {        
+        return executor.submit(new Callable<Integer>() {
+            @Override
+            public Integer call() throws Exception {
+                Thread.sleep(1000);
+                return input * input;
+            }
+        });
+    }
+}