BAEL-6721 move code to concurrency basic folder

core-java-modules/core-java-concurrency-basic/src/test/java/com/baeldung/concurrent/notificationforcompletetask/NotificationsForCompleteTasksUnitTest.java

@@ -0,0 +1,45 @@
+package com.baeldung.concurrent.notificationforcompletetask;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.FutureTask;
+
+import org.junit.Test;
+
+public class NotificationsForCompleteTasksUnitTest {
+
+    @Test
+    public void whenImplementingRunnable_thenReceiveNotificationOfCompletedTask() {
+        Task task = new Task();
+        Callback callback = new Callback();
+        RunnableImpl runnableImpl = new RunnableImpl(task, callback, "ready for next task");
+        runnableImpl.run();
+    }
+
+    @Test
+    public void whenUsingCompletableFuture_thenReceiveNotificationOfCompletedTask() {
+        Task task = new Task();
+        Callback callback = new Callback();
+        CompletableFuture.runAsync(task)
+          .thenAccept(result -> callback.taskDone("completion details: " + result));
+    }
+
+    @Test
+    public void whenUsingThreadPoolExecutor_thenReceiveNotificationOfCompletedTask(){
+        Task task = new Task();
+        Callback callback = new Callback();
+        AlertingThreadPoolExecutor executor = new AlertingThreadPoolExecutor(callback);
+        executor.submit(task);
+    }
+
+    @Test
+    public void whenUsingFutureTask_thenReceiveNotificationOfCompletedTask(){
+        Task task = new Task();
+        Callback callback = new Callback();
+        FutureTask<String> future = new AlertingFutureTask(task, callback);
+        ExecutorService executor = Executors.newSingleThreadExecutor();
+        executor.submit(future);
+    }
+
+}