timer and timertask examples

Author: eugenp

core-java/src/test/java/org/baeldung/java/JavaTimerUnitTest.java

@@ -3,6 +3,9 @@
 import java.util.Date;
 import java.util.Timer;
 import java.util.TimerTask;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 
 import org.junit.Test;
 
@@ -15,16 +18,102 @@ public void givenUsingTimer_whenSchedulingTaskOnce_thenCorrect() throws Interrup
         final TimerTask timerTask = new TimerTask() {
             @Override
             public void run() {
-                System.out.println("Task performed on " + new Date() + "\n" + "Thread's name: " + Thread.currentThread().getName());
+                System.out.println("Task performed on: " + new Date() + "\n" + "Thread's name: " + Thread.currentThread().getName());
             }
         };
-
         final Timer timer = new Timer("Timer");
+
         final long delay = 1000L;
         timer.schedule(timerTask, delay);
 
         Thread.sleep(delay * 2);
         timer.cancel();
     }
 
+    @Test
+    public void givenUsingTimer_whenSchedulingRepeatedTask_thenCorrect() throws InterruptedException {
+        final TimerTask repeatedTask = new TimerTask() {
+            @Override
+            public void run() {
+                System.out.println("Task performed on " + new Date());
+            }
+        };
+        final Timer timer = new Timer("Timer");
+
+        final long delay = 1000L;
+        final long period = 1000L;
+        timer.scheduleAtFixedRate(repeatedTask, delay, period);
+
+        Thread.sleep(delay * 2);
+        timer.cancel();
+    }
+
+    @Test
+    public void givenUsingTimer_whenSchedulingDailyTask_thenCorrect() throws InterruptedException {
+        final TimerTask repeatedTask = new TimerTask() {
+            @Override
+            public void run() {
+                System.out.println("Task performed on " + new Date());
+            }
+        };
+        final Timer timer = new Timer("Timer");
+
+        final long delay = 1000L;
+        final long period = 1000L * 60L * 60L * 24L;
+        timer.scheduleAtFixedRate(repeatedTask, delay, period);
+
+        Thread.sleep(delay * 2);
+        timer.cancel();
+    }
+
+    @Test
+    public void givenUsingTimer_whenCancelingTimerTask_thenCorrect() throws InterruptedException {
+        final TimerTask task = new TimerTask() {
+            @Override
+            public void run() {
+                System.out.println("Task performed on " + new Date());
+                cancel();
+            }
+        };
+        final Timer timer = new Timer("Timer");
+
+        final long delay = 1000L;
+        final long period = 1000L;
+        timer.scheduleAtFixedRate(task, delay, period);
+
+        Thread.sleep(delay * 3);
+    }
+
+    @Test
+    public void givenUsingTimer_whenCancelingTimer_thenCorrect() throws InterruptedException {
+        final TimerTask task = new TimerTask() {
+            @Override
+            public void run() {
+                System.out.println("Task performed on " + new Date());
+            }
+        };
+        final Timer timer = new Timer("Timer");
+
+        timer.scheduleAtFixedRate(task, 1000L, 1000L);
+
+        Thread.sleep(1000L * 2);
+        timer.cancel();
+    }
+
+    @Test
+    public void givenUsingExecutorService_whenSchedulingRepeatedTask_thenCorrect() throws InterruptedException {
+        final TimerTask repeatedTask = new TimerTask() {
+            @Override
+            public void run() {
+                System.out.println("Task performed on " + new Date());
+            }
+        };
+        final ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
+        final long delay = 1000L;
+        final long period = 1000L;
+        executor.scheduleAtFixedRate(repeatedTask, delay, period, TimeUnit.MILLISECONDS);
+        Thread.sleep(delay + period * 3);
+        executor.shutdown();
+    }
+
 }