multithreading - How to stop all runnable thread in java executor class?

Question

final ExecutorService executor = Executors.newFixedThreadPool(1);
final Future<?> future = executor.submit(myRunnable);
executor.shutdown();
if(executor.awaitTermination(10, TimeUnit.SECONDS)) {
  System.out.println("task completed");
}else{
  System.out.println("Executor is shutdown now");
}

//MyRunnable method is defined as task which I want to execute in a different thread.

Here is run method of executor class:

public void run() {
try {
     Thread.sleep(20 * 1000);
} catch (InterruptedException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
}}

Here it is waiting for 20 second but when i run the code it throws an exception:

java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)

I am not able to close the concurrent thread ruining in Java Executor class. Here is my Code flow:

• Created a new Thread with Java executor class to run some task i.e written in MyRunnable
• executor wait for 10 second to complete the tasks.
• If the task has completed then runnable thread also got terminated.
• If the task is not completed within 10 second then executor class should terminate the thread.

Everything works fine except the termination of tasks in the last scenario. How should I do it?

Answer 1

The shutDown() method simply prevents additional tasks from being scheduled. Instead, you could call shutDownNow() and check for thread interruption in your Runnable.

// in your Runnable...
if (Thread.interrupted()) {
  // Executor has probably asked us to stop
}

An example, based on your code, might be:

final ExecutorService executor = Executors.newFixedThreadPool(1);
executor.submit(new Runnable() {
  public void run() {
    try {
      Thread.sleep(20 * 1000);
    } catch (InterruptedException e) {
      System.out.println("Interrupted, so exiting.");
    }
  }
});

if (executor.awaitTermination(10, TimeUnit.SECONDS)) {
  System.out.println("task completed");
} else {
  System.out.println("Forcing shutdown...");
  executor.shutdownNow();
}