Calling Thread doesn't stop after RejectedExecutionException

Question

Why main thread is not stopped when one of the thread from threadpool throws RejectedExecutionException ?Am i doing something wrong here? 3rd thread in the threadpool is throwing RejectedExecutionException and i am not handling this exception in main thread. So do i necessarily handle this exception to make my main thread stop. Any help would be appreciated.

    public static void main(String[] args) {
        ExecutorService threadPool = new ThreadPoolExecutor(1, 1, 0L, TimeUnit.MILLISECONDS,
                new ArrayBlockingQueue<Runnable>(1));
        threadPool.execute(new TestOne());
        threadPool.execute(new TestTwo());
        threadPool.execute(new TestThree());
        threadPool.shutdown();
        try {
            threadPool.awaitTermination(2L, TimeUnit.SECONDS);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        System.out.println("main thread stopped");
    }
}

class TestOne implements Runnable {
    public void run() {
        for (int i = 0; i < 10; i++) {
            System.out.println("Executing task one");
            try {
                Thread.sleep(10);
            } catch (Throwable e) {
                e.printStackTrace();
            }
        }

    }
}

class TestTwo implements Runnable {
    public void run() {
        for (int i = 0; i < 10; i++) {
            System.out.println("Executing task two");
            try {
                Thread.sleep(10);
            } catch (Throwable e) {
                e.printStackTrace();
            }
        }
    }
}

class TestThree implements Runnable {
    public void run() {
        for (int i = 0; i < 10; i++) {
            System.out.println("Executing task three");
            try {
                Thread.sleep(10);
            } catch (Throwable e) {
                e.printStackTrace();
            }
        }
    }
}

Answer 1

No threads from the thread pool are throwing a RejectedExecutionException . The main thread which is submitting the tasks to the thread pool is actually throwing the RejectedExecutionException .

The main thread will not block on submission as the spec's dictate it should not. There are mechanisms to do this, see ThreadPoolExecutor Block When Queue Is Full?