How to wake up a thread before time is up

Question

i am working on a Java application and i reach a point where i want to pause the execution for few seconds ( chosen by the user ) and resume it latter ..and here is a simple code :

Public Class myApp
{
    static public main()
    { 
       int seconds=10;
       // do couple of things 
       try {
                   Thread.sleep(10*1000);
               } catch (InterruptedException ex) {

                   Logger.getLogger(myApp.class.getName()).log(Level.SEVERE,    null,      ex);
               }
    }

i want now to give the user a chance by clicking on a button to resume the execution even before the time is up . is this possible using "Thread.sleep()" ? or there is another way to pause App and resume it ?

You will need to interrupt the thread, but you may also want to reset the interrupted flag by calling [`Thread#interrupted`](http://docs.oracle.com/javase/7/docs/api/java/lang/Thread.html#interrupted()) — MadProgrammer, Sep 24 '13 at 03:23
@MadProgrammer if i interrupt the thread, will make it resume even if the Thread is sleeping ? — user2746896, Sep 24 '13 at 03:25
You need to interrupt the "sleeping" thread. But yes, that's why you need to catch `InterruptedException`, so you know when the thread was woken prematurely... — MadProgrammer, Sep 24 '13 at 03:27
@MadProgrammer uh i see ...Thread.currentThread().interrupt(); is that how do i interrupt the main Thread ? — user2746896, Sep 24 '13 at 03:31
The problem with what you just said is, `Thread.currentThread` is asleep... — MadProgrammer, Sep 24 '13 at 03:35

score 1 · Answer 1 · answered Sep 24 '13 at 03:23

1

You can use wait in place of sleep to pause the thread execution. Then you can use notify or notifyAll to wake up the waiting thread.

answered Sep 24 '13 at 03:23

Terry Li

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How can i use wait with Main() ? – user2746896 Sep 24 '13 at 03:27
@MadProgrammer can you tell me how could i do it with "main()" ? i mean how to make it wait for some seconds ... i m still new with those notions ..thank you – user2746896 Sep 24 '13 at 03:33
@user2746896 [This post](http://stackoverflow.com/questions/1036754/difference-between-wait-and-sleep) may give you an idea :) – Terry Li Sep 24 '13 at 03:48

score 1 · Accepted Answer · answered Sep 24 '13 at 03:36

1

Use CountDownLatch

Public Class myApp
{
    static CountDownLatch countDownLatch = new CountDownLatch(1);

    static public main()
    {        
       try {
            countDownLatch.await(10000, TimeUnit.MILLISECONDS);
       } catch (InterruptedException ex) {
            // Logging
       }
    }
}

and you can call countDownLatch.countDown() method from the resume button on click

answered Sep 24 '13 at 03:36

shazin

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You can do this with sleep as well, as wait/notify and many other options. – Peter Lawrey Sep 24 '13 at 04:49

score 0 · Answer 3 · answered Sep 24 '13 at 03:25

0

You can use interrupt to cancel the sleep, here are more info: http://docs.oracle.com/javase/tutorial/essential/concurrency/interrupt.html

answered Sep 24 '13 at 03:25

stdapsy

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How to wake up a thread before time is up

3 Answers3