How to pause thread in java?

Question

So what's the best way to pause a thread? So far I have something like this: In main loop of the thread, first line is:

while (paused == true) {
   Thread.sleep(refreshRate);
}

And it works perfercly. I can change paused state pressing P key. But Im looking for better, more professional solution. I know about reentrant locks and conditions. So I could use them on the thread. And then presing P would release singalAll() method. But it would slow my app a lot because of synchronization which I don't really need in this thread. So what is the best, most perform way to solve it? Maybe using synchronization blocks?

synchronized (new Object()) {

}

Then just part of code would be synchronized. Or maybe I should use semaphores?

Whats wrong with Thread.sleep()? do you want tonsleep, or do you want to wait until an action occurs where then to continue? — AlexWien, Feb 17 '13 at 15:14
Wait until action occurs where then to continue is what I want. — user2080377, Feb 17 '13 at 15:28

score 1 · Answer 1 · answered Feb 17 '13 at 15:21

You should use a wait/notify scheme such as:

Create an atomic boolean flag in the thread to be paused.
When the flag is set the thread should call wait() on a lock object
When you want to unpause the thread reset the flag and call notify() on the lock object

score 0 · Answer 2 · edited Dec 09 '13 at 12:47

0

Use wait() and notify()

Object waitLock = new Object();

//...


// waiter Thread
synchronized (waitLock) {
   waitLock.wait();
}


// wake up with

waitLock.notify();

edited Dec 09 '13 at 12:47

BenMorel

34,448
50
182
322

answered Feb 17 '13 at 15:32

AlexWien

28,470
6
53
83

score 0 · Answer 3 · edited May 23 '17 at 12:12

0

Use a PauseableThread like the one I posted a while ago in answer to a question much like yours.

It uses ReadWriteLocks to implement so you don't have the overhead of synchronization.

edited May 23 '17 at 12:12

Community

1
1

answered Feb 17 '13 at 16:09

OldCurmudgeon

64,482
16
119
213

How to pause thread in java?

3 Answers3