calling Thread.sleep() from synchronized context in Java

Question

I have read that Thread.sleep() will pause the currently running thread for the time specified after which it goes back to runnable state waiting for it\'s turn

Answer 1

So I was wondering when it will release the lock.

It will release the lock upon exit from the synchronized block, and not earlier.

If the thread, put on sleep, never gets the chance to run so it will always keep the lock with itself and then how other threads get to enter synchronized methods/block.

Quite simply, other threads will not be able to enter code that's synchronized on the same object that the sleeping thread.

To summarize, calling Thread.sleep() from a synchronized block is likely not a good idea.

Answer 2

If you use Object.wait instead of Thread.sleep, the lock from the synchronized block will be released.