IllegalMonitorStateException on wait() call

Question

I am using multi-threading in java for my program. I have run thread successfully but when I am using Thread.wait(), it is throwing java.lang.IllegalMonit

Answer 1

Not sure if this will help somebody else out or not but this was the key part to fix my problem in user "Tom Hawtin - tacklin"'s answer above:

synchronized (lock) {
    makeWakeupNeeded();
    lock.notifyAll();
}

Just the fact that the "lock" is passed as an argument in synchronized() and it is also used in "lock".notifyAll();

Once I made it in those 2 places I got it working