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threading problem

fadi mujahid

Joined: Oct 14, 2002
Posts: 28
I am almost done with my SCJD assignment and I am testing it thoroughly. I am facing the following problem that is occuring randomly:
I am using wait(), notifyAll() for my lock/unlock operations.
Randomly, one of the threads gets stuck in the wait() status and wouldn't gets activated although I call notifyAll at the unlock.
Any suggestion?
Rama Ituarte
Ranch Hand

Joined: Apr 10, 2002
Posts: 62
Are you sure that your unlock is being called, even if an exception occurs?
parthiban subramaniam
Ranch Hand

Joined: May 15, 2002
Posts: 116
hi fadi,
instead of catching for specific exceptions try to catch Throwable and print the stacktrace of it to track down things .. am sure something exception is going un noticed in your coded creating these problems.
hope this helps,


Even crazy and silly looking problems are sometimes real.
fadi mujahid

Joined: Oct 14, 2002
Posts: 28
Thank you very much for your help. I finally figured it out: I was wait()ing the object Data, and notifyAll() on object locks!!!
This stupid problem cost me more than 20 hours of debugging.
Thanks again
I agree. Here's the link:
subject: threading problem
It's not a secret anymore!