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Unexpected result with Threads join() method...

Paul Callaly

Joined: Dec 16, 2003
Posts: 12
In theory I understand the way Threads join() method works, but when I am testing it with some code, I am getting unexpected results. I thought if you say:
1. start a thread1
2. start a thread2
3 do thread2.join()
I thought the result would be thread1 will pause until thread2 finishes then go back to runnable and eventually finish. Here's my code with an exlanation of results:

No matter how I change the for loop counter int in run(), Fred always finishes before Lucy. Surely he has joined the end of Lucy and must wait till she finishes.
Thanx for any help
Abdulla Mamuwala
Ranch Hand

Joined: Jan 09, 2004
Posts: 225
What you have stated about the join() method is exactly right.
The analysis of your code can be done as follows:
There are 3 threads running namely,
1>main thread
2>Fred thread
3>Lucy thread
The code starts the threads "Fred" and "Lucy" in the "main" thread.
Therefore,we call the join() method on the "main" thread and not on the thread named "Fred".Hence there is nothing you can do with the run() method.
I agree. Here's the link:
subject: Unexpected result with Threads join() method...
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