each time you create a thread and start it, add its reference into a ArrayList.
After the last thread is created, start browsing your arraylist and do a isAlive() test to check if you've got thread running, each a thread is finishing
JianJunShen
ASKER
The answer touches the point. It is clear and solving the problem!! Thanks!!!
Below URL has the example to determine when a thread has finished
http://www.exampledepot.com/egs/java.lang/IfStopped.html