Multithreading

Multithreading

I have 3 functions

1.Zip a folder
2.Create Hash for the zipped file with same file name but append with .txt instead of .zip
3.Upload the zip and hash file.

All these have to be executed in threads so that multiple folders can be zipped, hashed and uploaded simultaneously.

I should be able to set the maximum no: of threads allowed.

Also I should be able to queue the threads if new one's created and already the maximum no: of allowed threads are running. Once a thread completes execution, it should be able to notify the queue and a thread from the queue should start executing.

Any help in this direction will be greatly appreciated.
Many thanks in advance.

Ron.