I'm looking for design suggestions to this problem...

I have a JFrame which needs to launch a JDialog. When the JDialog
launches I need to run some processing based on the contents of the
JFrame. The JDialog has options like next, previous, etc... Now, the
problem is that I want the JDialog to remain on top, so I was
considering a modal JDialog. The problem is that a modal JDialog
blocks, but I need to have processing running in the background based
on response to the user input, next, previous, etc. Should I create a
separate thread? Where should this thread be created?

Thanks!

Jay.