Hello all,
We have created a java app that creates its own file format that we can assoicate with the application in Windows. We would like for the user to be able to double click on of these files while the app is running and have the app open it. We are at a loss of how to do this with out opening another session of app, which is what we are trying to avoid. Any help, tips, webpages to read, anything to try would be super helpful.

Thanks,
Menlo

You'd have to have some JNI hook into the Windows subsystem that governs these operations.
Hardly a trivial task.