runexec.(filepath) open random locations in desktop?

I am using the "Process process = runtime.exec("C:\Windows\notepad.exe");" command in Java and was wondering if there was a way I can have it open at random locations upon the desktop, I am working on a harmless virus project for class and have the program making 100 instances of this but all appearing at same location, how can I randomize this? Thanks and sorry for stupid question, Google search didn't help me.