There is a bug in Sun Java's Swing. It doesn't like certain window managers. Something about reparenting and not reparenting or something like that. Whatever. The point is, when trying to run a program you wrote using Swing, all you get is a big white nothing. Nothing draws in the window. Ahhh! What's wrong?! Yeah, I had some trouble with my Java class because of that one. Well, unfortunately, my favourite WM, Beryl, is a problem child with this. However, there is an easy fix for it. Open your .bashrc (that in ~). If you don't know how, do this in the terminal:
gksudu gedit ~/.bashrc Add this line to it:
Now try to run your program again. Now everything works. Yay!