Have you ever try JCreator? It has several packages
depended on your OS. But we have to think about it
nothing absolutely free, it is just liked any other
packages, only a teaser. If you are a student then
the JCreator LE is enough, but if you are a pro then
you needs to pay a little token.

Of all the Java IDE, I think JCreator is the best
because it does not developed any code for you. It
only help you handle the mundane tasks so you could
concentrate on your logic.