How can I (natively) implement the fullscreen feature of OSX Lion in a Java application?
The current answers given incorporate a good method for achieving a sort-of-
I don't know about natively, but Java does support fullscreen applications without needing native code:
http://saipullabhotla.blogspot.com/2012/05/enabling-full-screen-mode-for-java.html
The question is has Apple implemented that with Lion in their JDK.