From the beginning, Sun has only worked on making it work on Windows and Solaris. Other versions were released but the mac version was so laughably lame as to be completely unusable.
Swing remains laughably lame.
Rather than work on the core and make it good, Sun has been busy trying to take over the world with no less avarice than MS. While they like to characterize themselves as the good guys, I believe they ought to change their motto to "Sun, the other Microsoft".