J2SE and Widgets

I am working on creating a JWidget class and am looking for the correct base class. I want my widget to be always on top, not appear in the windows task bar, have no decorations and accept both mouse and keyboard input. I have investigated JFrame, JWindow and JDialog on J2SE 1.4.2 and J2SE 5. here are the results:

J2SE 1.4.2

Feature	JFrame	JWindow	JDialog
Invisible on task bar	NO	YES	YES
can be always on top	NO	NO	NO
No Decorations	YES	YES	NO
Accepts mouse input	YES	YES	YES
Accepts keyboard input	YES	NO	YES

J2SE 5

Feature	JFrame	JWindow	JDialog
Invisible on task bar	NO	YES	YES
can be always on top	YES	YES*	YES
No Decorations	YES	YES	YES
Accepts mouse input	YES	YES	YES
Accepts keyboard input	YES	NO	YES

(*) must always be on top.

Unfortunately there are some considerable differences between 1.4.2 and 5. I might want to limit my JWidget class to 1.4.2 functionality to support OS X. more on that later. Provided J2SE is an option, it looks like JDialog is the way to go, though JFrame is perfectly acceptable if being invisible on the task bar is not a concern. I admit I was surprised that JDialog would meet all my requirements, I am going to do some more investigating to make sure that JDialog does not perform oddly on the different platforms.

Also, since these different pieces of functionality are provided by different classes. It looks as though making sensible methods like setVisibleOnTaskBar() will be impossible.