Displaying html, even just for help pages, through Swing's JEditorPane stinks. It's slow, you have to program much of the functionality yourself, and no matter how you end up doing it, you end up with a sorry substitute for a browser.

SWT is one alternative, but that's a lot of overhead for one simple widget. If you're not going whole hog to SWT, you're probably still better off with a simple JEditorPane.

OR -- Use something native with a thin JNI wrapper. Sound difficult? Esoteric? Relatively speaking, it is. Luckily, for Mac OS X, we've got this example code from Dmitry Markman showing how to use the WebKit (Safari) via Cocoa in Java code.

Not "Java Pure", but a great, robust browser in your app.