Creating a help JDialog

I am looking at having to create a help JDialog that is similar to Eclipse, but a bit simpler but it does need to dynamically load help file as plugins get activated.

I was hoping there is a library that handles the heavy lifting. I had no luck searching for one, is there one?

Is it easier to display content that use HTML or plain text?

I am going to mirror this process with loading plugins which follows a package convention plugins.<name of plugin>.<plugin name which implements a plug in interface>. Something like help/plugin name/list of topics&subtopics and help/plugin name/help files that mirror topic/subtopics name. If this makes sense to you, does this sound like I am on the right track?

How about using JavaHelp that seems to provide dynamic merging of helpsets.