My aim is to package FreeMind and Freeplane, two Mind Mappers written in Java and placed under GPLv2+

FreeMind: http://freemind.sf.net/
Freeplane: http://freeplane.sf.net/

SimplyHTML is an application and a java component for rich text processing. It stores documents as HTML files in combination with Cascading Style Sheets (CSS). SimplyHTML is not intended to be used as an editor for web pages.
Homepage: http://simplyhtml.sf.net/

And SimplyHTML is incidentally a dependency of FreeMind.