I'm working on a university research project, but I wanna enhance the user interface, namely by adding AJAX. I'm working with servlets and JPS, but I need some recommendation on which libraries to use for AJAX if there is anything out there that makes life easier :).
All depends on the level of learning curve.
low level learning curve use Prototype
medium level, use jquery
high level, use scriptaculous or dojo
Honestly though, if you're looking for eye candy features than I'd use scriptaculous. jQuery can achieve the same but you need to install plugins for it (or not... haven't really checked out their UI package)