I last used it a good while ago (like, 10yrs?), so you'll have to verify how what I am about to say applies to current versions (it probably does).

Jasper is an old-school, enterprisey tool similar to Crystal Reports that attempts to give you a WYSIWYG editor for building your reports.

All in all, I'd say that it might be good if you have a reporting department full of people that only do reports and you don't want to train as programmers. If the ones doing the reports are gonna be actual programmers, they'll be much better off generating html/latex/whatever and converting that to pdf.