Good Day.
I'm an experienced java developer (4 years). I've worked with several web technologies, like JSF, Hibernate and JasperReports.
Jasper Reports supports JFreeChart and that can be used to create the desired graphs. Can be customized using a java customizer, without much hassle. With this reporter, is possible to use SQL queries to get data or HQL using an included hibernate module (in a jar).
With the adecuate programming, a massive report generation can be configured for tomcat, generating PDF reports for example and zipping them for download.
As an additional comment, I've done several projects here at Freelancer.com. Please check my profile.
Thanks for your attention.