There are a lot of open-source projects such as Wordpress, vBulletin, Fusion Ticket, Front Accounting, etc. These are all web applications devised for LAMP platforms, i.e., they are developed in the PHP language and use PDO to access a database (and typically demand a MySQL engine).
However, I am seeking applications like the ones I described, but that are written in Java (hence requiring Apache Tomcat) and access their databases using JDBC (preferably accessing a Postgresql engine). Also like the examples I mentioned, I also need them to be open source. If you know about an application that also fits the criteria but is not an example of the ones I gave, I would also like to learn about it.
Many thanks in advance.
Added: Found what I was looking for:
Added: found more: