This is made for a school project. It uses SDL2 under Java using JNA library. The main bindings are from libjsdl which is an attempt to create an interface for SDL2 using JNA but it lacks documentation and demonstration (still a great project). Some SDL2_mixer bindings are also created using JNA, which is not part of the libjsdl. (see Audio.java)
I hope this proves to be a good demonstration for using libjsdl and JNA.