To be honest, I'd use GWT ( http://code.google.com/webtoolkit/overview.html ) for this kind of thing. Does the same thing, only it's Java -> Javascript. Been around for four years now, and hell, it's Google. Their documentation is excellent, for a start. If I weren't so comfortable in Java, though, I'd definitely think about using this.
I think code bases that use C and those that use Java probably solve very different problems, though. No one is writing 3D engines in Java.
Actually there is, I can't remember the name right now but there is a 3D engine build in Java (it runs on top of OpenGl, but that is just used to draw and interact with the graphic card).