Access to Gecko/WebKit in Java?

I know this has been asked before, but they are all higher level than I want.

I want to handle ALL of the networking(HTTP/S, DNS, etc), not just do something like browser.load("http://ift.tt/gbk8l4");

I wouldn't mind doing the rendering myself, but I can't find any detailed and universal specifications. I would also like if possible to NOT be forced to use Swing or other, as I think I want to work closer to the hardware with a OpenGL wrapper.