I dont need a loader. A loader would impose a particular scene graph structure on every app i would made. Just read the xml doc with the sax driver and when you encounter the relevant sections insert java3d code to build the scene graph directly.
Erm, i don't get what your saying, a loader will just return you a node when you ask it to load a model, what you do with it after that is up to you. Doing the java3d code yourself you are writing a loader, but then forcing it into the scene graph, a loader is probably more flexible than what you suggest (I've got some user providable node handlers for special circumstances in my ac3d loader).
Just my 2p worth.