Create graph Editor

I want to create a graph editor written in Java.

In this editor I want the possibility that nodes can contain other nodes. The possibility to define a palette with object, and the possibility to define object in the palette at runtime.

I'm starting with GMF in Eclipse but I'v开发者_StackOverflow中文版e some doubt, is it better to use JUNG2 or something else?

I used JGraphX once, it's very nice and develops constantly. It provides all that you described (you can even find example with the pallete in downloaded package).