Oftentimes, I think it would be ideal if Chickenfoot did not depend on Java -- it would be a smaller download and simpler to install. Recently, we've been trying to break that dependency, but we haven't been successful yet. But then again, is it really so bad? With Java installed, you can call Swing from Chickenfoot.
I once had a 6.170 student who tried to use Jython to prototype Swing GUIs so he could script them and add components on the fly instead of rebuilding the app each time he wanted to add a component -- this is basically the same idea (though calling Java from Chickenfoot is a bit sluggish). This is mainly a proof-of-concept of calling Java from Chickenfoot -- if you really want a Java interpreter, I'd recommend BeanShell or DrJava (the Eclipse plugin, of course).