Parser generators

Building a drag-and-drop, visual editor for Java/CoffeeScript will require a smart parser.
It's likely none will work out of the box, since we need whitespace and comments to be preserved.

It will also need to be fully, losslessly bidirectional.

However, it's best to fork rather than rewrite, so here are some promising parser generators or javascript parsers

All three look good, perhaps equal. CoffeeScript uses Jison, which is a vote of confidence. TileScript, a bidirectional language, uses OMeta, another good upvote.