AndroMDA is a an XDoclet generator. It generates XDoclet code and then XDoclet generates from that. We talk about AndroMDA and middlegen (generating from models and from relational schema, respectively) in chapter 13 of the book.
For a good view of the code generation landscape beyond XDoclet, check out
the code generation network. Jack does a good job of tracking the various code generation tools and frameworks out there. If you are interested in code generation, I highly recommend
Code Generation in Action. It's more about techniques than tools, but it's a good broad overview. Of course
you should buy and read XDoclet in Action first...