IMHO, I don’t think there are enough code generators, however, a good code generator’s output should be a library, not editable source. I’ve had a lot of good experience using IDLs that could generate libraries for multiple languages that other code could be used with (e.g. define your REST url scheme and supported operations and a base class that gets generated that allows filling in logic).

At least in Java world, annotation seemed to have taken over, but the mixture of code and interface definition kicks you into the language and allows too much flexibility that really make it no different than writing registration code. Having a nice declarative language without business logic sneaking in.