It might be worth a look at Immutables (http://immutables.github.io/ http://immutables.github.io/) or FreeBuilder (https://github.com/google/FreeBuilder https:/

It might be worth a look at Immutables (http://immutables.github.io/ http://immutables.github.io/) or FreeBuilder (https://github.com/google/FreeBuilder https://github.com/google/FreeBuilder), both of which also use Java's built-in annotation processors to do code generation, but involve slightly less magic and produce generated classes which are not overwriting the original class.