[tizzy]

It’s definitely a bit annoying and verbose in Java but I think creating an interface to support testing is a net positive. That interface is the specification of what that concrete class requires it’s dependencies to do.

I think all the dependencies of a class should define behaviour not implementation so it’s not tightly coupled and can be modified in the future. If you have a class that injects LookUpService, why not put an interface LookUpper in front of it? It’s a layer of indirection but we have IDEs now and reading the interface should be easier or at least provide context.