[aerogear-dev] [Android] Interfaces on Pipeline, Datamanager, and Authenticator

(See https://github.com/aerogear/aerogear-android/pull/33)[Yes it isn't coarsely separated, it is just a bunch of proof of concept stuff] Right now in ag-android Pipeline and DataManager are final and concrete. Authenticator is an interface implemented by the final class DefaultAuthenticator. I have coded up a proposal where I've (among other things) split the other classes up. Pros for Interface + final class: Easier mocking for unit tests (thinking about users' unit tests not ours) Better practice (is Josh Bloch is to be belived) Cons: Pipeline et all are entry point classes and we shouldn't encourage our users to write their own We can make Pipeline et all non-final to allow users to mock them for their tests. Thoughts from the list?