IOfferManager+OfferManager OfferManager+OfferManagerImpl OfferManafer+ImplOfferManager OfferManager+RealOfferManager

2) but oftentimes a name like that suggests the I terrace is not needed.

2ish OfferManager + DefaultOfferManager (real) + FakeOfferManager (test)

I prefer/use the last one

OfferManager+AndroidOfferManager OfferManager+FakeOfferManager OfferManager+StubOfferManager

pshhh, naming is easy

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