I'm developing an android application by following the Clean Architecture by uncle bob. One of the principles of the clean architecture is the Domain layer uses "pure java" and don't use android classes to increase test-ability. My problem is that one of my use cases should receive Bitmap as input and Bitmap exists only under the android package which is not available to me. my data layer should receive the Bitmap from the domain layer. Is there an object to bridge between the java and android packages?