https://www.bignerdranch.com/blog/the-rxjava-repository-pattern/
Still, if you are trying to implement the repository patter in your own project for a first time it's a lot to wrap your head around. In that case, maybe a very interesting library to take a look at is NYTimes' Store which will make implementing caching, persistant storage and reactive data loading a lot easier for you:
Github:
https://github.com/NYTimes/Store
