Mockito

Most important idea

Reference

Most important idea

1. mockito can test interface, we don't even need a Collection object here.
2. black box, focus on behaviour.
3. no real stuff is save into the mock object.
4. spy on real stuff, but not modify it.

Reference

https://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html