Basic of Mockito: https://github.com/in28minutes/MockitoTutorialForBeginnersWrite basic Junit test case and mocking service inside test classhttps://www.youtube.com/watch?v=d2KwvXQgQx4Testing rest Api's using spring framework mockmvc.https://www.youtube.com/watch?v=8S8o46avgAwhttps://stackoverflow.com/questions/18164123/how-to-clean-up-mocks-in-spring-tests-when-using-mockitohttps://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html