Need help to write a unit test using Mockito and JUnit4

Question

Need help to write a unit test for the below code using Mockito and JUnit4,

public class MyFragmentPresenterImpl { 
      public Boolean isValid(String value         


        

Answer 1

As a followup to Johnny's answer, to catch TextUtils.isEmpty(null) calls as well, you could use this piece of code.

PowerMockito.mockStatic(TextUtils.class);
PowerMockito.when(TextUtils.isEmpty(any()))
    .thenAnswer((Answer) invocation -> {
        Object s = invocation.getArguments()[0];
        return s == null || s.length() == 0;
    });