Mockito - Mock not being injected for one of the testcases

Question

I have a jsf spring application and using mockito for my unit test. I keep getting NullPointerException when i run my junit test in iEmployeeService mocking. There are not Exception for iSecurityLoginService.

Method to be mocked

@Autowired
IEmployeeService iEmployeeService;
@Autowired
ISecurityLoginService iSecurityLoginService;
public void addEvent() {

    entityEventsCreate.setTitle(entityEventsCreate.getTitle());
    entityEventsCreate.setModifiedBy(iSecurityLoginService
                .findLoggedInUserId());

    int eventId = iEmployeeService.addEmployeeTimeOff(entityEventsCreate);
}

My JUnit test is annotated with @RunWith(MockitoJUnitRunner.class)

@Mock
ISecurityLoginService iSecurityLoginService;

@Mock
IEmployeeService iEmployeeService;

@InjectMocks
ServiceCalendarViewBean serviceCalendarViewBean  = new ServiceCalendarViewBean();

@Before public void initMocks() {
           MockitoAnnotations.initMocks(this);
}

@Test
public void testSaveEvent() {
    Mockito.when(iSecurityLoginService.findLoggedInUserId()).thenReturn(1);
    serviceCalendarViewBean.getEntityEventsCreate().setTitle("Junit Event Testing");

    Mockito.when(iSecurityLoginService.findLoggedInUserId()).thenReturn(1);
    Mockito.when(iEmployeeService.addEmployeeTimeOff(Mockito.any(Events.class))).thenReturn(2);

    serviceCalendarViewBean.addEvent();
}

Answer 1

Not related to the question, but useful to know !

If the test is annotated with @RunWith(MockitoJUnitRunner.class) then MockitoAnnotations.initMocks(this); is not necessary (it may even cause issues when injecting), the mockito runner performs injection and additional stuffs to validate mocks.

Also having both mock init mechanisms may cause trouble with injection and stubbing, this is due to the way the lifecyle of JUnit test and how mockito unit-integration code is used :

1. The runner will create mocks and inject those mocks in the test object.
2. Then the @Before methods kicks in and recreate new mocks, and may not perform injection as the object is already initialized.