flo8433 flo8433 - 9 days ago 3
Java Question

Mockito mock objects returns null

Hey i try to implement some tests for my jsf application and for the mocks i am using mockito. (I also use spring)

@RunWith(MockitoJUnitRunner.class)
public class GeneralConfigServiceImplTest {

private GeneralConfigService generalConfigService;

@Mock
private GeneralConfigDAO generalConfigDAO;

@Mock
private GeneralConfig gen;

@Before
public void setUp() {
MockitoAnnotations.initMocks(this);
generalConfigService = new GeneralConfigService();
ReflectionTestUtils.setField(generalConfigService, "generalConfigDAO", generalConfigDAO);
}

@Test
public void testAddGeneralConfigCallDAOSuccess() throws DAOException, EntityNullException, IllegalEntityArgumentException, ParseException, EntityPersistException {
gen = createGeneralConfigs("label", "value");

generalConfigService.setInstance(gen);
generalConfigService.persist();
log.info(generalConfigService.getInstance().toString());
}
}


The test succeeds, but when I want to retrieve the instance with the
getInstance
method. All Parameters which I have set before (via the constructor before) are null.
I am new to mocked objects, so is this behavior normal, or is there a mistake in my code?

Answer

It really depends on GeneralConfigService#getInstance() implementation. Also you can simplify your test code a lot if you use @InjectMocks annotation.

When using MockitoJUnitRunner you don't need to initialize mocks and inject your dependencies manually:

@RunWith(MockitoJUnitRunner.class)
public class GeneralConfigServiceImplTest  {

    @InjectMocks
    private GeneralConfigService generalConfigService;

    @Mock
    private GeneralConfigDAO generalConfigDAO;

    @Test
    public void testAddGeneralConfigCallDAOSuccess() {
       // generalConfigService is already instantiated and populated with dependencies here
       ...
    }
}