Using @Mock and @InjectMocks

Question

I'm currently studying the Mockito framework and I've created several test cases using Mockito. But then I read that instead of invoking mock(SomeClass.class) I can use the @Mock and the @InjectMocks - The only thing I need to do is to annotate my test class with @RunWith(MockitoJUnitRunner.class) or use the MockitoAnnotations.initMocks(this); in the @Before method.

But it doesn't work - It seems that the @Mock won't work! Here is my 2 codes revisions - one using the annotations and one without.

What am I doing wrong?

public class ReportServiceImplTestMockito {      private TaskService       mockTaskService; // This is the Mock object     private ReportServiceImpl service;      @Before     public void init(){         service         = new ReportServiceImpl();         mockTaskService = mock(TaskServiceImpl.class);         service.setTaskServiceImpl(mockTaskService);     } /// ...   Some tests } 

As I said - this work great. But the following wont:

@RunWith(MockitoJUnitRunner.class) public class ReportServiceImplTestMockito {       @Mock       private TaskService      mockTaskService;       @InjectMocks       private ReportServiceImpl service;           // Some tests } 

And here is the ReportServiceImpl class:

@Service public class ReportServiceImpl implements ReportService {      @Autowired     private TaskService taskServiceImpl;      public ReportServiceImpl(){}      public ReportServiceImpl(TaskService taskService){         this.taskServiceImpl = taskService;     }      public void setTaskServiceImpl(TaskService taskServiceImpl) {         this.taskServiceImpl = taskServiceImpl;     } } 

What am I missing?

Answer 1

O.K, I got my mistake!!! I've used the @InjectMocks but initialized the same variable in the init() method... So what happened was that mockito injected the mock objects to my variable - but seconds later I ran it over - initializing that very same variable!!!

Answer 2

Your code works fine for me using Mockito 1.9.

Using an 1.8+ version of Mockito I get a very specific error message telling me exactly how to fix the problem. As php-coder suggests: For Mockito 1.8+ you need to initialize the field.

Did you see this or any other error message?

Edit:

The following code works for me. Small changes:

• Removed Spring annotations
• Removed Interface
• Added Getter
• Added empty TaskService
• Added test with System.out.println

Does it produce an error for you? :

Service:

public class ReportServiceImpl {      private TaskService taskServiceImpl;       public ReportServiceImpl() {      }       public ReportServiceImpl(TaskService taskService) {         this.taskServiceImpl = taskService;     }       public void setTaskServiceImpl(TaskService taskServiceImpl) {         this.taskServiceImpl = taskServiceImpl;     }       public TaskService getTaskServiceImpl() {         return taskServiceImpl;     } } 

Dependency:

public class TaskService {  } 

Test, prints mockTaskService:

@RunWith(MockitoJUnitRunner.class) public class ReportServiceImplTestMockito {      @Mock     private TaskService       mockTaskService;      @InjectMocks     private ReportServiceImpl service;       @Test     public void testMockInjected() {         System.out.println(service.getTaskServiceImpl());     } }