org.mockito
Annotation Type Mock

@Target(value=FIELD)
@Retention(value=RUNTIME)
public @interface Mock

• Allows shorthand mock creation.
• Minimizes repetitive mock creation code.
• Makes the test class more readable.
• Makes the verification error easier to read because the field name is used to identify the mock.

   public class ArticleManagerTest extends SampleBaseTestCase { 
     
       @Mock private ArticleCalculator calculator;
       @Mock private ArticleDatabase database;
       @Mock private UserProvider userProvider;
     
       private ArticleManager manager;
     
       @Before public void setup() {
           manager = new ArticleManager(userProvider, database, calculator);
       }
   }
   
   public class SampleBaseTestCase {
   
       @Before public void initMocks() {
           MockitoAnnotations.initMocks(this);
       }
   }
 

MockitoAnnotations.initMocks(this) method has to called to initialize annotated mocks.

In above example, initMocks() is called in @Before (JUnit4) method of test's base class. For JUnit3 initMocks() can go to setup() method of a base class. You can also put initMocks() in your JUnit runner (@RunWith) or use built-in runners: MockitoJUnit44Runner, MockitoJUnitRunner