How to inject mock in parent class with Mockito?

Question

I'm using mockito to mock my services..

How can I inject mocks in parent class?

Sample:

public abstract class Parent(){

    @Mock
    Message message;

}

public class MyTest() extends Parent{

    @InjectMocks
    MyService myService //MyService has an instance of Message

    //When I put @Mock Message here it works
}

When I run my tests the message in Parent stay null

mocks can be injected via constructor. if doing DI then architecture the classes to get dependencies via constructor injection — Nkosi, Nov 10 '16 at 12:47

score 4 · Accepted Answer · edited Jan 12 '18 at 16:47

Two ways to solve this:

1) You need to use MockitoAnnotations.initMocks(this) in the @Before method in your parent class.

The following works for me:

public abstract class Parent {
    @Mock
    Message message;

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

public class MyTest extends Parent {
    @InjectMocks
    MyService myService = new MyService(); //MyService has an instance of Message
    ...
}

2) If want to use the @RunWith(MockitoJUnitRunner.class) above the class definition, then this must be done in the Parent class:

@RunWith(MockitoJUnitRunner.class)
public class Parent {
...

Note that declaring the @Mock in both the Parent and MyTest class will cause the injected object to be null. So you will have to pick where you want to declare this.

How to inject mock in parent class with Mockito?

1 Answers1