[FIXED] Spring Boot - Mockito: Unfinished Stubbing detected

Issue

I am new to JUnit and Mockito. Can someone please guide how to mock the below rest template? My current mocking shows an error: Unfinished Stubbing.

Service

class MyService {

   void func(){
       (SimpleClientHttpRequestFactory).restTemplate.getRequestFactory()).setConnectTimeout(t1);
   }
}

Mockito

Class MyTest {
    @Inject
    MyService service;
    
    @Mock
    RestTemplate template;

    @Test
    void testit(){    
        doNothing().when((SimpleClientHttpRequestFactory)
                   .restTemplate.getRequestFactory())).setTimeout(anyInt();
    }
}

Solution

You need to add initMocks() or openMocks() for mock initialisation like that:

@BeforeEach(for Junit5 @Before for Junit4)
void setUp(){
   initMocks(this);
}

And then you should declare your mocks behavior in the "when-then" section:

when(restTemplate.getRequestFactory()).thenReturn(mock(RequestFactory.class));

Use mockito for stubbing chain of invocation your methods.

Full version example:

Class MyTest {
    @Inject
    MyService service;
    
    @Mock
    RestTemplate template;

    @BeforeEach
    void setUp(){
       initMocks(this);
    }

@Test
void testit(){
   RestTemplate template = mock(RestTemplate.class);
   ClientHttpRequestFactory factory = mock(ClientHttpRequestFactory.class);

   when(restTemplate.getRequestFactory()).thenReturn(template));
   when(template.getRequestFactory).thenReturn(factory);
   etc...
   
}

}

Answered By - Dmitrii Bykov
Answer Checked By - Pedro (JavaFixing Volunteer)