Login page Junit test with mockito

Question

I guess this is simple problem, but I am unable to get my head around it. this is the class for which I need to write test case

@Controller
@SessionAttributes
public class LoginController {


@RequestMapping(value = "/Login", method = RequestMethod.GET)
public ModelAndView displayLogin(@RequestParam(value = "error", required = false) String error,
                                 @RequestParam(value = "logout", required = false) String logout,
                                 HttpServletRequest request,
                                 HttpServletResponse response) {

    ModelAndView modelForLogin = new ModelAndView();

    if (error != null) {

        // Include login failure message
        modelForLogin.addObject("loginFailure", "Invalid username and password!");

    }

    if ("user".equals(logout)) {

        // Include logout message
        modelForLogin.addObject("msg", "You've been logged out successfully.");
    }

    else {

        modelForLogin.addObject("msg","");
    }


    modelForLogin.setViewName("Login");

    return modelForLogin;

}

}

This is what I have got till now...

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@ContextConfiguration({ " servlet-xml "})

public class LoginControllerTest {


@Mock HttpServletRequest request;
@Mock HttpServletResponse response;
@Mock HttpSession session;


private MockMvc mockMvc;

@Before
 protected void setUp() throws Exception {
   MockitoAnnotations.initMocks(this);
   ModelAndView modelForLogin = mockito.mock(ModelAndView.class);
   mockito.when(modelForLogin.error()).thenReturn("error");
   mockito.when(modelForLogin.logout()).thenReturn("logout");

 }

@Test
public void TestLoginError() throws Exception {

    mockMvc.perform(get("/Login").param()).andExpect(status().isOk()).andExpect(model().attributeExists("msg"));


}



@Test
public void testLogin() throws Exception {

    mockMvc.perform(get("/Login")).andExpect(status().isOk());
    mockMvc.perform(get("/Login").param("logout", "log")).andExpect(status().isOk()).andExpect(model().attributeExists("msg"));
    mockMvc.perform(get("/Login").param("error", "log")).andExpect(status().isOk()).andExpect(model().attributeExists("error"));
    mockMvc.perform(get("/Login").param("logout", "log").param("error", "log")).andExpect(status().isOk()).andExpect(model().attributeExists("msg")).andExpect(model().attributeExists("error"));
    mockMvc.perform(get("/Login")).andExpect(status().isOk()).andExpect(view().name("login"));
}

}

Can anyone please let me know proper way to write test case for this?

Solution

Given the code you have, there is no need to mock. A sample test case would look like below:

ModelAndView mvw =  displayLogin("error", null, null, null);
assertEquals("Invalid username and password!", mvw.getModelMap().get("loginFailure"));