Spring controller testing with Mockito - spring

Question

I'm trying to test My Spring controllers using Mockito, but I can't actually get how can I do that without making everything #Mock.
Moreover test method returns me NullPointerException, as it can see no user and actually no user role at all.
Is there a way to test my controllers somehow?
(Controller class)
#Controller
#SessionAttributes("user")
#RequestMapping("/login.htm")
public class LoginController{
#Autowired
private UserDao userDao;
#Autowired
private LoginValidator loginValidator;
public LoginValidator getLoginValidator() {
return loginValidator;
}
public void setLoginValidator(LoginValidator loginValidator) {
this.loginValidator = loginValidator;
}
public UserDao getUserDao() {
return userDao;
}
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
#RequestMapping(method = RequestMethod.GET)
public String getSendEmptyForm(ModelMap model, HttpServletRequest req) {
req.getSession().invalidate();
model.addAttribute("loginForm", new LoginForm());
return "login";
}
#RequestMapping(method = RequestMethod.POST)
public String postSubmittedForm(ModelMap model, #ModelAttribute("loginForm") LoginForm loginForm,
BindingResult result, SessionStatus status) {
//validate form
loginValidator.validate(loginForm, result);
if (result.hasErrors()) {
return "login";
}
User user = userDao.findByLogin(loginForm.getLogin());
model.addAttribute("user", user);
if (user.getRole().getName().equals("Admin")) {
model.addAttribute("usersList", userDao.findAll());
return "viewAllUsersPage";
}
if (user.getRole().getName().equals("User")){
return "userPage";
}
model.addAttribute("error", "Your role is not User or Admin");
return "errorPage";
}
}
And my testing class
#RunWith(MockitoJUnitRunner.class)
public class LoginControllerTest {
#InjectMocks
private LoginController controllerUT = new LoginController();
#Mock
private ModelMap model;
#Mock
private LoginForm loginForm;
#Mock
private BindingResult result;
#Mock
private SessionStatus status;
#Mock
private LoginValidator validator;
#Mock
private UserDao userDao;
#Mock
private User useк;
#Test
public void testSendRedirect(){
final String target = "login";
String nextPage = controllerUT.postSubmittedForm(model, loginForm, result, status);
assertEquals(target, nextPage);
}
}

Answer 1

First off you seem to be missing stubbing for loginForm.getLogin() and userDao.findByLogin(loginForm.getLogin()) and user.getRole().getName(). Without such stubbing, these methods called on a mock will return a default value (i.e. null).
So you may want to add :
when(loginForm.getLogin()).thenReturn(login);
when(userDao.findByLogin(login)).thenReturn(user);
when(user.getRole()).thenReturn(role);
when(role.getName()).thenReturn("Admin");
You will want to vary the return values for different tests.
Depending on your implementation classes for User and Role, you could simply supply real instances.
For a test that simulates the result to have errors you'll want to add this stubbing :
when(result.hasErrors()).thenReturn(true);
since otherwise the default false is returned.