Object reference changing during Mockito Test - spring

Question

I have just started working with Mockito and am having a problem with one of the tests failing, yet the actual code works correctly in a live environment. The controller being tested is:
#Controller
#RequestMapping("/notes")
public class NotesController {
private NoteRepository noteRepository;
private MyUserRepository userRepository;
#RequestMapping(value = "/add", method = POST)
public String postNote(#Valid Note note, BindingResult errors, Principal principal){
String username = principal.getName();
MyUser user = userRepository.findUserByUsername(username);
note.setMyUser(user);
note.setTime(new Date());
noteRepository.save(note);
return "redirect:/notes"; }
}
The test is here:
#Test
public void testShouldAddValidNote() throws Exception {
MyUser testing = new MyUser();
Note note = new Note();
NoteRepository noteRepository = mock(NoteRepository.class);
when(noteRepository.save(note)).thenReturn(note);
MyUserRepository userRepository = mock(MyUserRepository.class);
when(userRepository.findUserByUsername("testing")).thenReturn(testing);
Principal mockPrincipal = mock(Principal.class);
when(mockPrincipal.getName()).thenReturn("testing");
NoteController controller = new NoteController(noteRepository);
controller.setMyUserRepository(userRepository);
MockMvc mockMvc = standaloneSetup(controller).build();
mockMvc.perform(post("/notes/add")
.requestAttr("note", note)
.principal(mockPrincipal))
.andExpect(view().name("redirect:/notes"));
verify(noteRepository,times(1)).save(note);
verify(note,times(1)).setMyUser(testing);
verify(note,times(1)).setTime((Date)anyObject());
verify(userRepository,times(1)).findUserByUsername("testing");
verify(mockPrincipal,times(1)).getName();
}
The first verify test fails, with the message:
Argument(s) are different! Wanted:
noteRepository.save(projectName.Note#5ae9);
Actual invocation has different arguments:
noteRepository.save(projectName.Note#c079ae45
Clearly the Note object passed in to the method has changed, but I thought that using .requestAttr("note", note) would pass in the reference and the same object should therefore be in the method (and later returned). Like I said, it works perfectly in the live web Container, so what am I getting wrong with the Mockito test please?

Answer 1

This is just a wild guess could the issue this code faces comes from MockMvc / MockMvcRequestBuilders where the Note is somehow serialized / deserialized between the request configuration and the actual request ?
Note that note is a real object so calling verify(note).... won't work.
Anyway I suggest the use of the combination of a mockito captor and AssertJ in this case :
// if field instantiation if using the mockito runner / rule or MockitoAnnotations.initMocks(this)
#Captor ArgumentCaptor<Note> noteCaptor;
// if created in the test method
ArgumentCaptor<Note> noteCaptor = ArgumentCaptor.forClass(Note.class);
// ...
verify(noteRepository,times(1)).save(noteCaptor.capture());
assertThat(noteCaptor.getValue().geMyUser()).isEqualTo(testing);
assertThat(noteCaptor.getValue().geTime()).isCloseTo(someDate);
Note I'm on a phone