[FIXED] How to test JWT expiration in Spring REST?

Issue

I want to write a unit test for checking expiration of JWT. I used Mockito.spy to throw an exception, but not works. So far, here is my progress:

@Test
public void hello_fail_expired_token() throws Exception {
    User user = FakeDataGenerator.generateFakeUser();
    User registeredUser = userService.register(user.getEmail(), user.getPassword(), user.getName());
    String token = jwtService.generateToken(registeredUser);
    Mockito.doThrow(new JWTExpiredException()).when(Mockito.spy(jwtService)).verifyToken(token);
    MockHttpServletRequestBuilder mockRequest = MockMvcRequestBuilders.get("/user/hello")
            .contentType(MediaType.APPLICATION_JSON)
            .accept(MediaType.APPLICATION_JSON)
            .header("Authorization", "Bearer " + token);
    System.out.println(mockMvc.perform(mockRequest).andReturn().getResponse().getContentAsString());
}

After the execution of this method, no exception is throwed. What is my fault?

Solution

I figured out. Before:

@Autowired
JWTService jwtService;

Now:

@Spy
JWTService jwtService;

And in test method, before:

Mockito.doThrow(new JWTExpiredException()).when(Mockito.spy(jwtService)).verifyToken(token);

After:

Mockito.doThrow(new JWTExpiredException()).when(jwtService).verifyToken(token);

Answered By - Jan Franco