why my unit test for my rest controller method with mock doesn't work? - spring-boot

Question

I try to make a dummy test of a method in my controller but doesn't work , i have a null pointer exception and i would like to know why it doesn't work, i precise that's my first time when i make this kind of tests.
This is my rest controller :
#RestController
#RequestMapping("/api")
public class AdminController {
#Autowired
private UserService userService;
#Secured(value = "ROLE_ADMIN")
#GetMapping("/roles")
public ResponseEntity<List<Role>> getRoles(){
return new ResponseEntity(userService.getRoles(), HttpStatus.OK);
}
This my controller test :
#RunWith(SpringRunner.class)
#WebMvcTest(value = AdminController.class, secure = false)
public class AdminControllerTest {
private MockMvc mvc;
#MockBean
UserService userService;
#Test
public void getRoles() throws Exception{
Role role=new Role("Admin");
List<Role> roles=Arrays.asList(role);
given(userService.getRoles()).willReturn(roles);
mvc.perform(get("/api/roles")).andExpect(status().isOk());
}
When i run the test for this method a i have this kind of error :
Thank you in advance for your help

Answer 1

Try this. It should work. I think you missed #Autowired annotation
#RunWith(SpringRunner.class)
#WebMvcTest(value = AdminController.class, secure = false)
public class AdminControllerTest {
#Autowired
private MockMvc mvc;
#MockBean
UserService userService;
#Test
public void getRoles() throws Exception{
Role role=new Role("Admin");
List<Role> roles=Arrays.asList(role);
given(userService.getRoles()).willReturn(roles);
mvc.perform(get("/api/roles")).andExpect(status().isOk());
}
}