我想為我的UserController班級(jí)編寫一個(gè) JUnit 測試（Java 單元），但我不知道該怎么做。用戶控制器：@RestController@RequestMapping(CompositeController.ENTRY)public class UserController {protected final static String ENTRY = "/demo/v1/composite";private UserService userService;@Autowiredpublic UserController(UserService userService) {    this.userService = userService;} @GetMapping(path = "/isadmin") public ResponseEntity<Boolean> checkadmin(@RequestHeader String nickname){ return userService.checkifadmin(nickname); }用戶服務(wù)：import org.springframework.http.ResponseEntity;import org.springframework.stereotype.Service;@Servicepublic interface UserService {ResponseEntity<Boolean> checkifadmin(String nickname);}UserServiceImpl:public class UserServiceImpl implements UserService { private final String userBaseAdress = "http://localhost:7777"; private final String userBasePath = "/demo/v1/user"; public ResponseEntity<Boolean> checkifadmin(String nickname) {                  HttpHeaders headers = new HttpHeaders();                    headers.setContentType(MediaType.APPLICATION_JSON);        headers.set("nickname", nickname);               HttpEntity<String> entity = new HttpEntity<String>(headers);                     RestTemplate restTemplate = new RestTemplate();                  ResponseEntity<Boolean> response = restTemplate.exchange(userBaseAdress + userBasePath + "/isadmin",                HttpMethod.GET, entity, Boolean.class);                 return response;    }}