获取org.mockito.exceptions.misusing.PotentialStubbingProblem：使用restTemplate时严格存根参数不匹配

Question

我在应用程序中使用 RestTemplate 的 Exchange() 来调用外部 API。目前，我正在为restTemplate 调用编写junit 和mockito 测试用例，但我遇到了存根参数不匹配异常。

这是我的代码

@Service
public class ApiService {

  @Autowired
  private RestTemplate restTemplate;
  
  @Value("{url}")
  private String url;
  
  public TrackResponse getTpiValue(TrackRequest trackRequest){
  
    TrackResponse trackResponse = null;
    
    HttpHeaders headers = new HttpHeaders();
    
    HttpEntity<TrackRequest> entity = new HttpEntity<TrackRequest>(trackRequest, headers);
    
    ResponseEntity<TrackResponse> response = restTemplate.exchange(url, HttpMethod.Post, entity, TrackResponse.class);
    
    if(response.getStatusCode == HttpStatus.ok){
       trackResponse = response.getBody();
    }
  return trackResponse;
  }

}

这是我的测试用例

@TestInstance(Lifecycle.PER_CLASS)
@ExtendWith(MocikotExtension.class)
public class ApiServiceTest {

  @Mock
  private RestTemplate restTemplate;
  
  @InjectMocks
  private ApiService apiService;
    
  public void getTpiValueTest(){
  
    TrackRequest trackRequest = new TrackRequest();
    trackRequest.setId("UTHL10");
    
    TrackResponse trackResponse = new TrackResponse();
    trackResponse.setTrackId("QWEDRTHFDS");
    
    ResponseEntity<TrackResponse> response = new ResponseEntity<>(trackResponse, HttpStatus.ok);
    
    when(restTemplate.exchange(eq(null), eq(HttpMethod.Post), any(HttpEntity.class), eq(TrackResponse.class))).thenReturn(response);
    
    TrackResponse finalResponse = apiService.getTpiValue(trackRequest);
    
    assetEquals(response.getbody(), finalResponse.getTrackId());
  }

}

但是当我运行测试用例时，我遇到了以下错误

org.mockito.exceptions.misusing.PotentialStubbingProblem: 
Strict stubbing argument mismatch. Please check:
 - this invocation of 'exchange' method:
    restTemplate.exchange(
    null,
    POST,
    <com.application.track.TrackRequest@3c486eb1,[]>,
    class com.application.track.TrackResponse
);
    -> at com.application.track.ApiService.getTpiValue(ApiService.java:18)
 - has following stubbing(s) with different arguments:
    1. restTemplate.exchange(
    null,
    null,
    null,
    null
);
-> at com.application.track.ApiServiceTest.getTpiValueTest(ApiServiceTest.java:21)

我也尝试过 lenient() 但没有成功。

Answer 1

实际的方法调用是：

exchange(String url, HttpMethod method, HttpEntity<?> requestEntity, Class<T> responseType, Object... uriVariables)

但是现在当您将第一个参数存根为

NULL

时，编译器不知道它的类型。所以它认为你正在存根具有 4 个参数的方法，即：

exchange(URI url, HttpMethod method, HttpEntity<?> requestEntity, Class<T> responseType)

所以实际的方法调用永远不会被存根，它应该返回 NULL 或

UnnecessaryStubbingException

给我。不知道为什么你会得到

PotentialStubbingProblem

但...

无论如何，尝试更改为以下内容应该可以让您存根

ApiService

将正确调用的实际方法：

 when(restTemplate.exchange((String)eq(null), eq(HttpMethod.Post), any(HttpEntity.class), eq(TrackResponse.class))).thenReturn(response);

或者更好：

 when(restTemplate.exchange((String)isNull(), eq(HttpMethod.Post), any(HttpEntity.class), eq(TrackResponse.class))).thenReturn(response);