在Spring Boot中無法從REST API返回錯誤代碼和消息

Question

我是Spring Boot的新手。 我已經在Spring Boot中實現了以下rest api：

 @GetMapping(value = "/output")
 public ResponseEntity<?> getListOfPOWithItem(@QueryParam("input1") String input1,
                                        @QueryParam("input2") String input2)
                                   throws  BusinessException {
 if (input1 == null) {
  throw new BusinessException("Query param input1 is null or invalid");
 }
 if (input2 == null) {
  throw new BusinessException("Query param input2 is null or invalid");
 }


 List<Output> outputList = 

   myService.getDetails(input1, input2);

   if (outputList != null) {
       return new ResponseEntity<List<Ouput>>(outputList, HttpStatus.OK);
   }
   return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
 }

Myservice中的getDetails（）定義如下：

public List<Output> getDetails(String input1, String input2)
      throws BusinessException {
String path = new StringBuilder().append(getBaseUrl()).append("/input1/")
        .append(input1).append("/input2/").append(input2).toString();
try {
  ResponseEntity<List<Output>> responseEntityList = restTemplate.exchange(path,
          HttpMethod.GET, null, new ParameterizedTypeReference<List<Output>>() {});
  List<Output> outputList = responseEntity.getBody();

  if (responseEntityList.isEmpty()) {
    throw new EntityNotFoundException("Input not found",
        ExternalServicesErrorCode.NO_DATA_FOUND);
  }
  return outputList;

} catch (HttpStatusCodeException e) {
  int statusCode = e.getStatusCode().value();

  if (statusCode == Status.NOT_FOUND.getStatusCode()) {
    throw new EntityNotFoundException("Data not found",
        ExternalServicesErrorCode.NO_DATA_FOUND);

  } else {
    throw new BusinessException("Error in getting data", ExternalServicesErrorCode.SERVICE_ERROR);
  }
}

}

問題是：調用此API進行無效輸入時，我得到500，而不是404和錯誤消息“找不到數據”。 誰能建議我在上面的代碼中進行哪些更改？

編輯：按照建議，我添加了以下課程：

@RestControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {

 @ExceptionHandler(Exception.class)
 public final ResponseEntity<ExceptionResponse> 
  handleAllExceptions(Exception ex,
  WebRequest request) {

 ExceptionResponse exceptionResponse = new ExceptionResponse(Instant.now().toEpochMilli(),
    ex.getMessage(), request.getDescription(true));
  return new ResponseEntity<>(exceptionResponse, HttpStatus.INTERNAL_SERVER_ERROR);
 }

@ExceptionHandler(EntityNotFoundException.class)
 public final ResponseEntity<ExceptionResponse> handleEntityNotFoundException(
  EntityNotFoundException ex, WebRequest request) {

   ExceptionResponse exceptionResponse = new ExceptionResponse(Instant.now().toEpochMilli(),
    ex.getMessage(), request.getDescription(true));
   return new ResponseEntity<>(exceptionResponse, HttpStatus.NO_CONTENT);
}

即使在那之后，我也無法按預期獲得錯誤代碼和錯誤消息。

Answer 1

根據您的控制器，它用於引發“ BusinessException”異常。 但是您尚未實現在Controller Advisor中捕獲該異常的方法“ GlobalExceptionHandler”。 測試成功后，請在您的控制器顧問中包括以下方法。

    @ExceptionHandler(BusinessException.class)
    public ResponseEntity<String> handleBusinessException(BusinessException businessException ) {

        return new ResponseEntity<>("Your specific error", HttpStatus.NOT_FOUND);
    }

以下是測試結果

Answer 2

您遇到的異常處理代碼缺失，請參閱https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/web/servlet/mvc/method/annotation/ResponseEntityExceptionHandler.html和https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/bind/annotation/ExceptionHandler.html

Answer 3

如果兩個輸入都是無效錯誤消息，則應該創建組合消息，而不是引發業務異常，然后可以返回responseEntity作為快速解決方案：
返回新的ResponseEntity <>（“ Invalid input”，HttpStatus.NOT_FOUND）;

Answer 4

要通過@RestControllerAdvice處理此修復程序，您應該創建一個自定義異常，其中包含httpStatus代碼和您要返回的消息

public class CustomBusinessException extends Exception{

/**
 * 
 */
private static final long serialVersionUID = 1L;

private final String status;
private final String requestMessage;
private final String description;


    public CustomBusinessException (Throwable ex,String status, String requestMessage, String description) {
    super(ex);
    this.status = status;
    this.requestMessage = requestMessage;
    this.description = description;
}
//create getter and setter

}

通過您的自定義異常處理程序（@RestCOntrollerAdvice）處理此異常，並准備要像這樣發送的自定義響應

@ExceptionHandler({ CustomBusinessException .class })
public ResponseEntity<CustomBusinessResponse> handleAll(CustomBusinessException customBusinessException , WebRequest request) {

    logger.error("Exception occured in NRACustomExceptionHandler :"+ExceptionUtils.getStackTrace(nraGatewayException));
    CustomBusinessResponse response = new CustomBusinessResponse();
    response.setMessage(customBusinessException.getRequestMessage());
    response.setDescription(customBusinessException.getDescription());

    return new ResponseEntity<>(response, new HttpHeaders(), HttpStatus.valueOf(Integer.parseInt(customBusinessException.getStatus())));
}

創建一個自定義響應類

public class NRAExceptionResponse {

private String message;

private String description;


//create getter and setter
}

拋出具有這樣發送狀態的自定義異常

  throw new NRAGatewayException(e, "404","Invalid Input", "Invalid input 1 and input 2");