SpringRest处理空请求体（400个错误请求）

Question

我正在使用Spring4开发一个RESTful应用程序。我想处理当一个POST请求不包含正文时的情况。我编写了以下自定义异常处理程序：

    @ControllerAdvice
    public class MyRestExceptionHandler {
     
      @ExceptionHandler
      @ResponseStatus(HttpStatus.BAD_REQUEST)
      public ResponseEntity<MyErrorResponse> handleJsonMappingException(JsonMappingException ex) {
          MyErrorResponse errorResponse = new MyErrorResponse("request has empty body");
          return new ResponseEntity<MyErrorResponse>(errorResponse, HttpStatus.BAD_REQUEST);
      }   
      @ExceptionHandler(Throwable.class)
      public ResponseEntity<MyErrorResponse> handleDefaultException(Throwable ex) {
        MyErrorResponse errorResponse = new MyErrorResponse(ex);
        return new ResponseEntity<MyErrorResponse>(errorResponse, HttpStatus.BAD_REQUEST);
      }
    }
    
     @RestController
     public class ContactRestController{
        @RequestMapping(path="/contact", method=RequestMethod.POST)
        public void save(@RequestBody ContactDTO contactDto) {...}
     } 

当它收到一个没有正文的POST时，这些方法不会被调用。相反，客户端得到一个带有400个坏请求HTTP状态和空正文的响应。有人知道怎么处理吗？

Answer 1

我解决了这个问题（自定义异常处理程序必须扩展ResponseEntityExceptionHandler)。我的解决方案如下：

        @ControllerAdvice
        public class RestExceptionHandler extends ResponseEntityExceptionHandler {
    
            @Override
            protected ResponseEntity<Object> handleHttpMessageNotReadable(
                HttpMessageNotReadableException ex, HttpHeaders headers,
                HttpStatus status, WebRequest request) {
                // paste custom hadling here
            }
        }