Spring MVC 学习之 400 错误

如果一个方法中有参数被 @Valid 标注了，但该参数后面没有紧跟一个 BindingResult 类型的参数，那么提交到该方法时，将返回 400 错误。

错误消息将会是：The request sent by the client was syntactically incorrect ().

错误的方法定义 1 ：（错误原因：没有 BindingResult 参数）

@RequestMapping ({ "error400"  })  public  String error400( @Valid  @ModelAttribute ( "testForm" ) TestForm testForm) {       return "test" ;  }

错误的方法定义 2 ：（错误原因：没有紧跟在 @Valid 参数之后）

@RequestMapping ({ "error400"  }) public  String error400( @Valid  @ModelAttribute ( "testForm" ) TestForm testForm, Model model, Errors result) {      return "demo/front/test" ; }

也可参考 DefaultHandlerExceptionResolver.java 中的方法说明：

/**    * Handle the case where an {@linkplain ModelAttribute @ModelAttribute} method    * argument has binding or validation errors and is not followed by another    * method argument of type {@link BindingResult}.    * By default an HTTP 400 error is sent back to the client.    * @param request current HTTP request    * @param response current HTTP response    * @param handler the executed handler    * @return an empty ModelAndView indicating the exception was handled    * @throws IOException potentially thrown from response.sendError()    */ protected ModelAndView handleBindException(BindException ex, HttpServletRequest request,           HttpServletResponse response, Object handler) throws  IOException {       response.sendError(HttpServletResponse.SC_BAD_REQUEST);       return new  ModelAndView();  }

转载于:https://www.cnblogs.com/scwanglijun/p/3893980.html