There was an unexpected error (type=Bad Request, status=400).以及@RequestBody和@RequestParam区别

今天在使用spring boot做设备微服务的开发时，报出了标题中的错误，完成的错误信息如下

Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.

Tue Feb 02 15:42:15 CST 2021
There was an unexpected error (type=Bad Request, status=400).

翻译最后一句为：发生意外错误（类型=错误的请求，状态= 400） ，如下贴出我的代码

    @RequestMapping(value = "/detail", method = RequestMethod.GET)
    public ResponseDto getDeviceDetail(
            @RequestHeader(name = Constant.HEADER_X_TRACE_ID, required = false) String traceId,
            @Validated @RequestBody DetailDeviceRequestBody requestBody,
            @PathVariable String requestPath,
            @PathVariable String requestCategory
    ) {
        。。。。。。
        String sn = requestBody.getSn();
        if ( isBlank(sn)) {
            return new ResponseDto(ErrorResponse.REQUEST_ERROR.getCode(),ErrorResponse.REQUEST_ERROR.getMessage());
        }
        。。。
        return iDeviceService.getDeviceDetail(deviceEntity);
    }

问题出现在这里 @Validated @RequestBody DetailDeviceRequestBody requestBody,，我明明是get请求，却使用@RequestBody去接收数据，然而get请求是没有请求体的，因为报出了这样的，我们可以使用@RequestParam来接收，如下代码所示

   @RequestMapping(value = "/detail", method = RequestMethod.GET)
    public ResponseDto getDeviceDetail(
            @RequestHeader(name = Constant.HEADER_X_TRACE_ID, required = false) String traceId,      
            @RequestParam(required = false) String sn,
            @PathVariable String requestPath,
            @PathVariable String requestCategory
    ) {
        if ( isBlank(sn)) {
            return new ResponseDto(ErrorResponse.REQUEST_ERROR.getCode(),ErrorResponse.REQUEST_ERROR.getMessage());
        }
        。。。
        return iDeviceService.getDeviceDetail(deviceEntity);
    }

这样就能轻松地接收get的请求值了。

下面链接是说明@RequestBody和@RequestParam区别：@RequestBody和@RequestParam区别