Bean Validation设置校验失败全局返回信息(续自定义JSR validation)

青旅半醒 2022-06-09 08:54 194阅读 0赞

demo网址在上一篇有，这篇写如何定义validation验证失败后的返回信息。

![Center][](截图源于上篇)

由下图看出验证失败后Swagger会抛出一堆错误信息，但其实前端要的只是错误的字段信息，即一般我们只需返回错误字段的信息，下面为上红框异常类的源码:

public class MethodArgumentNotValidException extends Exception {
        private final MethodParameter parameter;
        private final BindingResult bindingResult;
    
        public MethodArgumentNotValidException(MethodParameter parameter, BindingResult bindingResult) {
            this.parameter = parameter;
            this.bindingResult = bindingResult;
        }
    
        public MethodParameter getParameter() {
            return this.parameter;
        }
    
        public BindingResult getBindingResult() {
            return this.bindingResult;
        }
    
        public String getMessage() {
            StringBuilder sb = (new StringBuilder("Validation failed for argument at index ")).append(this.parameter.getParameterIndex()).append(" in method: ").append(this.parameter.getMethod().toGenericString()).append(", with ").append(this.bindingResult.getErrorCount()).append(" error(s): ");
            Iterator var2 = this.bindingResult.getAllErrors().iterator();
    
            while(var2.hasNext()) {
                ObjectError error = (ObjectError)var2.next();
                sb.append("[").append(error).append("] ");
            }
    
            return sb.toString();
        }
    }

从源码可以看出验证失败Swagger输出的信息都是该异常类组装的字符串，若要自定义返回信息，那我们只需从这个异常类获取相应的信息根据需要组装返回即可。由于验证失败会抛出异常，所以我们可以通过设置全局异常同一处理，具体处理类如下：

@ControllerAdvice
    @ResponseBody//必须添加，否则Spring会将返回值当作视图解析抛出异常
    public class ParamExceptionHandler {
        @Autowired
        private HttpServletRequest request;
    
        @ExceptionHandler(value = MethodArgumentNotValidException.class)
        public Object MethodArgumentNotValidHandler(MethodArgumentNotValidException exception){
            //按需重新封装需要返回的错误信息
            List<ParamValidationResult> paramValidationResults = new ArrayList<>();
            //解析原错误信息，封装后返回，此处返回非法的字段名称，错误信息
            for (FieldError error : exception.getBindingResult().getFieldErrors()) {
                ParamValidationResult validationResult = new ParamValidationResult();
                validationResult.setMessage(error.getDefaultMessage());
                validationResult.setParam(error.getField());
                paramValidationResults.add(validationResult);
            }
            return new ResultMsg(ResultCode.CODE_401, paramValidationResults);
        }
    }

个人自定义返回码：

public enum ResultCode {
        CODE_200(200, "访问成功"),
        CODE_401(401, "非法请求，参数错误"),
        CODE_402(402, "未授权，accessToken过期或无效"),
        CODE_403(403, "Method使用错误，请查看API"),
        CODE_404(404, "找不到访问地址"),
        CODE_406(406, "没有权限访问"),
        CODE_500(500, "系统内部错误"),
        CODE_501(501, "对象已存在，请检测唯一性"),
        CODE_502(502, "当前版本与服务器版本不一致,请更新应用"),
        CODE_503(503, "对象不存在，请检测请求参数"),
        CODE_504(504, "服务器连接错误，请稍后重试"),
        CODE_505(505, "key校验失败"),
        CODE_506(506, "RPC服务连接失败，请稍后重试");
    
        public Integer code;
        public String msg;
    
        ResultCode(Integer code, String msg) {
            this.msg = msg;
            this.code = code;
        }
    }

返回信息类：

public class ResultMsg {
        private Integer code;
        private String msg;
        private Object data;
    
        public ResultMsg() {
        }
    
        public ResultMsg(ResultCode resultCode) {
            this.code = resultCode.code;
            this.msg = resultCode.msg;
        }
    
         public ResultMsg(ResultCode resultCode,Object data) {
             this.code = resultCode.code;
             this.msg = resultCode.msg;
             this.data = data;
        }
    
        public Object getData() {
            return data;
        }
    
        public void setData(Object data) {
            this.data = data;
        }
    
        public Integer getCode() {
            return code;
        }
    
        public void setCode(Integer code) {
            this.code = code;
        }
    
        public String getMsg() {
            return msg;
        }
    
        public void setMsg(String msg) {
            this.msg = msg;
        }
    }

再次运行测试Swagger已能输出理想的错误信息

![Center 1][]

[Center]: /images/20220609/5da7167535424a1e97988e1fb95db086.png
[Center 1]: /images/20220609/de436b67ce324665b0d0860a9a3ee9f6.png