关于传参为HttpServletRequest request时，如何转为对应的实体类数据，且进行注解非空判断等@Validated。可通过Validator进行实体类的注解判断。

以你之姓@ 2023-10-10 15:03 2阅读 0赞

**首先，该需求就是前端穿过来的数据为HttpServletRequest类时，就不能进行@Validated判断了，所以，想对其进行判断得分二步，**

**其一，先将其转化为对应的实体类，**

**其二，通validator.validate（）对其进行实体类中的注解判断。**

代码：

public AjaxResult submit(HttpServletRequest request)
        {
            //此为将request转为String类，再将其转为实体类。
            String body = DataConvertUtil.getRequestBody(request);
            OkbApplyInfo okbApplyInfo = JSONUtil.toBean(body, OkbApplyInfo.class);
    
            //这里是进行注解判断
            ValidatorFactory vf = Validation.buildDefaultValidatorFactory();
            Validator validator = vf.getValidator();
            //若有不通过的属性值则存入set中
            Set<ConstraintViolation<OkbApplyInfo>> set = validator.validate(okbApplyInfo);
            if(set.size() > 0) {
                for (ConstraintViolation<OkbApplyInfo> constraintViolation : set) {
                    return AjaxResult.error(constraintViolation.getMessage());
                }
            }
    }

**其中有一个getRequestBody方法将request转为string类型。**

/**
         *  request转string
         * @param request
         * @return
         */
        public static String getRequestBody(HttpServletRequest request) {
            StringBuilder builder = new StringBuilder();
            InputStream inputStream = null;
            try {
                inputStream = request.getInputStream();
                byte[] bytes = new byte[4096];
                for(int n; (n=inputStream.read(bytes)) != -1;) {
                    builder.append(new String(bytes, 0, n));
                }
            }
            catch (IOException e) {
                e.printStackTrace();
            }
            finally {
                if(inputStream != null) {
                    try {
                        inputStream.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
            return builder.toString();
        }