使用注解验证参数，并注册全局异常拦截器

我会带着你远行 2023-07-12 14:15 15阅读 0赞

**首先，这是一个spingboot工程，springboot默认内置了hibernate-validator验证包，如下图所示：**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA_size_16_color_FFFFFF_t_70]  
**我们需要对student类中的字段进行验证，hibernate-validator常用注解请参考以下链接**

> https://blog.csdn.net/dh554112075/article/details/80790464

**我们定义Student类，get、set方法省略**

@Min(value = 20,message = "最小值为20")
        @Max(value = 100,message = "最大值为100")
        @NotNull(message = "年龄不能为空")
        private Integer age;
    
        @NotBlank(message = "名字不能为空")
        private String name;
    
        @Length(max = 3,min = 3,message = "号码必须要3位")
        private String number;

**在controller中使用@Valid表示我要对这个对象进行参数校验**

@GetMapping("/addStudent")
        public Object addStudent(@Valid Student student){ 
            return "success";
        }

**其实到这已经成功，但是参数校验失败的校验信息不好看，所以我们自定义一个全局异常拦截器**

*  @ControllerAdvice可以拦截所有加@RequestMapping的方法
 *  @ExceptionHandler表示处理那种类型的异常

@ControllerAdvice
    public class GlobalExceptionInterceptor { 
    
        @ExceptionHandler(value = Exception.class)
        @ResponseBody
        public Object exceptionHander(HttpServletRequest request,Exception e){ 
            List returnlist = new ArrayList();
            if(e instanceof BindException){ 
                Iterator<FieldError> iterator = ((BindException) e).getBindingResult().getFieldErrors().iterator();
                while (iterator.hasNext()){ 
                    FieldError fieldError = iterator.next();
                    String errorMsg = fieldError.getDefaultMessage();
                    returnlist.add(errorMsg);
                }
            }
            return returnlist;
        }
    
    }

**使用postman进行测试**  
![测试结果][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA_size_16_color_FFFFFF_t_70 1]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200308221205802.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20200308222622900.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3ptOTg5OA==,size_16,color_FFFFFF,t_70