SpringBoot实战篇之接口参数校验和全局异常处理前言对接口请求参数校验是每一个开发人员都必须熟知且善用的功能，是

前言对接口请求参数校验是每一个开发人员都必须熟知且善用的功能，是保证程序健壮性的基石。

除引入方式不同，使用方式和SpringMvc基本一致。

一、参数校验

引入库 org.springframework.boot spring-boot-starter-validation

全局异常处理 package org.example.springboot3.config;

import jakarta.validation.ConstraintViolationException; import org.example.springboot3.bigevent.entity.Result; import org.springframework.util.StringUtils; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.RestControllerAdvice;

/**

Create by sean on 2024/6/14 */ @RestControllerAdvice public class GlobalExceptionHandler { @ExceptionHandler(ConstraintViolationException.class) public Result exceptionHadler(ConstraintViolationException ex){ return error(ex); } @ExceptionHandler(Exception.class) public Result exceptionHadler(Exception ex){ return error(ex); } private Result error(Exception ex){ return Result.error(StringUtils.hasLength(ex.getMessage())?ex.getMessage():"操作失败"); } }

控制器类 package org.example.springboot3.bigevent.controller;

import jakarta.validation.constraints.Pattern; import org.example.springboot3.bigevent.entity.Result; import org.example.springboot3.bigevent.entity.User; import org.example.springboot3.bigevent.service.UserSerivce; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.validation.annotation.Validated; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController;

/**

Create by sean on 2024/6/14 */ @RequestMapping("/user/") @RestController @Validated public class UserController1 { @Autowired UserSerivce userSerivce; @RequestMapping("register") public Result register(@Pattern(regexp = "^\S{6,20} $",message = "用户名长度为6-20位") String username,@Pattern(regexp = "^\\S{8,20}$ ",message = "密码为8-20位") String password){ User user=userSerivce.findUserByName(username); if(user==null){//用户不存在,可以注册 int i=userSerivce.addUser(username,password); if(i!=1){ return Result.error("失败注册,请稍后重新注册!"); } }else{ return Result.error("该用户已存在,请重新注册!"); } return Result.success(); } }

响应 {"code":1,"message":"register.username: 用户名长度为6-20位, register.password: 密码为8-20位","data":null} 1 二、对象校验上面只有两个参数，我们可以直接校验，但是参数过多的时候我们都会直接使用对象校验。

1.实体类校验写在实体类对象对应属性上

package org.example.springboot3.bigevent.entity;

import com.baomidou.mybatisplus.annotation.IdType; import com.baomidou.mybatisplus.annotation.TableId; import jakarta.validation.constraints.Pattern; import lombok.Getter; import lombok.Setter; import lombok.ToString; import java.time.LocalDateTime;

@Getter @Setter @ToString public class User { @TableId(type=IdType.AUTO) private Integer id;//主键ID @Pattern(regexp = "^\S{6,20} $",message = "用户名长度为6-20位") private String username;//用户名 @Pattern(regexp = "^\\S{8,20}$ ",message = "密码为8-20位") private String password;//密码 private String nickname;//昵称 private String email;//邮箱 private String userPic;//用户头像地址 private LocalDateTime createTime;//创建时间 private LocalDateTime updateTime;//更新时间 }

2.控制器类 package org.example.springboot3.bigevent.controller;

import jakarta.validation.Valid; import jakarta.validation.constraints.Pattern; import org.example.springboot3.bigevent.entity.Result; import org.example.springboot3.bigevent.entity.User; import org.example.springboot3.bigevent.service.UserSerivce; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.validation.annotation.Validated; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController;

/**

Create by sean on 2024/6/14 */ @RequestMapping("/user/") @RestController @Validated public class UserController1 { @Autowired UserSerivce userSerivce; @RequestMapping("register1") public Result register1(@Valid User user){ if(userSerivce.findUserByName(user.getUsername())==null){//用户不存在,可以注册 int i=userSerivce.addUser(user.getUsername(),user.getPassword()); if(i!=1){ return Result.error("失败注册,请稍后重新注册!"); } }else{ return Result.error("该用户已存在,请重新注册!"); } return Result.success(); } }

全局异常处理对象数据校验信息太繁琐,我们简化到关键信息

package org.example.springboot3.config;

import jakarta.validation.ConstraintViolationException; import org.example.springboot3.bigevent.entity.Result; import org.springframework.util.StringUtils; import org.springframework.validation.BindingResult; import org.springframework.validation.FieldError; import org.springframework.web.bind.MethodArgumentNotValidException; import org.springframework.web.bind.annotation.ExceptionHandler; import org.springframework.web.bind.annotation.RestControllerAdvice; import java.util.stream.Collectors;

/**

Create by sean on 2024/6/14 */ @RestControllerAdvice public class GlobalExceptionHandler { @ExceptionHandler(MethodArgumentNotValidException.class) public Result exceptionHadler(MethodArgumentNotValidException ex){//对象数据校验信息太繁琐,我们简化到关键信息 BindingResult bindingResult = ex.getBindingResult(); if(bindingResult.hasFieldErrors()){ String message = bindingResult.getFieldErrors().stream().map(FieldError::getDefaultMessage).collect(Collectors.joining(";")); return error(message); } return error(ex); } @ExceptionHandler(Exception.class) public Result exceptionHadler(Exception ex){ return error(ex); } private Result error(String message){ return Result.error(message); } private Result error(Exception ex){ return Result.error(StringUtils.hasLength(ex.getMessage())?ex.getMessage():"操作失败"); } }

响应 {"code":1,"message":"用户名长度为6-20位;密码为8-20位","data":null}