详解SpringBoot中的参数校验(项目实战)

package com.yese.pojo;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.hibernate.validator.constraints.Length;

import javax.validation.constraints.*;

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class User {
 /**
 * 用户ID
 */
 @NotNull(message = "用户id不能为空")
 private Long userId;

 /**
 * 用户名
 */
 @NotBlank(message = "用户名不能为空")
 @Length(max = 20, message = "用户名不能超过10个字符")
 @Pattern(regexp = "^[\\u4E00-\\u9FA5A-Za-z0-9\\*]*$", message = "用户名限制：最多10字符，包含文字、字母和数字")
 private String username;

 /**
 * 密码
 */
 @NotBlank(message = "密码不能为空")
 private String password;

 /**
 * 手机号
 */
 @NotBlank(message = "手机号不能为空")
 @Pattern(regexp = "^[1][3,4,5,6,7,8,9][0-9]{9}$", message = "手机号格式有误")
 private String mobile;

 /**
 * 性别
 */
 @NotNull(message = "性别不能为空")
 private Integer sex;

 /**
 * 年龄
 */
 @NotNull(message = "年龄不能为空")
 @Min(value = 1, message = "年龄最小为1岁")
 @Max(value = 120, message = "年龄最大为120岁")
 private Integer age;

 /**
 * 邮箱
 */
 @NotBlank(message = "邮箱不能为空")
 @Email(message = "邮箱格式错误")
 private String email;

}

package com.yese.controller;

import com.yese.pojo.User;
import lombok.extern.slf4j.Slf4j;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
@Slf4j
public class UserController {

 /**
 * controller方法的入参里面在实体类前面加上@Validated
 */
 @PostMapping("/user")
 public void add(@RequestBody @Validated User user) {
 log.info("user====={}", user);
 }

}

package com.yese.config;


import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import javax.validation.ConstraintViolationException;
import java.util.HashMap;
import java.util.Map;
import java.util.StringJoiner;

/**
 * 全局异常处理器
 */
@RestControllerAdvice
public class GlobalExceptionHandler {
 /**
 * post方式提交json数据,参数校验失败后,会抛出一个MethodArgumentNotValidException
 */
 @ExceptionHandler(MethodArgumentNotValidException.class)
 public Map<String, Object> handleMethodArgumentNotValidException(MethodArgumentNotValidException e) {
 // 获取所有的错误
 // List<FieldError> fieldErrors = e.getBindingResult().getFieldErrors();
 // 获取错误提示
 // System.out.println(fieldErrors.get(0).getDefaultMessage());
 // 获取错误字段
 // System.out.println(fieldErrors.get(0).getField());

 // 将所有的错误提示使用";"拼接起来并返回
 StringJoiner sj = new StringJoiner(";");
 e.getBindingResult().getFieldErrors().forEach(x -> sj.add(x.getDefaultMessage()));

 // 此处通常定义一个全局相应对象返回
 Map<String, Object> map = new HashMap<>();
 // 此处状态码可以通过枚举或者常量定义
 map.put("code", 1001);
 map.put("msg", sj.toString());
 return map;
 }

 /**
 * get方式提交参数,参数校验失败后,会抛出一个ConstraintViolationException
 */
 @ExceptionHandler(ConstraintViolationException.class)
 public Map<String, Object> handleConstraintViolationException(ConstraintViolationException e) {
 StringJoiner sj = new StringJoiner(";");
 e.getConstraintViolations().forEach(x -> sj.add(x.getMessage()));

 Map<String, Object> map = new HashMap<>();
 map.put("code", 1001);
 map.put("msg", sj.toString());
 return map;
 }

}