# 第一步：引入依赖

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-validation</artifactId><version>xxx</version>
</dependency>

# 第二步：实体类添加校验注解 

package com.holen;import jakarta.validation.constraints.Email;
import jakarta.validation.constraints.Min;
import jakarta.validation.constraints.NotBlank;
import jakarta.validation.constraints.Past;
import java.time.LocalDate;public class User  {@NotBlank(message = "姓名不能为空")private String name;@Min(value = 1, message = "年龄不能小于1")private int age;@Email(message = "邮箱格式错误")private String email;@Past(message = "生日必须为过去的时间")private LocalDate birthDay;
}

# 第三步：接口添加参数校验注解  

    @PostMapping("/update")private void updateUser(@RequestBody @Valid User user) {// 修改逻辑}