SpringBoot3.4配置校验新特性的用法详解

package com.icoderoad.demo.config;


import jakarta.validation.Valid;
import jakarta.validation.constraints.*;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.validation.annotation.Validated;


import java.util.List;


@Validated
@ConfigurationProperties(prefix = "app.user")
public class UserProperties {


    @NotBlank(message = "用户名不能为空")
    private String username;


    @Email(message = "邮箱格式不正确")
    private String email;


    @Min(value = 18, message = "年龄不能小于18岁")
    private Integer age;


    @Valid
    private Address address;


    @Size(min = 1, message = "至少需要一个角色")
    private List<@NotBlank(message = "角色名称不能为空") String> roles;


    // Address是嵌套对象，需要加@Valid
    public static class Address {
        @NotBlank(message = "城市不能为空")
        private String city;


        @Pattern(regexp = "\d{6}", message = "邮编必须是6位数字")
        private String zipCode;


        // getter/setter
        public String getCity() {
            return city;
        }
        public void setCity(String city) {
            this.city = city;
        }
        public String getZipCode() {
            return zipCode;
        }
        public void setZipCode(String zipCode) {
            this.zipCode = zipCode;
        }
    }


    // getter/setter
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
    public Address getAddress() {
        return address;
    }
    public void setAddress(Address address) {
        this.address = address;
    }
    public List<String> getRoles() {
        return roles;
    }
    public void setRoles(List<String> roles) {
        this.roles = roles;
    }
}

app:
  user:
    username: "张三"
    email: "zhangsan@example.com"
    age: 25
    address:
      city: "上海"
      zipCode: "200000"
    roles:
      - "admin"
      - "user"

package com.icoderoad.demo.service;


import com.example.demo.config.UserProperties;
import org.springframework.stereotype.Service;


@Service
public class UserService {


    private final UserProperties userProperties;


    public UserService(UserProperties userProperties) {
        this.userProperties = userProperties;
    }


    public void printUserInfo() {
        System.out.println("用户名：" + userProperties.getUsername());
        System.out.println("邮箱：" + userProperties.getEmail());
    }
}

<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>

package com.icoderoad.demo.exception;


/**
 * 自定义配置校验异常
 */
public class ConfigValidationException extends RuntimeException {


    public ConfigValidationException(String message) {
        super(message);
    }
}

package com.icoderoad.demo.exception;


import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.boot.context.properties.bind.BindValidationException;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.validation.ObjectError;


import java.util.stream.Collectors;


@Configuration
public class ConfigValidationExceptionHandler {


    @Bean
    public static BeanFactoryPostProcessor configurationPropertiesValidator() {
        return beanFactory -> {
            try {
                // 手动触发bean初始化
            } catch (BeansException ex) {
                Throwable cause = ex.getCause();
                if (cause instanceof BindValidationException bindValidationException) {
                    String errorMessages = bindValidationException.getValidationErrors()
                            .getAllErrors()
                            .stream()
                            .map(ObjectError::getDefaultMessage)
                            .collect(Collectors.joining("; "));
                    throw new ConfigValidationException("配置属性校验失败：" + errorMessages);
                }
                throw ex;
            }
        };
    }
}

app:
  user:
    username: ""
    email: "wrong"
    age: 15
    address:
      city: ""
      zipCode: "12abc"
    roles:
      - ""