Java参数校验详解之使用@Valid注解和自定义注解进行参数验证

<!--        validation组件依赖-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-validation</artifactId>
</dependency>

@PostMapping("/login")
public RespBean login(@Valid @RequestBody User user) {
    log.info("{}", user);
    return userService.login(user);
}

/**
 * @author Z
 * @date 2023/9/27 21:25
 */
@Data
public class User {
    @NotNull //账号非空
    //这个@Mobile是自定义判断注解，下面有对其的创建进行详细的讲解
    @Mobile(required = true) 
    private String mobile;
​
    @NotNull //密码非空
    @Length(min = 32)  //长度的限制
    private String password;
}

@Target({ElementType.METHOD, ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.CONSTRUCTOR, ElementType.PARAMETER, ElementType.TYPE_USE})
@Retention(RetentionPolicy.RUNTIME)
@Repeatable(NotNull.List.class)  //爆红了删除
@Documented
@Constraint(validatedBy = {}) //校验规则的定义
public @interface NotNull {
    String message() default "{javax.validation.constraints.NotNull.message}";
    //修改校验的消息
​
    Class<?>[] groups() default {};
​
    Class<? extends Payload>[] payload() default {};
​
}

 boolean required() default true;

/**
 * @author Z
 * @date 2023/9/28 8:53
 */
@Target({ElementType.METHOD, ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.CONSTRUCTOR, ElementType.PARAMETER, ElementType.TYPE_USE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
//自己定义校验规则的一个类：MobileValidator.class （手机号码校验规则类）
//将自定义规则类放进@Constraint(validatedBy={}) 中
@Constraint(validatedBy = {MobileValidator.class})
public @interface Mobile {
​
    boolean required() default true;
​
    //信息，抛出的是BindException，前端页面接收的话，我们要进行异常的捕获
    String message() default "手机号码格式错误";
​
    Class<?>[] groups() default {};
​
    Class<? extends Payload>[] payload() default {};
}

/**
 * 手机号码校验规则
 *
 * @author Z
 * @date 2023/9/28 8:56
 */
public class MobileValidator implements ConstraintValidator<Mobile, String> {
​
    private boolean required = false;
​
    //初始化：获取是否需要是必填的
    @Override
    public void initialize(Mobile constraintAnnotation) {
        //获取到填的值:true或者false
        required = constraintAnnotation.required();
    }
​
    @Override
    public boolean isValid(String value, ConstraintValidatorContext context) {
        //必填：则使用手机号码校验工具类去校验
        if (required){
            return ValidatorUtil.Mobile(value);
        //非必填：
        }else {
            if (StringUtils.isEmpty(value)){ //传的号码为空
                return true;
            }else {
                //传的号码非空，则使用手机号码校验工具类去校验
                return ValidatorUtil.isMobile(value);
            }
        }
    }
}

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
</dependency>

import org.apache.commons.lang3.StringUtils;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
​
/**
 * 手机号码校验类 (使用正则表达式)
 *
 * @author Z
 * @date 2023/9/27 21:45
 */
public class ValidatorUtil {
​
    private static final Pattern mobile_pattern = Pattern.compile("[1]([3-9])[0-9]{9}$");
​
    public static boolean Mobile(String mobile) {
        if (StringUtils.isEmpty(mobile)){
            return false;
        }
        Matcher matcher = mobile_pattern.matcher(mobile);
        return matcher.matches();
    }
}