spring自定义校验注解（身份证，手机号）

实现自定义校验注解，ConstraintValidator接口

 

/**
 * Defines the logic to validate a given constraint {@code A}
 * for a given object type {@code T}.
 * <p>
 * Implementations must comply to the following restriction:
 * <ul>
 *     <li>{@code T} must resolve to a non parameterized type</li>
 *     <li>or generic parameters of {@code T} must be unbounded
 *     wildcard types</li>
 * </ul>
 * <p>
 * The annotation {@link SupportedValidationTarget} can be put on a
 * {@code ConstraintValidator} implementation to mark it as supporting
 * cross-parameter constraints. Check out {@link SupportedValidationTarget}
 * and {@link Constraint} for more information.
 *
 * @param <A> the annotation type handled by an implementation
 * @param <T> the target type supported by an implementation
 *
 * @author Emmanuel Bernard
 * @author Hardy Ferentschik
 */
public interface ConstraintValidator<A extends Annotation, T> {

	/**
	 * Initializes the validator in preparation for
	 * {@link #isValid(Object, ConstraintValidatorContext)} calls.
	 * The constraint annotation for a given constraint declaration
	 * is passed.
	 * <p>
	 * This method is guaranteed to be called before any use of this instance for
	 * validation.
	 * <p>
	 * The default implementation is a no-op.
	 *
	 * @param constraintAnnotation annotation instance for a given constraint declaration
	 */
	default void initialize(A constraintAnnotation) {
	}

	/**
	 * Implements the validation logic.
	 * The state of {@code value} must not be altered.
	 * <p>
	 * This method can be accessed concurrently, thread-safety must be ensured
	 * by the implementation.
	 *
	 * @param value object to validate
	 * @param context context in which the constraint is evaluated
	 *
	 * @return {@code false} if {@code value} does not pass the constraint
	 */
	boolean isValid(T value, ConstraintValidatorContext context);
}

　　

1.initialize方法

会在校验实例化后被调用，一般用于做些初始化工作。

 

2.isValid方法

实际执行验证的方法，第一个参数获取的是字段或对象实际对应的值，取决于类的枚举限定类型。第二个参数是ConstraintValidatorContext，上下文可以做些默认的设置。

本文使用自定义校验注解验证身份证是否符合要求。

 

 

@Constraint(validatedBy = IdCardValidator.class)
@Target({ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface IdCard {

    String message() default "身份证不合法";
    Class<?>[] groups() default {};
    Class<? extends Payload>[] payload() default {};
}

　

 

public class IdCardValidator implements ConstraintValidator<IdCard, String> {



    @Override
    public void initialize(IdCard constraintAnnotation) {
    

    }



    @Override
    public boolean isValid(String s, ConstraintValidatorContext constraintValidatorContext) {
        return IdCardUtils.checkIdCard(s);
    }
}

　　

    @IdCard
    private String idCard;