Question

我的bean中有一个String列表。这些字符串是电子邮件，我想验证它们。

@Email
@ElementCollection(fetch = FetchType.LAZY)
@OrderColumn
private List<String> emails = new ArrayList<String>();

执行时，我收到了这个错误：

Caused by: javax.validation.UnexpectedTypeException: HV000030: No validator could be found for type: java.util.List<java.lang.String>.
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorManager.verifyResolveWasUnique(ConstraintValidatorManager.java:218)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorManager.findMatchingValidatorClass(ConstraintValidatorManager.java:193)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintValidatorManager.getInitializedValidator(ConstraintValidatorManager.java:97)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:125)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateComposingConstraints(ConstraintTree.java:233)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:102)
    at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:91)
    at org.hibernate.validator.internal.metadata.core.MetaConstraint.validateConstraint(MetaConstraint.java:83)
    at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraint(ValidatorImpl.java:547)
    ...

这样做的正确方法是什么？或者还有其他方法吗？

Answer 1

@Email仅适用于String而不是List，但您可以创建自己的验证码：

@Target({ ElementType.FIELD, ElementType.PARAMETER })
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = EmailCollectionValidator.class)
@Documented
public @interface EmailCollection {
    String message() default "Invalid Email";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};
}

验证

public class EmailCollectionValidator implements ConstraintValidator<EmailCollection, Collection<String>> {

    @Override
    public void initialize(EmailCollection constraintAnnotation) {

    }

    @Override
    public boolean isValid(Collection<String> value, ConstraintValidatorContext context) {
        if (value == null) {
            return false;
        }
        EmailValidator validator = new EmailValidator();
        for (String s : value) {            
            if (!validator.isValid(s, context)) {
                return false;
            }
        }
        return true;
    }
}

实现：

@EmailCollection
@ElementCollection(fetch = FetchType.LAZY)
@OrderColumn
private List<String> emails = new ArrayList<String>();

Answer 2

为@Email按照建议here验证集合实现额外的约束验证器是一种方法。请注意，如果遇到约束违规，您可能会遇到生成正确属性路径的问题。另请参阅HV-264。

如果您使用的是Java 8，则可以使用最新的Hibernate Validator版本（5.2.x），该版本支持Java 8类型级别注释。你可以写List<@Email String>之类的东西。但是，在这种情况下，您需要立即创建自己的@Email约束注释，并确保@Target包含ElementType.TYPE_USE。另见Hibernate Validator docs。

下一版本的Bean Validation（2.0）将与Java 8保持一致。所有提供的约束将具有ElementType.TYPE_USE，并且可以直接使用。另请参阅BVAL-202。

Answer 3

从 Hibernate Validator 6.0 及更高版本，您可以直接执行

Set<@Email String> emails

参考：
https://hibernate.atlassian.net/browse/HV-1094
https://github.com/hibernate/hibernate-validator/pull/512/commits/a24b47eb596737d2255bcd5a93298bd4f22097c3#diff-58473853b1e525d36641484e943b462d7b17cab5ca74357216f81f499400d7a6

JPA验证电子邮件字符串集合

3 个答案: