使用 Java EE 6 Bean 验证 [英] Using Java EE 6 Bean Validation

问题描述

我正在尝试使用此处指定的 Java EE 6 验证

I am trying to use Java EE 6 Validation as specified here

http://docs.oracle.com/javaee/6/教程/doc/gircz.html

我已经注释了一个简单的字段

I have annotated a simple field

@Max(11)
@Min(3)
private int numAllowed;

文档说对于内置约束，默认实现可用"但我如何指定它.我的约束检查没有开始.我希望它能够调用该字段的 setter 方法.我班上唯一的导入是

The docs says "For a built-in constraint, a default implementation is available" but how do I specify this. My constraints checks are not kicking in. I would expect it to work on calling of the setter method for the field. The only import in my class is

import javax.validation.constraints.Max;
import javax.validation.constraints.Min;

我如何/在哪里指定实现?我将约束放在一个简单的 POJO 中，而不是 @Entity 类中，这样可以吗?

How/where do I specify the implementation? I am putting the constraint on a filed in a simple POJO not an @Entity class, is this ok?

推荐答案

您对注释的使用很好.每个放心的人都有一个验证器实现.

Your use of the annotations is just fine. There's a validator implementation for each of those rest assured.

但是，在某些时候您需要触发此 POJO 的验证.如果它是一个 @Entity，它将是您的 JPA 提供程序触发验证，在您的情况下，您需要自己做.

However, at some point you need to trigger the validation of this POJO. If it were an @Entity it would be your JPA provider which triggers validation, in your case you need to do it yourself.

有一个 很好的 Hibernate Validator 文档，它是 JSR-303 的参考实现.

There's a nice documentation for Hibernate Validator which is the reference implementation for JSR-303.

示例

public class Car {
    @NotNull
    @Valid
    private List<Person> passengers = new ArrayList<Person>();
}

使用Car并验证:

Car car = new Car( null, true );

ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
Validator validator = factory.getValidator();
Set<ConstraintViolation<Car>> constraintViolations = validator.validate( car );

assertEquals( 1, constraintViolations.size() );
assertEquals( "may not be null", constraintViolations.iterator().next().getMessage() );

您可能还想阅读 bean 验证如何与其他框架集成(JPA、CDI 等).

You may also want to read how bean validation is integrated with other frameworks (JPA, CDI, etc.).

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