JPA ConstraintViolation vs Rollback

Question

我想我刚刚发现两个不同的JPA实现在约束违规和回滚方面的工作方式不同.

@Test(expectedExceptions = @@.class) // CVE or RB?
public void testXXX() {
    final EntityManager manager = LocalPU.createEntityManager();
    try {
        final EntityTransaction transaction = manager.getTransaction();
        transaction.begin();
        try {
            manager.persist(<wrong>); // this is where CVE coming from
            transaction.commit();     // this is where RB coming from
        } catch (RollbackException re) {
            // <---------------------------------------- hibernate here
            throw re;
        } catch (ConstraintViolationException cve) {
            // <---------------------------------------- eclipselink here
            transaction.rollback();
            throw cve;
        } catch (Exception e) {
            transaction.rollback();
            e.printStackTrace(System.err);
            Assert.fail(e.getMessage());
        }
    } finally {
        manager.close();
    }
}

哪个实施工作正常？

UPDATE

NameMustNotBeNull.java

@Entity
@Table(name = "NAME_MUST_NOT_BE_NULL")
public class NameMustNotBeNull {

    protected NameMustNotBeNull() {
        this(null);
    }

    public NameMustNotBeNull(final String name) {
        super();

        this.name = name;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.TABLE,
                    generator = "NAME_MUST_NOT_BE_NULL_ID_GENERATOR")
    @TableGenerator(name = "NAME_MUST_NOT_BE_NULL_ID_GENERATOR",
                    table = PrimaryKeyValue.TABLE,
                    pkColumnName = PrimaryKeyValue.PK_COLUMN_NAME,
                    valueColumnName = PrimaryKeyValue.VALUE_COLUMN_NAME,
                    pkColumnValue = "NAME_MUST_NOT_BE_NULL_ID")
    @NotNull
    @XmlTransient
    private Long id;

    @Basic(optional = false)
    @Column(name = "NAME", nullable = false)
    @NotNull
    private String name;
}

NameMustNotBeNullTest.java

public class NameMustNotBeNullTest {

    @Test(expectedExceptions = RollbackException.class)
    public void testNullName() {

        final EntityManager manager = LocalPU.createEntityManager();
        try {
            final EntityTransaction transaction = manager.getTransaction();
            transaction.begin();
            try {
                final NameMustNotBeNull entity = new NameMustNotBeNull(null);
                try {
                    manager.persist(entity);
                } catch (ConstraintViolationException cve) {
                    System.out.println(cve.toString());
                }
                transaction.commit();
                Assert.fail("persisted with null name");
            } catch (RollbackException re) {
                System.out.println(re.toString());
                throw re;
            } catch (Exception e) {
                transaction.rollback();
                e.printStackTrace(System.err);
                Assert.fail(e.getMessage());
            }
        } finally {
            manager.close();
        }
    }
}

persistence.xml中

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">

  <persistence-unit name="localPU" transaction-type="RESOURCE_LOCAL">

    <!-- I'm testing with one of following providers uncommented -->
    <!--<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>-->
    <provider>org.hibernate.ejb.HibernatePersistence</provider>

    <class>....persistence.NameMustNotBeNull</class>

    <properties>

      <property name="javax.persistence.jdbc.driver"
                value="org.apache.derby.jdbc.EmbeddedDriver"/>
      <property name="javax.persistence.jdbc.url"
                value="jdbc:derby:memory:corrsDB;create=true"/>
      <!--<property name="javax.persistence.jdbc.user" value=""/>-->
      <!--<property name="javax.persistence.jdbc.password" value=""/>-->

      <!-- eclipselink -->
      <property name="eclipselink.create-ddl-jdbc-file-name" value="target/createDDL.jdbc"/>
      <property name="eclipselink.ddl-generation" value="create-tables"/>
      <property name="eclipselink.ddl-generation.output-mode" value="both"/>
      <property name="eclipselink.drop-ddl-jdbc-file-name" value="target/dropDDL.jdbc"/>
      <property name="eclipselink.logging.level.sql" value="INFO"/>
      <property name="eclipselink.logging.parameters" value="false"/>
      <property name="eclipselink.target-database" value="Derby"/>

      <!-- hibernate -->
      <property name="hibernate.archive.autodetection" value="class" />
      <property name="hibernate.format_sql" value="true" />
      <property name="hibernate.hbm2ddl.auto" value="create-drop"/>
      <property name="hibernate.show_sql" value="false" />
      <property name="hibernate.dialect" value="org.hibernate.dialect.DerbyDialect"/>

    </properties>
  </persistence-unit>
</persistence>

org.eclipse.persistence.jpa.PersistenceProvider

Running ...NameMustNotBeNullTest
1? 17, 2013 11:45:14 ?? org.hibernate.validator.internal.util.Version <clinit>
INFO: HV000001: Hibernate Validator 4.3.0.Final
javax.validation.ConstraintViolationException: Bean Validation constraint(s) violated while executing Automatic Bean Validation on callback event:'prePersist'. Please refer to embedded ConstraintViolations for details.
javax.persistence.RollbackException: Transaction rolled back because transaction was set to RollbackOnly.

org.hibernate.ejb.HibernatePersistence

Running ...NameMustNotBeNullTest
1? 17, 2013 11:50:14 ?? org.hibernate.validator.internal.util.Version <clinit>
INFO: HV000001: Hibernate Validator 4.3.0.Final
javax.persistence.RollbackException: Error while committing the transaction

如您所见,两个提供程序似乎都启用了Bean Validation.

EclipseLink会在EntityManager#persist()标记为回滚的情况下抛出CVE .
并且Hibernate抛出RB EntityTransaction#commit().

Answer 1

以下是有关您所拥有行为的更详细信息来源.

根据JPA 2规范(第102页)

如果validate方法返回的ConstraintViolation对象集不为空,则持久性提供程序必须抛出包含对返回的ConstraintViolation对象集的引用的javax.validation.ConstraintViolationException,并且必须将事务标记为回滚.

而且来自hibernate doc

如果发现实体无效,则ConstraintViolationException会传播约束违规列表,这会暴露一组ConstraintViolations.

在提交时发生违规时,此异常将包装在RollbackException中.否则,[Hibernate Validator]返回ConstraintViolationException(例如,在调用flush()时).)

此外,来自jpa 2规格(第101页)

默认情况下,默认Bean验证组(组默认值)将根据预先持久化和更新前的生命周期验证事件进行验证

将所有这些放在一起,我有点困惑,因为在我看来,HibernatePersistenceProvider的行为不遵循JPA 2规范,因为:

• 验证必须在"pre-presist"上进行
• 持久性提供程序必须抛出 ConstraintViolationException

显然,在你的情况下,调用时(以及使用HibernatePersistenceProvider时)ConstraintViolationException不会抛出persist.

所以根据我的理解并回答你的问题:

• eclipselink是对的
• 休眠是错误的

(注意:我希望其他人可以确认或不同意我的分析)

重要编辑

我对自己的结论感到困惑.所以我试图重现OP所描述的行为,我无法立即重现这种行为.

我所做的与OP描述的非常相似:

• 设置一个小项目,一个实体与一个@NotNull字段.
• 尝试@NotNull在简单测试中持久化()一个带null的实例.
• 断言persist()操作抛出一个javax.validation.ConstraintViolationException+标记事务为rollback only
• 使用eclipselink作为持久性提供程序时执行此操作 - >成功
• 使用hibernate作为持久性提供程序时执行此操作 - >成功

我的测试和测试之间的主要区别是描述OP是id生成.在我成功的测试中,我使用的很简单@GeneratedValue.

将id生成策略更改为:

@GeneratedValue(strategy = GenerationType.TABLE,
        generator = "NAME_MUST_NOT_BE_NULL_ID_GENERATOR")
@TableGenerator(name = "NAME_MUST_NOT_BE_NULL_ID_GENERATOR",
        pkColumnValue = "NAME_MUST_NOT_BE_NULL_ID")

我找到了OP描述的确切行为:

• 一个javax.validation.ConstraintViolationException被抛出persist()使用的EclipseLink时.
• persist()使用hibernate时完全没有异常.

因此,在使用Hibernate +时 strategy = GenerationType.TABLE:行为是不同的.我很确定它不符合JPA2规范.