我试图在我的Seam/Hibernate/JPA应用程序中利用EntityListener对象和回调方法。我在JBoss 5.1和后端的PostgreSQL 9.1上使用Seam 2.2管理的持久性上下文。我声明了以下实体:
@Entity(name = "TestEntity")
@EntityListeners(TestCallback.class)
@Table(name = "tbl_test")
public class TestEntity implements Serializable {
private static final long serialVersionUID = 2016897066783042092L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "xxx")
@SequenceGenerator(name = "xxx", sequenceName = "xxx")
@Index(name = "xxx")
@DocumentId
private Long id = null;
@Column
private String test = null;
...
}
以及以下EntityListener回调类:
public class TestCallback {
/**
* Logger for this class
*/
private Log logger = null;
public TestCallback() {
logger = Logging.getLog(TestCallback.class);
}
@PrePersist
public void prePersist(TestEntity e) {
logger.debug("prePersist(TestEntity) - start"); //$NON-NLS-1$
logger.debug("prePersist(TestEntity) - end"); //$NON-NLS-1$
}
@PostPersist
public void postPersist(TestEntity e) {
logger.debug("postPersist(TestEntity) - start"); //$NON-NLS-1$
logger.debug("postPersist(TestEntity) - end"); //$NON-NLS-1$
}
@PostLoad
public void postLoad(TestEntity e) {
logger.debug("postLoad(TestEntity) - start"); //$NON-NLS-1$
logger.debug("postLoad(TestEntity) - end"); //$NON-NLS-1$
}
@PreUpdate
public void preUpdate(TestEntity e) {
logger.debug("preUpdate(TestEntity) - start"); //$NON-NLS-1$
logger.debug("preUpdate(TestEntity) - end"); //$NON-NLS-1$
}
@PostUpdate
public void postUpdate(TestEntity e) {
logger.debug("postUpdate(TestEntity) - start"); //$NON-NLS-1$
logger.debug("postUpdate(TestEntity) - end"); //$NON-NLS-1$
}
@PreRemove
public void preRemove(TestEntity e) {
logger.debug("preRemove(TestEntity) - start"); //$NON-NLS-1$
logger.debug("preRemove(TestEntity) - end"); //$NON-NLS-1$
}
@PostRemove
public void postRemove(TestEntity e) {
logger.debug("postRemove(TestEntity) - start"); //$NON-NLS-1$
logger.debug("postRemove(TestEntity) - end"); //$NON-NLS-1$
}
}
但是，当我运行测试时，我没有看到我期望的所有回调方法都被调用。我已经对以下情况进行了测试:
但是，我看到的唯一回调是:
@PrePersist @PreRemove @PostLoad @PreUpdate 其余的回调未按预期执行。这是正常现象吗？我只是误会了吗？这与Seam管理交易的方式有关吗？还是我只是做错了什么？
我会很感激您能提供的任何帮助。
编辑:根据要求，这是我正在调用的确切代码以及收到的输出:
测试1:
public void runTest() {
logger.debug("runTest() - start"); //$NON-NLS-1$
TestEntity e = new TestEntity();
e.setTest("XXX");
this.entityManager.persist(e);
this.entityManager.flush();
this.entityManager.clear();
logger.debug("runTest() - end"); //$NON-NLS-1$
}
输出1:
12:27:56,307 INFO [STDOUT] 29735 DEBUG myapp.test.web.actions.test.TestAction - - runTest() - start
12:27:56,312 INFO [STDOUT] 29740 DEBUG myapp.test.entities.TestCallback - - prePersist(TestEntity) - start
12:27:56,312 INFO [STDOUT] 29740 DEBUG myapp.test.entities.TestCallback - - prePersist(TestEntity) - end
12:27:56,347 INFO [STDOUT] 29775 DEBUG myapp.test.web.actions.test.TestAction - - runTest() - end
测试2:
public void runTest2() {
logger.debug("runTest2() - start"); //$NON-NLS-1$
String sql = "SELECT DISTINCT t FROM TestEntity t";
Query q = this.entityManager.createQuery(sql);
List<TestEntity> l = q.getResultList();
for (int i = 0; i < l.size(); i++) {
String x = l.get(i).getTest();
logger.debug("runTest2() - String x=" + x); //$NON-NLS-1$
}
logger.debug("runTest2() - end"); //$NON-NLS-1$
}
输出2:
12:28:36,964 INFO [STDOUT] 70392 DEBUG myapp.test.web.actions.test.TestAction - - runTest2() - start
12:28:36,982 INFO [STDOUT] 70410 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - start
12:28:36,982 INFO [STDOUT] 70410 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - end
12:28:36,982 INFO [STDOUT] 70410 DEBUG myapp.test.web.actions.test.TestAction - - runTest2() - String x=XXX
12:28:36,983 INFO [STDOUT] 70411 DEBUG myapp.test.web.actions.test.TestAction - - runTest2() - end
测试3:
public void runTest3() {
logger.debug("runTest3() - start"); //$NON-NLS-1$
String sql = "SELECT DISTINCT t FROM TestEntity t";
Query q = this.entityManager.createQuery(sql);
List<TestEntity> l = q.getResultList();
for (int i = 0; i < l.size(); i++) {
l.get(i).setTest("YYY" + System.currentTimeMillis());
this.entityManager.persist(l.get(i));
}
this.entityManager.flush();
this.entityManager.clear();
Random rand = new SecureRandom();
q = this.entityManager.createQuery(sql);
l = q.getResultList();
for (int i = 0; i < l.size(); i++) {
this.entityManager.remove(l.get(i));
}
this.entityManager.flush();
this.entityManager.clear();
logger.debug("runTest3() - end"); //$NON-NLS-1$
}
输出3:
12:30:00,404 INFO [STDOUT] 153832 DEBUG myapp.test.web.actions.test.TestAction - - runTest3() - start
12:30:00,407 INFO [STDOUT] 153835 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - start
12:30:00,407 INFO [STDOUT] 153835 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - end
12:30:00,408 INFO [STDOUT] 153836 DEBUG myapp.test.entities.TestCallback - - preUpdate(TestEntity) - start
12:30:00,408 INFO [STDOUT] 153836 DEBUG myapp.test.entities.TestCallback - - preUpdate(TestEntity) - end
12:30:00,410 INFO [STDOUT] 153838 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - start
12:30:00,411 INFO [STDOUT] 153839 DEBUG myapp.test.entities.TestCallback - - postLoad(TestEntity) - end
12:30:00,414 INFO [STDOUT] 153842 DEBUG myapp.test.entities.TestCallback - - preRemove(TestEntity) - start
12:30:00,414 INFO [STDOUT] 153842 DEBUG myapp.test.entities.TestCallback - - preRemove(TestEntity) - end
12:30:00,453 INFO [STDOUT] 153881 DEBUG myapp.test.web.actions.test.TestAction - - runTest3() - end
最佳答案
抱歉，如果我给出错误的答案...我不知道Seam。
但是在您的主题中，您说的是“Hibernate/JPA”，目前尚不清楚。
您是使用SessionFactory的Session还是EntityManagerFactory的EntityManager来持久化实体？
有很大的不同，因为如果您将Seam与SessionFactory一起使用，则最大的不同是，默认情况下，JPA监听器(用于触发带注释的回调)未默认注册，而它们是与EntityManagerFactory一起注册的。
因此，可能您正在使用SessionFactory，而项目中配置了该 session 工厂的其他人仅注册了所有JPA回调监听器的子集。
看:
http://docs.jboss.org/hibernate/entitymanager/3.5/reference/en/html/configuration.html#d0e865
编辑:
好的，抱歉，您使用EntityManager ...
但是尝试将SessionFactory放在EntityManagerFactory后面，并查看注册了哪个事件监听器也许是个好主意。你一个人在那个应用上吗？如果有人尝试注册自定义/旧式事件监听器或其他内容，则他可能已覆盖了JPA事件监听器。
这可以通过以下方式实现:
EntityManager em = ...
Session session = (Session)em.getDelegage()
SessionFactoryImpl sessionFactoryImpl = (SessionFactoryImpl)session.getSessionFactory();
EventListeners el = sessionFactoryImpl.getEventListeners()
然后您可以查看其中的内容，例如，根据您的问题，您可以进行比较:
el.getPreLoadEventListeners()
el.getPreDeleteEventListeners()
并记住“默认行为”是:
http://docs.jboss.org/hibernate/stable/entitymanager/reference/en/html_single/#d0e865
似乎可以轻松地覆盖JPA默认监听器，请参见:
http://docs.jboss.org/hibernate/entitymanager/3.6/reference/en/html/listeners.html
如果您向我们展示您的persistence.xml，那就太好了
关于hibernate - Hibernate/JPA-实体监听器未正确调用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/8373024/