Commit fails when an explicit flush called before ------------------------------------------------- Key: HHH-6810 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-6810 Project: Hibernate Core Issue Type: Bug Components: entity-manager Affects Versions: 3.6.5 Environment: Hibernate 3.6.5 / HSQLDB 1.8.0.10 Reporter: Marek Matczak Attachments: hibernate.properties, SomeItem.java, SomeOtherThing.java, SomeUser.java, test-case.zip We have a simple model: SomeUser may have SomeItems (one-to-many relationship); SomeOtherThing is related neither to SomeUser nor to SomeItem (see the attached files for details). We register a pre insert event listener in which SomeOtherThings are queried when a new SomeUser is inserted: {code:title=SomeUserPreInsertEventListenerQueryingSomeOtherThings.java|borderStyle=solid} public class SomeUserPreInsertEventListenerQueryingSomeOtherThings implements PreInsertEventListener { private static final long serialVersionUID = 7457725085286340589L; public boolean onPreInsert(PreInsertEvent event) { Class<? extends Object> currentClass = event.getEntity().getClass(); if (SomeUser.class.equals(currentClass)) { event.getSession().createCriteria(SomeOtherThing.class).list(); } return false; } } {code} When we try to insert some data, the following code fails: {code:title=Test.java|borderStyle=solid} Configuration cfg = new Configuration() // hibernate.properties is loaded here .addAnnotatedClass(SomeUser.class) // .addAnnotatedClass(SomeItem.class) // .addAnnotatedClass(SomeOtherThing.class);// cfg.getEventListeners().setPreInsertEventListeners( new PreInsertEventListener[] { new SomeUserPreInsertEventListenerQueryingSomeOtherThings() }); SessionFactory sessionFactory = cfg.buildSessionFactory(); Session session = sessionFactory.openSession(); session.beginTransaction(); SomeUser user = new SomeUser(); user.setName("Some name"); session.save(user); SomeItem item = new SomeItem(); item.setDescription("Some description"); user.addItem(item); session.save(item); // for some reason we want to call a flush here session.flush(); // 1st flush session.getTransaction().commit(); // 2nd flush {code} Our analysis shown that the 1st flush (which triggers the SomeUserPreInsertEventListenerQueryingSomeOtherThings) left the persistence context in some illegal state so that the commit (which issues another flush) fails: org.hibernate.HibernateException: Found two representations of same collection: bug.report.model.SomeUser.items at org.hibernate.engine.Collections.processReachableCollection(Collections.java:175) at org.hibernate.event.def.FlushVisitor.processCollection(FlushVisitor.java:60) at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:122) at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:83) at org.hibernate.event.def.AbstractVisitor.processEntityPropertyValues(AbstractVisitor.java:77) at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:165) at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:219) at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:99) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1216) at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:383) at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:133) If we either didn't call the 1st flush or didn't register the event listener at all, the code would succeed. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira