Hi,

We've implemented page hierarchies in Confluence using Parent/Child relationships. When a user tries to add a child on an existing hierarchy 3 levels deep, we get an assertion failure. This _only_ occurs under Jboss. It works fine on all other major app servers (resin, tomcat, orion)

Hibernate version: 2.1.6

Full stack trace of any exception that occurs:

09:55:55,968 ERROR [AssertionFailure] an assertion failure occured (this may indicate a bug in Hibernate, but is more likely
due to unsafe use of the session)
net.sf.hibernate.AssertionFailure: collection was not processed by flush()
at net.sf.hibernate.impl.SessionImpl$CollectionEntry.postFlush(SessionImpl.java:367)
at net.sf.hibernate.impl.SessionImpl.postFlush(SessionImpl.java:2834)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2241)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at org.springframework.orm.hibernate.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:463)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManag
er.java:373)
at com.atlassian.confluence.util.XWorkTransactionInterceptor.intercept(XWorkTransactionInterceptor.java:167)
at

Also,

java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextEntry(HashMap.java:782)
at java.util.HashMap$ValueIterator.next(HashMap.java:812)
at net.sf.hibernate.impl.Printer.toString(Printer.java:82)
at net.sf.hibernate.impl.SessionImpl.flushEverything(SessionImpl.java:2281)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2239)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at org.springframework.orm.hibernate.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:463)

Name and version of the database you are using:

HSQL db 1.7.1 (rrelevant as we can reproduce against all dbs)

Any hints on where to start investigating this would be appreciated.

Thanks,
Dave

Your Session handling is most likely broken.