[Hibernate-issues] Hibernate Bug? [ConcurrentModificationException]

[William R. L. <wr...@ex...>]

Fellow Hibernaters,

I'm receiving an Exception in a Hibernate application I've built, and I'm
a bit confused as to why this might be happening.  The code at where the
Exception is thrown is quite simple, and I think this might be a bug in
Hibernate itself.  I've searched Google for this to no avail, and I'm
using the latest recommended Hibernate release as available on the site.

The exception I receive has a stacktrace as follows:

 java.util.ConcurrentModificationException
  at java.util.AbstractList$Itr.checkForComodification(Unknown Source)
  at java.util.AbstractList$Itr.remove(Unknown Source)
  at net.sf.hibernate.impl.SessionImpl.executeAll(SessionImpl.java:2101)
  at net.sf.hibernate.impl.SessionImpl.execute(SessionImpl.java:2061)
  at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2005)
  at net.sf.hibernate.transaction.JDBCTransaction.commit(
       JDBCTransaction.java:57
     )
  at org.express.ftpsrv.ConnectionHandler.<init>(ConnectionHandler.java:72)
  at org.express.ftpsrv.ConnectionListener.accept(ConnectionListener.java:56)
  at org.express.ftpsrv.ConnectionListener.main(ConnectionListener.java:19)

And the code at ConnectionHandler.java:72 that causes this looks like:

  52:this.ftpSession = new FtpSession();
  53:
  54:/* ftpSession.setSessionId() does not operate on the unique
  55: * 'id' field that is also part of the ftpSession object.
  56: */
  57:ftpSession.setSessionId(UniqueGenerator.makeUniqueNumber());
  58:
  59:Date currentDate = new Date();
  60:currentDate.setTime(System.currentTimeMillis());
  61:this.ftpSession.setBegTime(currentDate);
  62:
  63:net.sf.hibernate.Session hSession = null;
  64:Transaction transaction = null;
  65:
  66:try
  67:{
  68:  hSession = SessionHolder.getSession();
  69:
  70:  transaction = hSession.beginTransaction();
  71:  hSession.save(this.session);
  72:  transaction.commit();
  73:} catch (HibernateException e)
  74:{
  75:  transaction.rollback();
  76:}

I'd like to point out that this seems to be an intermittent thing,
occurring more often when I instantiate many objects quickly (the quoted
lines 52-72, above, are within a cronstructor in the Object).

Does anyone have any ideas as to what might be happening or where I might
look for additional information in order to track down this bug?

Thanks, in advance, for any response on this.

--          _ 
__ __ ___ _| | William R. Lorenz <wr...@ex...> 
\ V  V / '_| | http://www.clevelandlug.net/ ; "Every revolution was 
 \./\./|_| |_| first a thought in one man's mind." - Ralph Waldo Emerson