Message Title

I think adding an initial isClosed() check to getTransaction(), at the beginning would help, something like:

   public Transaction getTransaction() throws HibernateException {
	if (isClosed() ) {
                return null
        }
	if ( getFactory().getSessionFactoryOptions().getJpaCompliance().isJpaTransactionComplianceEnabled() ) {
		// JPA requires that we throw IllegalStateException if this is called
		// on a JTA EntityManager
		if ( getTransactionCoordinator().getTransactionCoordinatorBuilder().isJta() ) {
			if ( !getFactory().getSessionFactoryOptions().isJtaTransactionAccessEnabled() ) {
			    throw new IllegalStateException( "A JTA EntityManager cannot use getTransaction()" );
			}
		}
	}
	return accessTransaction();
   }