JMX MBean for Hibernate Statistics and Seam

[asookazian]

I am following the instructions in this wiki:  My Link

And have successfully installed the MBean for Hibernate Statistics (cool!) as per Publish a per session factory JMX MBean

Now I need to complete the implementation for the 2nd part (When the SessionFactory is closed, we need to unregister the MBean)

So that means I need to know when/how and which class/method actually calls entityManagerFactory.close();

I didn't find this in the Seam core code for 2.0.2-FP except in org.jboss.seam.persistence.EntityManagerFactory but there's a comment there which states:

A Seam component that bootstraps an EntityManagerFactory,
for use of JPA outside of Java EE 5 / Embedded JBoss.

I am running my app in JBoss 4.2.x.  So what is the best approach for solving this problem so that I can successfully unregister the MBean when the SessionFactory is closed?

I'm hoping to @Observe a raised event if possible or something similarly easy.

I am hoping to eventually integrate this solution into my HibernateUtil class.

[asookazian]

I shut down JBoss and seeing the following in console:

09:48:18,743 INFO  [SessionFactoryImpl] closing

So apparently the implementation of EntityManagerFactory interface is SessionFactoryImpl class when the persistence provider is Hibernate?

Anyways, so must I use a Hibernate interceptor to solve this now?  How can I capture this event and continue my processing to unregister the MBean?

[asookazian]

Here is the code in org.hibernate.impl.SessionFactoryImpl class.  Note the last lines:

observer.sessionFactoryClosed( this );
eventListeners.destroyListeners();

Has anyone actually used this part of the Hibernate Core API for event tracking purposes?  thx.

/**
      * Closes the session factory, releasing all held resources.
      *
      * <ol>
      * <li>cleans up used cache regions and "stops" the cache provider.
      * <li>close the JDBC connection
      * <li>remove the JNDI binding
      * </ol>
      *
      * Note: Be aware that the sessionfactory instance still can
      * be a "heavy" object memory wise after close() has been called.  Thus
      * it is important to not keep referencing the instance to let the garbage
      * collector release the memory.
      */
     public void close() throws HibernateException {

          if ( isClosed ) {
               log.trace( "already closed" );
               return;
          }

          log.info("closing");

          isClosed = true;

          Iterator iter = entityPersisters.values().iterator();
          while ( iter.hasNext() ) {
               EntityPersister p = (EntityPersister) iter.next();
               if ( p.hasCache() ) {
                    p.getCacheAccessStrategy().getRegion().destroy();
               }
          }

          iter = collectionPersisters.values().iterator();
          while ( iter.hasNext() ) {
               CollectionPersister p = (CollectionPersister) iter.next();
               if ( p.hasCache() ) {
                    p.getCacheAccessStrategy().getRegion().destroy();
               }
          }

          if ( settings.isQueryCacheEnabled() )  {
               queryCache.destroy();

               iter = queryCaches.values().iterator();
               while ( iter.hasNext() ) {
                    QueryCache cache = (QueryCache) iter.next();
                    cache.destroy();
               }
               updateTimestampsCache.destroy();
          }

          settings.getRegionFactory().stop();

          if ( settings.isAutoDropSchema() ) {
               schemaExport.drop( false, true );
          }

          try {
               settings.getConnectionProvider().close();
          }
          finally {
               SessionFactoryObjectFactory.removeInstance(uuid, name, properties);
          }

          observer.sessionFactoryClosed( this );
          eventListeners.destroyListeners();
     }

[asookazian]

Seam in Action does not list any Hibernate events as built-in raised events:

Here’s a list of some of the events that
Seam raises:
■ Seam container initialized
■ Context variable assignment (added, removed)
■ Component life-cycle events (created, destroyed)
■ Scope events (created, destroyed)
■ Authentication events
■ Transaction events (before complete, commit, rollback)
■ Exception events (handled, not handled)
■ Conversation, page flow, business process, and task boundaries
■ JSF phase transitions (before, after)
■ JSF validation failed
■ User preference change (theme, time zone, locale)

Unless possibly component life-cycle event for this?  Not sure which component is involved here...