Where should I put the call to the Hibernate annotationConfiguration() to this be called only once?

I have in my web application some java beans (EJB 3.1) that make use of Hibernate SessionFactory and therefore I need to centralize the creation of this object since I just need one sessionFactory for the whole application. I mean, the following call:

SessionFactory sessionFactory = AnnotationConfiguration().configure().buidSessionFactory;开发者_如何学运维

I though to create a HibernateHelper class and put the method there, getting new sessions within the beans (because Hibernate sessions are lightweight objects) but then I don't know how to "force" such a class to be initialized together with the application (and only once).

Some insights?

Thanks a lot!

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This is very similar to another question: First Hibernate project where to place addAnnotatedClass() .

I would just add that if you are already using EJB 3.1, you are probably already using a Java EE Application Server (like JBoss AS). In this case, I would recommend not to use Hibernate directly, but use JPA. This way, the AS takes care of initializing the "entity manager" (like a Hibernate Session) for you once your application is deployed. You don't have to worry about this plumbing code.