Hibernate session scope in Grails

Question

My question is about hibernate session scope in Grails :

1. Is session bound to a spring transaction?
2. A new session is created whenever a new request is created?
3. Or session is bound to a thread?

Can this be explained?

Thanks

Answer 1

Sessions are bound to transactions since the active PlatformTransactionManager is a HibernateTransactionManager . But be aware that controller requests do not run in transactions - only services are automatically transactional. You should refactor controllers that write to the database to use services to do that work so it's properly transactional.

A new session is created for each request and bound to the thread by the GrailsOpenSessionInViewInterceptor . This helps to avoid lazy loading exceptions and other issues. The session is flushed and closed at the end of the thread.

The ThreadLocal is in TransactionSynchronizationManager if you're curious; you can call TransactionSynchronizationManager.getResource(sessionFactory) (use def sessionFactory to get access to the SessionFactory ) to access the SessionHolder that holds the session.