Servlet Filter that binds a Hibernate Session to the thread for the entire
processing of the request. Intended for the "Open Session in View" pattern,
i.e. to allow for lazy loading in web views despite the original transactions
already being completed.
This filter makes Hibernate Sessions available via the current thread, which
will be autodetected by transaction managers. It is suitable for service layer
transactions via HibernateTransactionManager
as well as for non-transactional execution (if configured appropriately).
NOTE: This filter will by default not flush the Hibernate Session,
with the flush mode set to FlushMode.NEVER. It assumes to be used
in combination with service layer transactions that care for the flushing: The
active transaction manager will temporarily change the flush mode to
FlushMode.AUTO during a read-write transaction, with the flush
mode reset to FlushMode.NEVER at the end of each transaction.
WARNING: Applying this filter to existing logic can cause issues that
have not appeared before, through the use of a single Hibernate Session for the
processing of an entire request. In particular, the reassociation of persistent
objects with a Hibernate Session has to occur at the very beginning of request
processing, to avoid clashes with already loaded instances of the same objects.
Looks up the SessionFactory in Spring's root web application context.
Supports a "sessionFactoryBeanName" filter init-param in web.xml;
the default bean name is "sessionFactory".