JNDI-bound SessionFactory in Hibernate
A JNDI-bound Hibernate SessionFactory can simplify the lookup function of the factory and create new Sessions. This is not, however, related to a JNDI bound Datasource; both simply use the same registry.
If we need a SessionFactory bound to a JNDI namespace, specify a name (java:hibernate/SessionFactory) using the property hibernate.session_factory_name. If this property is omitted, the SessionFactory will not be bound to JNDI. This is especially useful in environments with a read-only JNDI default implementation (Its done in Tomcat, for example).
When binding the SessionFactory to JNDI, Hibernate will use the values of hibernate.jndi.url, hibernate.jndi.class to instantiate an initial context. If they are not specified, the default InitialContext will be used.
Hibernate will automatically place the SessionFactory in JNDI after when we call to cfg.buildSessionFactory(). This means you will have this call in some startup code, or utility class in your application, unless you use JMX deployment with the HibernateService (this is discussed later in greater detail).
If use a JNDI SessionFactory, an EJB or any other class, you can obtain the SessionFactory using a JNDI lookup.
It is recommended that you bind the SessionFactory to JNDI in a managed environment and use a static singleton otherwise. To shield your application code from these details, we also recommend to hide the actual lookup code for a SessionFactory in a helper class, such as HibernateUtil.getSessionFactory().