The Hibernate architecture includes many objects persistent object, session factory, transaction factory, connection factory, session, transaction etc.
There are 4 layers in hibernate architecture java application layer, hibernate framework layer, backhand api layer and database layer. Let's see the diagram of hibernate architecture:
Hibernate framework uses many objects session factory, session, transaction etc. along with existing Java API such as JDBC (Java Database Connectivity), JTA (Java Transaction API) and JNDI (Java Naming Directory Interface).
For creating the first hibernate application, we must know the elements of Hibernate architecture.
Session: The session object provides an interface between the application and data stored in the database.It is a short-lived object and wraps the JDBC connection. It is factory of Transaction, Query and Criteria. It holds a first-level cache (mandatory) of data. The org.hibernate.Session interface provides methods to insert update and delete the object. It also provides factory methods for Transaction, Query and Criteria.
The transaction object specifies the atomic unit of work. It is optional. The org.hibernate.Transaction interface provides methods for transaction management.
The SessionFactory is a factory of session and client of ConnectionProvider. It holds second level cache (optional) of data. The org.hibernate.SessionFactory interface provides factory method to get the object of Session.
It is a factory of JDBC connections. It abstracts the application from DriverManager or DataSource. It is optional.
It is a factory of Transaction. It is optional.