Hibernate is an Object-Relational Mapping (ORM) framework that bridges the gap between object-oriented Java applications and relational databases. Let's explore its complete architecture:

1. Core Components of Hibernate Architecture

1.1. SessionFactory

• The central piece of Hibernate architecture as seen in your HibernateUtils class
• A thread-safe, immutable cache of compiled mappings for a single database
• Creates Session instances
• Holds second-level caches, connection pools, and dialect settings
• Usually created once at application startup and reused

1.2. Session

• A single-threaded, short-lived object representing a conversation between the application and the database
• Main runtime interface used by applications to perform CRUD operations
• Provides first-level cache (also called persistence context)
• Not thread-safe, should be used and then discarded
• In your application: Session session = getFactory().getCurrentSession();

1.3. Transaction

• Represents a unit of work with the database

• Abstracts the underlying transaction mechanism (JDBC, JTA)

• Used in your code as:

  Transaction tx = session.beginTransaction();
  try {
      // operations
      tx.commit();
  } catch (Exception e) {
      tx.rollback();
  }
  
  

1.4. Configuration