What is Hibernate used for?

Hibernate is used for object-relational mapping (ORM) of data, allowing efficient interaction with databases using an object-oriented paradigm in Java. It abstracts low-level JDBC calls and SQL, providing a high-level API. Main goals:

• Reducing boilerplate code: Automates the conversion of Java objects to database records and vice versa.
• Database independence: With proper configuration, Hibernate can work with various DBMSs without changing application code.
• Transaction management: Provides a convenient mechanism for managing transactions.
• Cache management: Supports caching to improve performance.
• HQL (Hibernate Query Language): An object-oriented query language.

Example of simple entity mapping:

// Entity class corresponding to a database table
@Entity
@Table(name = "users")
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(name = "username")
    private String username;

    // Getters and setters
}