What does Java's Hibernate do and why do we need it?

We will discuss Hibernate in Java and its features in this article in an approachable way for newcomers. One of the most used Java frameworks is called Hibernate.



What Does Hibernate Mean in Java?


  • The implementations are internally managed by a Java framework called Hibernate, which also has an abstraction layer. The tasks involved in the implementations include, among other things, writing a query for CRUD activities or connecting to databases.


  • In essence, a framework is a piece of software that provides an abstraction over a variety of technologies, such as servlets, JDBC, and others.


  • The data is created, processed, and stored by Hibernate for eventual use through the application of persistence logic. Its features as an ORM tool, an open-source framework, and a lightweight framework give it an edge over others.

What does ORM mean?

The object-relational mapping (ORM) programming technique maps application domain model objects to relational database tables. The Java-based ORM tool known as Hibernate provides a framework for mapping application domain objects to relational database tables and vice versa.

What Functions Does an ORM Tool Have?

It entails mapping the object kept in the database. An ORM tool makes it simpler to create, change, and access data. It utilizes the Java API internally for database communication.


Classes For Generators In Hibernate

The "generator" class is a sub-element of id. It is used to generate a unique identification number for instances of persistent classes. There are numerous generator classes in the Hibernate Framework.

  • assigned
  • increment
  • sequence
  • Hilo
  • native
  • identity
  • seqhilo
  • uuid
  • guid
  • select
  • foreign
  • Sequence-identity

Hibernate Framework Is Necessary

      Hibernate gets rid of the disadvantages of other technologies like JDBC. Take a look at how it optimizes the jobs more successfully than JDBC.


  1. Hibernate fixes the problem with the JDBC's database dependence.
  2. Switching databases cost money when using JDBC; this problem is readily fixed by hibernating.
  3. Code portability is not a possibility while using JDBC, which hibernating can handle easily.
  4. Hibernate strengthens the connection between objects.
  5. It avoids the need for exception handling that comes with using JDBC.
  6. Hibernate defeats the object-level relationship.
  7. It shortens the code while enhancing readability by addressing the boilerplate issue.


Java Hibernate Overview

It is an open-source framework that is available to everyone at no cost. The source code for Hibernate, which permits modifications as well, is accessible online.


Having a substantially smaller installation package is a benefit of being a lightweight framework. When no execution container is employed, efficiency increases. Although Hibernate can work alongside several other technologies at once, it is also capable of working on its own.


Hibernate has a unique nature where it is not essential to implement hibernate API interfaces or extend from hibernate API classes due to the loose coupling of the classes used in hibernate application development.

Functionalities Supported by Hibernate:

Since Hibernate employs the Hibernate Query Language, it is database-independent.

  1. DDL procedures can be performed automatically.
  2. Hibernate supports Auto Primary Key Generation.
  3. There is support for the memory cache.
  4. Handling exceptions is not necessary while using Hibernate.
  5. Hibernated is the most important ORM tool, according to 

Databases Supported by Hibernate


The databases that Hibernate for Java supports are listed below.

  • Database Engine HSQL
  • MYSQL 
  • DB2/NT
  • FrontBase
  •  PostgreSQL
  •  DB2/NT
  • Informix Dynamic Server
  • Sybase SQL Server 
  • Database with Microsoft SQL Server


Hibernate is efficient and easy to use.

Technologies Supported by Hibernate

Hibernate supports a variety of technologies.

  • XDoclet Spring 
  • Maven
  • Plug-ins for Eclipse
  • J2EE
  • Let's look at a few benefits of using Java's hibernate.

Benefits Of Hibernate For Java:


  1. Open-source and lightweight - These features make it practical and efficient.
  2. Faster performance - Memory cache is useful for performance.
  3. Database Independence - Its database independence enables it to work with a variety of databases.
  4. We can avoid having to manually build tables by using automatic DDL processes.
  5. It handles mapping Java class databases using XML files without requiring any programming.
  6. We can quickly store and get data from the database using simple APIs.
  7. It has application server independence.
  8. Uses smart fetching strategies to minimize the amount of database access.
  9. It provides simple data querying.

Why is Hibernate preferable to JDBC?


  1. By removing much of the boilerplate code associated with the JDBC API, Hibernate improves the readability and aesthetics of the code.


  1. Hibernate supports inheritance, associations, and collections. These functionalities are not offered by the JDBC API.


  1. Hibernate implicitly provides transaction management; in fact, most queries cannot be executed outside of a transaction. We must write code for transaction management that makes use of the JDBC API's commit and rollback functions.


  1. We must write a lot of try-catch block code since the SQLException that the JDBC API throws is checked. Every time a JDBC call is made, it is typically repeated and used for transaction management. Because Hibernate covers JDBC exceptions and instead throws JDBCException or HibernateException unchecked exceptions, we don't need to write code to handle JDBC exceptions.


  1. The Java programming language is more so than the object-oriented Hibernate Query Language (HQL). Native SQL queries must be written for JDBC.


  1. JDBC queries are not cached, which results in poor performance. Caching is made possible by Hibernate, which improves efficiency.


  1. Hibernate gives an option through which we can also create database tables because JDBC tables must be present in the database.

Hibernate Caching

The two primary types of caching are:

  1. Cache from the First Level
  2. Cache at Second Level

First Level Cache: 

   The session object contains the first-level cache data. By default, it is turned on. The data in the first-level cache won't be accessible to the entire application. An application can make use of a variety of session objects.

Second-level cache:

    The Session Factory object houses the second-level cache data. The data stored in the second-level cache will be accessible to the entire application. But we have to explicitly activate it.