What is Hibernate and What are the feature of Hibernate?

What is Hibernate?

Hibernate is an open-source object-relational mapping (ORM) framework for Java applications. It provides a way to map Java objects to database tables and vice versa, making it easier to interact with relational databases.

What is top use cases of Hibernate?

Some of the top use cases of Hibernate include:

• Mapping Java classes to database tables and vice versa.
• Performing CRUD operations across all the major relational databases.
• Eliminating all the boiler-plate code that comes with JDBC and taking care of managing resources.
• Supporting transaction management to ensure there is no inconsistent data present in the system.
• Providing an abstraction layer between application and database.
• Mapping joins, collections, inheritance objects and visualizing how model classes represent database tables.

What are feature of Hibernate?

Features of Hibernate:

1. Hibernate Query Language (HQL): HQL is a query language provided by Hibernate that allows you to query your data using object-oriented syntax. This means that you can query your data using the same classes and properties that you used to define your domain model. HQL is more concise and easier to read than writing raw SQL queries, and it also helps to prevent SQL injection attacks.
2. Light-Weight: Hibernate is a lightweight framework that has a small footprint and does not require a lot of resources to run. This makes it a good choice for web applications and other resource-constrained environments.
3. Open-Source: Hibernate is an open-source framework, which means that it is free to use and modify. This makes it a good choice for projects that need to be flexible and customizable.
4. Scalability: Hibernate is a scalable framework that can be used to manage large and complex databases. This makes it a good choice for enterprise applications that need to handle a lot of data.
5. High Performance: Hibernate is a high-performance framework that can efficiently store and retrieve data. This makes it a good choice for applications that need to be fast and responsive.
6. Caching: Hibernate can cache frequently accessed data, which can improve the performance of your applications.
7. Database Independent: Hibernate is database independent, which means that it can be used with a variety of different databases. This makes it a good choice for projects that need to be portable.
8. ORM: Hibernate is an object-relational mapper (ORM) framework. This means that it can automatically map your Java classes to database tables and columns. This can save you a lot of time and effort, and it can also help to prevent errors.
9. Auto-Generation: Hibernate can automatically generate database tables and columns based on your Java classes. This can save you a lot of time and effort, and it can also help to ensure that your database schema is consistent with your domain model.
10. Easy to Learn: Hibernate is relatively easy to learn, even if you are not familiar with ORMs. There are many resources available to help you get started, including tutorials, documentation, and community forums.

What is the workflow of Hibernate?

Workflow of Hibernate:

• Domain Model Definition: Define Java classes representing your domain entities with annotations for mapping to database tables and columns.
• Configuration: Configure Hibernate with connection details, database schema, and mapping information.
• Session Management: Create sessions to interact with the database and perform CRUD operations on your domain objects.
• Persistence: Hibernate automatically translates object manipulations to SQL statements and interacts with the database.
• Closing: Close sessions and shut down Hibernate properly to release resources.

How Hibernate Works & Architecture?

The primary idea behind any ORM is to substitute writing database-specific SQL queries with object manipulation.

In simpler terms,

• You generate a POJO (Plain Old Java Object).
• Set values to its fields using setters.
• Instruct Hibernate to persist these objects.

Hibernate maps Java classes to corresponding database tables, including the mapping of Java data types to SQL data types.

Consequently, it eliminates the hassle of converting Java fields into SQL-supported data types, as Hibernate handles it automatically for you.

Additionally, it alleviates developers from the burden of result set handling.

Here’s an explanation of each of the topics in the image, which shows a block diagram of the architecture of a Java Persistence API (JPA) application using Hibernate:

Java Application: This represents the main application code written in Java, which uses Hibernate for data persistence.

Persistent Object: This refers to an object in the Java application that represents data stored in the database. Hibernate automatically maps this object to a database table and columns.

Session: This is a Hibernate object that represents a single unit of work with the database. It manages the persistence of objects and provides methods for CRUD (Create, Read, Update, Delete) operations.

Transaction: This is a unit of work within a session that ensures data consistency. All changes made within a transaction are either committed to the database or rolled back if there are errors.

JDBC: This stands for Java Database Connectivity, which is an API for connecting Java applications to relational databases. Hibernate uses JDBC under the hood to communicate with the database.

JNDI: This stands for Java Naming and Directory Interface, which is a service for looking up resources in a Java application. Hibernate can use JNDI to look up the DataSource object that provides connections to the database.

Connection Factory: This is an object that creates and manages database connections. Hibernate uses the Connection Factory to obtain connections to the database for each session.

Session Factory: This is a Hibernate object that creates and manages Hibernate sessions. It is responsible for configuring and initializing Hibernate for a specific database.

Transaction JTA: This refers to the Java Transaction API, which is a standard for managing transactions across multiple resources, such as databases and messaging systems. Hibernate can use JTA to manage transactions that span multiple databases.

Hibernate: This is the main component of the diagram, representing the open-source ORM framework that sits between the Java application and the database. It handles all the object-relational mapping and persistence logic.

Database: This represents the relational database where the persistent data is stored. Hibernate interacts with the database through the JDBC driver and the Connection Factory.