Spring Boot JPA

Why do we use JPA?

JPA is less labor-intensive than JDBC, SQL, and hand-written mapping because it is simpler, cleaner, and less time-consuming. JPA is appropriate for complex non-performance-oriented applications. JPA has the advantage over JDBC in that data is represented by objects and classes in JPA, whereas tables and records in JDBC represent data. It represents persistent data with POJO(Plain Old Java Object), which makes database programming easier.

Advantages of JPA 

The various benefits of JPA are as follows:

• JPA prevents DDL from being written in a database-specific dialect of SQL. Instead, it allows for XML mapping or the use of Java annotations.
• We can avoid writing DML in the database-specific dialect of SQL by using JPA.
• JPA will enable us to save and load Java objects and graphs without using any DML language.
• JPQL enables us to express queries in Java entities rather than SQL tables and columns when performing queries.

JPA Architecture

JPA is a database that allows us to store business objects as relational objects. It demonstrates how to define a POJO as an entity and how to manage relationships between entities.

The class-level architecture of JPA is depicted in the following diagram, which shows the core classes and interfaces defined in the javax persistence package. The following units make up the JPA architecture:

Features of JPA 

JPA have the following characteristics that are as follows:

• It's a flexible object-mapping abstraction and repository.
• It allows for persistence across multiple stores. 
• It generates queries dynamically based on the query method names.
• The domain base classes provide basic properties.
• It encourages open and transparent auditing.
• Custom repository code integration is possible.
• With the custom namespace, it's simple to integrate with Spring Framework.

What is Object-Relation Mapping?

Object-Relational Mapping (ORM) is the mapping of Java objects to database tables and vice versa. The ORM mapping serves as a connection between a relational database and a Java program.

The ORM layer is an adapter layer in the diagram above. It translates the language of object graphs into SQL and relational tables.

Between the application and the database is the ORM layer. It converts Java classes and objects into relational database objects that can be stored and managed. By default, the persist name is used as the table's name, and fields are used as columns. Each table row corresponds to an object once the application is set up.

Spring Boot JPA Starter Data

Spring Boot provides the spring-boot-starter-data-jpa starter dependency to connect Spring Boot applications efficiently to relational databases. The spring-boot-starter-data-jpa dependency is used internally by spring-boot-starter-data-jpa:

<dependency>    
<groupId>org.springframework.boot</groupId>    
<artifactId>spring-boot-starter-data-jpa</artifactId>    
<version>2.2.2.RELEASE</version>    
</dependency> 

Must Read Spring Tool Suite

FAQs

1. What is Spring Boot?
   Spring Boot is a Java-based open-source framework for developing microservices. Pivotal Team created it, and it is used to create stand-alone and production-ready spring applications.
    
2. What is JPA?
   Spring Boot JPA (Java Persistence API) is a Java standard for managing relational data in Java programs. It enables data to be accessed and stored between Java objects/classes and relational databases.
    
3. What are the features of Spring Boot JPA?
   The features of Spring Boot JPA are as follows:

• It's a flexible object-mapping abstraction and repository.
• It allows for persistence across multiple stores. 
• It generates queries dynamically based on the query method names.
• The domain base classes provide basic properties.
• It encourages open and transparent auditing.
• Custom repository code integration is possible.
• With the custom namespace, it's simple to integrate with Spring Framework.
   

Key Takeaways

We’ve learned about Spring Boot JPA features, architecture, and advantages in this article. 

You can also check our previous blogs on Introduction to Spring Boot, Spring Boot Auto-configuration, Spring Boot Annotations, and Spring Boot CLI. 

Explore more:

• STS Download
• spring mvc vs spring boot
• Has-A Relationship in Java

Thank you for reading!