Spring Boot JpaRepository with Example

Last Updated : 29 Aug, 2025

JpaRepository is an interface in Spring Data JPA that makes working with databases much easier. It is built on top of the JPA (Java Persistence API) and provides all the basic methods you need for handling data.

With JpaRepository, you don’t need to write SQL queries for common operations like:

Saving data
Updating data
Deleting data
Fetching data

It also comes with built-in support for pagination (splitting data into pages) and sorting (arranging data in order).

Syntax:

public interface JpaRepository<T, ID>
extends PagingAndSortingRepository<T, ID>,
QueryByExampleExecutor<T>

Where:

T: The type of the entity (e.g., User, Product)
ID: The type of the primary key (e.g., Long, Integer)

Commonly Used JpaRepository Methods

Some of the most important methods that are available inside the JpaRepository are given below

1. saveAll(): Saves all given entities.

Syntax:

<S extends T> List<S> saveAll(Iterable<S> entities)

2. getById(): Returns a reference to the entity by its ID.

Syntax:

T getById(ID id)

3. flush(): Flushes all pending changes to the database.

Syntax:

void flush()

4. saveAndFlush(): Saves an entity and flushes changes instantly.

Syntax:

<S extends T> S saveAndFlush(S entity)

5. deleteAllInBatch(): Deletes multiple entities in a single batch query.

Syntax:

void deleteAllInBatch(Iterable<T> entities)

Step-by-Step Implementation Example

Step 1: Create a Spring Boot Project

Use IntelliJ IDEA or Spring Initializr. Add the following dependencies:

Spring Web
Spring Data JPA
H2 Database
Lombok

Here is the complete code for the pom.xml file.

Step 2: Project Structure

Create 4 packages as listed below and create some classes and interfaces inside these packages as seen in the below image

entity
repository
service
controller

👁 Packages

Step 3. Entity Class

Inside the entity package create a simple POJO class inside the Department.java file.

Step 4: Repository Interface

Inside the repository package create a simple interface and name the interface as DepartmentRepository. This interface is going to extend the JpaRepository as we have discussed above.

👁 Inside repository package

Example:

Step 5: Service Layer

Inside the service package create one interface named as DepartmentService and one class named as DepartmentServiceImpl.

Example A:

Example B:

Step 6: Controller Layer

Inside the controller package create one class named as DepartmentController.

Step 7: application.properties

Below is the code for the application.properties file

server.port=8082
# H2 Database
spring.h2.console.enabled=true
spring.datasource.url=jdbc:h2:mem:dcbapp
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect