Spring Boot CRUD Example with H2 Database: Step-by-Step Guide

In this tutorial, you’ll learn how to build a Spring Boot CRUD (Create, Read, Update, Delete) application using the H2 in-memory database. We will use Java record for the DTO (Data Transfer Object) and follow best practices by keeping the conversion logic in the service layer.

What You’ll Learn:

• Setting up a Spring Boot project with H2.
• Configuring Spring Boot to use H2 as an in-memory database.
• Implementing CRUD operations with Spring Data JPA.
• Using Java record as DTOs for transferring data.
• Testing RESTful APIs using Postman.

Prerequisites

Before starting, ensure you have:

• Java Development Kit (JDK) 17 or later
• Apache Maven (for project management)
• IDE (e.g., IntelliJ IDEA, Eclipse, or VS Code)
• Postman (to test the APIs)

Step 1: Setting Up the Project

1.1 Create a Spring Boot Project

Open Spring Initializr.

Configure the project metadata:

• Project: Maven