Spring Boot SQLite Example

A simple Spring Boot project that demonstrates how to connect to a SQLite database and display data on a web page. Intended as a beginner tutorial for students learning web development.

Prerequisites

• Java 17 or later — Download JDK
• Git — to clone the repository

No need to install Gradle separately. The project includes the Gradle wrapper (gradlew).

How to run

1. Clone the repository and navigate into the project folder:

   git clone <repository-url>
   cd spring-boot-project

2. Build the project:

   ./gradlew build -x test

3. Run the application:

   ./gradlew bootRun

4. Open your browser and go to http://localhost:8080

Troubleshooting

Port 8080 is already in use

If you see this error when running ./gradlew bootRun:

Web server failed to start. Port 8080 was already in use.

It means a previous instance of the application is still running. To fix it, find and stop that process:

On macOS / Linux:

fuser -k 8080/tcp

On Windows:

netstat -ano | findstr :8080
taskkill /PID <PID> /F

Replace <PID> with the number from the first column. Then run ./gradlew bootRun again.

Project structure

src/
├── main/
│   ├── java/com/example/demo/
│   │   ├── DemoApplication.java      # Entry point
│   │   ├── Student.java              # JPA entity
│   │   ├── StudentRepository.java    # Spring Data repository
│   │   └── StudentController.java    # Web controller
│   └── resources/
│       ├── application.properties    # Database configuration
│       └── templates/index.html      # Thymeleaf web page

Technologies used

• Spring Boot 3.4.3 — application framework
• Spring Data JPA — database access
• SQLite — lightweight file-based database
• Thymeleaf — server-side HTML templating

How SQLite is integrated with Spring Boot

Spring Boot normally expects databases like MySQL or PostgreSQL. Connecting to SQLite requires three small additions:

1. Dependencies (build.gradle)

implementation 'org.hibernate.orm:hibernate-community-dialects' // SQLite dialect for Hibernate
runtimeOnly 'org.xerial:sqlite-jdbc:3.45.1.0'                  // JDBC driver for SQLite

2. Configuration (application.properties)

spring.datasource.url=jdbc:sqlite:test.db               # path to the SQLite file
spring.datasource.driver-class-name=org.sqlite.JDBC
spring.jpa.database-platform=org.hibernate.community.dialect.SQLiteDialect
spring.jpa.hibernate.ddl-auto=update                    # auto-creates tables on startup

3. Entity class (Student.java)

A plain Java class annotated with @Entity is all that is needed. Spring Data JPA maps it to a table in the SQLite file automatically.

@Entity
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String name;
}

When the app starts, Hibernate reads the dialect, connects to test.db (creating the file if it does not exist), and creates the student table based on the entity.