Spring Boot 3 is a powerful framework for building web applications in Java. It comes with a built-in embedded server, making it incredibly easy to run your applications locally. But have you ever wondered how to change the default port used by your Spring Boot application? This is where the localserverport property comes in handy.
What is localserverport?
The localserverport property is a powerful tool in Spring Boot 3 that lets you customize the port your application listens on during local development. By default, Spring Boot 3 runs on port 8080, but there might be times when you need to switch to a different port. Perhaps port 8080 is already in use by another application, or maybe you want to run multiple Spring Boot applications simultaneously on different ports. Whatever the reason, the localserverport property provides the flexibility to tailor your local development setup to your exact needs.
How to Use localserverport
You can set the localserverport property in a few different ways:
1. Application Properties File (application.properties)
The most common and straightforward method is to specify the localserverport in your application.properties file, which is located in the src/main/resources directory of your Spring Boot project. Simply add a line like this:
server.port=9090
Now, your application will run on port 9090 instead of the default 8080.
2. Application YAML File (application.yml)
You can also set the localserverport property in a application.yml file, which follows a YAML structure. The syntax is similar to the properties file:
server:
port: 9090
3. Environment Variables
If you prefer a more dynamic approach, you can set the localserverport via environment variables. In your terminal or command prompt, run the following command before launching your application:
export SERVER_PORT=9090
Then, your Spring Boot application will automatically pick up this environment variable and use port 9090.
4. Command Line Arguments
Finally, you can override the localserverport directly when you start your application from the command line:
java -jar your-application.jar --server.port=9090
localserverport in Action: A Real-World Example
Let's imagine you're building a Spring Boot application that serves as a backend for a web application. During development, you might need to run your Spring Boot application alongside other backend services, such as a database or a frontend server. If you're running all these services on the default port 8080, they will conflict with each other.
Using the localserverport property, you can easily resolve this conflict. Simply change the localserverport in your application.properties file (or use any of the other methods mentioned earlier) to a different port, like 9090. Now, your Spring Boot application will run smoothly on port 9090, coexisting harmoniously with other services on your development machine.
Troubleshooting
Sometimes, you might encounter situations where setting the localserverport doesn't work as expected. Here are some common reasons:
- Port Already in Use: If the port you've specified for localserverport is already being used by another application, your Spring Boot application won't be able to start. Check your running processes to see if anything is using the desired port.
- Incorrect Configuration: Ensure you've set the localserverport correctly in your
application.properties,application.yml, or environment variables. Double-check the syntax and spelling. - Application Restart: After changing the localserverport property, make sure to restart your Spring Boot application to ensure the change takes effect.
Conclusion
The localserverport property is a powerful tool that gives you complete control over the port used by your Spring Boot applications during development. By understanding how to use this property, you can avoid conflicts and ensure your applications run smoothly in your local environment. No matter your development workflow, localserverport provides the flexibility you need to tailor your Spring Boot experience to your exact needs.
