How to change localhost port no in springboot?

To change the default port number of 8080 for a Spring Boot application, you can follow these steps:

1. Open the application.properties file located in the src/main/resources directory of your Spring Boot project.
2. Add the following line to the file: `server.port=port-number`, where "port-number" is the desired port number you want to use (e.g. 8081).
3. Save the file.

Now, when you run your Spring Boot application, it will use the new port number specified in the application.properties file instead of the default port 8080.

Alternatively, you can also specify the port number using a command-line argument when starting the application. For example, if you want to use port 8081, you can run the following command: `java -jar your-application.jar --server.port=8081` (replace "your-application.jar" with the name of your Spring Boot jar file). This will start the application on port 8081 instead of the default port.