application properties配置8083端口后仍提示8080占用的解决方法

Hey there, let's troubleshoot why your application is still clinging to port 8080 even though you've set server.port=8083 in your config file. Here are the most common fixes to get it up and running on your desired port:

• Double-check your configuration file details
  First, make sure you're working with the right file and location:

  • Confirm the filename is application.properties (note the dot, not a space—typos here are way too common!).
  • Verify it’s placed directly in the src/main/resources directory (not nested in a subfolder, which would stop Spring from picking it up by default).
  • If you’re using Spring profiles (like dev/prod), check if an environment-specific config file (e.g., application-dev.properties) is overriding the main one—you’ll need to set server.port=8083 in the active profile’s file too.

• Check for overriding startup parameters
  Command-line or IDE launch settings can easily override your config file:

  • If you’re starting the app via a JAR command, look for something like --server.port=8080 in the arguments. Remove that or swap it to --server.port=8083.
  • In your IDE (IntelliJ, Eclipse, etc.), open your Run/Debug configuration. Check the Program arguments or VM options sections for -Dserver.port=8080—update this to 8083 if it’s present.

• Clean and rebuild your project
  Stale build artifacts or IDE caches can prevent config changes from taking effect:

  • For Maven projects, run mvn clean install in your terminal to wipe old builds and generate fresh ones.
  • For Gradle projects, use ./gradlew clean build.
  • Restart your IDE and clear its cache (e.g., in IntelliJ: File > Invalidate Caches... > Invalidate and Restart).

• Ensure port 8083 isn’t occupied
  Even though the error mentions 8080, it’s worth confirming your target port is free:

  • Windows: Run netstat -ano | findstr :8083 to find the PID of the process using the port, then kill it with taskkill /F /PID <your-pid>.
  • Linux/Mac: Use lsof -i :8083 or netstat -tulpn | grep :8083 to locate the process, then terminate it with kill -9 <your-pid>.

• Check for hardcoded ports in your code
  Sometimes developers hardcode ports in configuration classes or the main application file:

  • Search your codebase for instances of server.port or direct port assignments (e.g., in a @Configuration class). Make sure these are either removed or set to read from your application.properties file.

内容的提问来源于stack exchange，提问作者Trts