How port can close when Im close the program

Question

I dont want to change port number , but I receive an exception "Exception in thread "main" java.net.BindException: Address already in use: JVM_Bind"

ServerSocket server = new ServerSocket(1234, 180);

Answer 1

You have another process bound to the same port.

If you are using Windows then open CMD and run this command

netstat -aon | findstr 1234

you will get the process ID which you can find in task manager which is using that particular port. ie 1234 in your case