Java Socket.bind(null);

According to the documentation passing null to the Socket.bind() method will cause system to automatically assign an ephemeral port number to the socket.

Whenever I try to do it, I am getting "SocketException: Already Bound".

I tried reading into documentation, but being new to programming I don't fully understand everything that's there yet. Isn't Socket.bind(null) supposed to find an available port?

Also if I am being daft and following bad practices anywhere else in the code you are welcome to scorn me.

Below is the fragment of the code:

public static void main(String[] args) {        ServerSocket ss = null;        try {            ss = new ServerSocket(8080);        } catch (IOException e) {            e.printStackTrace();      }        System.out.println("Listening on port " + ss.getLocalPort());        Socket socket = null;        try {            socket = ss.accept();          socket.bind(null);      //crashes here            Thread connection = new Thread(new Echo(socket));          connection.run();        } catch (IOException e) {          // TODO Auto-generated catch block          e.printStackTrace();        }    }  

https://stackoverflow.com/questions/66792044/java-socket-bindnull March 25, 2021 at 10:04AM