Custom XML message socket listener

[Carl Bradbury]

I'm trying to figure out the most elegant way to write a listener thread that constantly listens on a given Socket for incoming TCP/IP messages.

Each individual TCP/IP message is composed of 4 bytes followed an XML document. The first 4 bytes are an integer that tells how long the subsequent XML document is.

How would you write something that listens on a socket and can pick up and process a message like this?

What goes inside the while parentheses?

 
class Listener implements Runnable {
   Socket socket;
   Listener(Socket socket) {
      this.socket = socket;
   }
   public void run() {
      while(???) {
         ???
         System.out.println("Received XML" + xml);
      }
   }
}

[ June 15, 2005: Message edited by: Carl Bradbury ]