Classic example of a simple server:

class ThreadPerTaskSocketServer {
   public static void main(String[] args) throws IOException {
      ServerSocket socket = new ServerSocket(80);
      while (true) {
          final Socket connection = socket.accept();
          Runnable task = new Runnable() {
              public void run() {
                 handleRequest(connection);
              }
          };
          new Thread(task).start();
      }
   }
}

Why should the Socket be declared as final? Is it because the new Thread that handles the request could refer back to the socket variable in the method and cause some sort of ConcurrentModificationException?