Shutting down the network loop

Hi there!

I'm trying to make a little chat server using Swing and NIO. I've got the main class based on JFrame, and a ServerBase object (based on the code from http://java.about.com/gi/dynamic/offsite.htm?zi=1/XJ&sdn=java&zu=http%3A%2F%2Fwww.owlmountain.com%2Ftutorials%2FNonBlockingIo.htm) that does all the networking jazz. The problem is that when I shut the main window, the program doesn't actually exit.

This is what the main networking method looks like:

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   public void acceptConnections() throws IOException, InterruptedException
   {
      SelectionKey acceptKey = selectableChannel.register( selector, SelectionKey.OP_ACCEPT );
      System.out.println( "Acceptor loop..." );
      while( ( keysAdded = acceptKey.selector().select() ) > 0 )
      {
         System.out.println( "Selector returned " + keysAdded + " ready for IO operations" );
         
         Set readyKeys = selector.selectedKeys();
         Iterator i = readyKeys.iterator();
         while( i.hasNext() )
         {
            SelectionKey key = (SelectionKey)i.next();
            i.remove();
            
            if( key.isAcceptable() )
            {
               ServerSocketChannel nextReady = (ServerSocketChannel)key.channel();
               System.out.println( "Processing selection key" +
                  " read=" + key.isReadable() +
                  " write=" + key.isWritable() +
                  " accept=" + key.isAcceptable()
                  );
               
               SocketChannel channel = nextReady.accept();
               channel.configureBlocking( false );
               SelectionKey readKey = channel.register( selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE );
               readKey.attach( new ChannelCallback( channel ) );
            }
            else if( key.isReadable() )
            {
               SelectableChannel nextReady = (SelectableChannel)key.channel();
               System.out.println( "Processing selection key" +
                  " read=" + key.isReadable() +
                  " write=" + key.isWritable() +
                  " accept=" + key.isAcceptable()
                  );
               
               readMessage( (ChannelCallback)key.attachment() );
            }
            else if( key.isWritable() )
            {
               ChannelCallback callback = (ChannelCallback)key.attachment();
               // Have to find a way to actually ... you know... do stuff.
               String message = "What is your name?";
               ByteBuffer buf = ByteBuffer.wrap( message.getBytes() );
               int nBytes = callback.getChannel().write( buf );
            }
         }
      }
      
      System.out.println( "End acceptor loop." );
   }

From what I can tell, it just sort of sits at the 'while( blah blah )' until it gets something over the network, right? But since I haven't written a client yet, that never happens. hehe

For that matter, how can I hook up an event handler of some sort to catch when the application is shutting down, so that I can clean all this up?

Thanks in advance~