Web Socket GIST ( JAVA CODE)

public class SocketServlet extends WebSocketServlet {
    
  private static final long serialVersionUID = 1L;
	
	private static final String GUEST_PREFIX = "Guest";
	
	private final AtomicInteger connectionIds = new AtomicInteger(0);
	
	private final Set<ChatMessageInbound> connections =
            new CopyOnWriteArraySet<ChatMessageInbound>();
	
    public SocketServlet() {
        super();
    }

    @Override
    protected StreamInbound createWebSocketInbound(String arg0, HttpServletRequest arg1) {
        return new ChatMessageInbound(connectionIds.incrementAndGet());
    }
    
    private final class ChatMessageInbound extends MessageInbound
    {

        private final String nickname;
        
        private ChatMessageInbound(int id)
        {
            this.nickname=GUEST_PREFIX +id;
        }
        
        @Override
        protected void onBinaryMessage(ByteBuffer arg0) throws IOException {
            throw new UnsupportedOperationException(
                    "Binary message not supported.");
        }

        @Override
        protected void onTextMessage(CharBuffer arg0) throws IOException {
            String message=String.format("%s : %s",nickname,arg0.toString());
            broadcast(message);
        }

        @Override
        protected void onClose(int status) {
            connections.remove(this);
            String message=String.format("%s %s",nickname," left the chat");
            broadcast(message);
        }

        @Override
        protected void onOpen(WsOutbound outbound) {
            connections.add(this);
            String message=String.format("%s %s", nickname," has joined");
            broadcast(message);
        }
        
        private void broadcast(String message)
        {
            for(ChatMessageInbound connection:connections)
            {
                try
                {
                    CharBuffer buff=CharBuffer.wrap(message);
                    connection.getWsOutbound().writeTextMessage(buff);
                }
                catch(IOException ex)
                {
                    ex.printStackTrace();
                }
            }
        }
        
    }

}