@Override
@SuppressWarnings("unchecked")
public void init(ServletConfig config) throws ServletException
{
  //  JdkOverLog4j.install();
    System.out.println("Init............");
    super.init(config);

    of("/chat").on(new ConnectionListener()
    {
        @Override
        public void onConnect(final Socket socket)
        {
            try
            {
                socket.emit(WELCOME, "Welcome to Socket.IO Chat, " + socket.getRequest().getRemoteAddr() + "!");

                socket.join("room");
            }
            catch (SocketIOException e)
            {
                e.printStackTrace();
                socket.disconnect(true);
            }

            socket.on(new DisconnectListener() {

                @Override
                public void onDisconnect(Socket socket, DisconnectReason reason, String errorMessage)
                {
                    of("/chat").emit(ANNOUNCEMENT, socket.getSession().getSessionId() + " disconnected");
                }
            });

            socket.on(CHAT_MESSAGE, new EventListener()
            {
                @Override
                public Object onEvent(String name, Object[] args, boolean ackRequested)
                {
                    System.out.println("Received chat message: " + args[0]);

                    try
                    {
                        socket.broadcast("room", CHAT_MESSAGE, socket.getId(), args[0]);
                    }
                    catch (SocketIOException e)
                    {
                        e.printStackTrace();
                    }

                    return "OK"; //this object will be sent back to the client in ACK packet
                }
            });

            socket.on(FORCE_DISCONNECT, new EventListener()
            {
                @Override
                public Object onEvent(String name, Object[] args, boolean ackRequested)
                {
                    socket.disconnect(false);
                    return null;
                }
            });

            socket.on(CLIENT_BINARY, new EventListener()
            {
                @Override
                public Object onEvent(String name, Object[] args, boolean ackRequested)
                {
                    Map map = (Map<Object, Object>)args[0];
                    InputStream is = (InputStream) map.get("buffer");
                    ByteArrayOutputStream os = new ByteArrayOutputStream();
                    try
                    {
                        ByteStreams.copy(is, os);
                        byte []array = os.toByteArray();
                        String s = "[";
                        for (byte b : array)
                            s += " " + b;
                        s += " ]";
                        System.out.println("Binary received: " + s);
                    }
                    catch (IOException e)
                    {
                        e.printStackTrace();
                    }

                    return "OK";
                }
            });

            socket.on(SERVER_BINARY, new EventListener()
            {
                @Override
                public Object onEvent(String name, Object[] args, boolean ackRequested)
                {
                    try
                    {
                        socket.emit(SERVER_BINARY,
                                new ByteArrayInputStream(new byte[] {1, 2, 3, 4}),
                                new ACKListener()
                                {
                                    @Override
                                    public void onACK(Object[] args)
                                    {
                                        System.out.println("ACK received: " + args[0]);
                                    }
                                });
                    }
                    catch (SocketIOException e)
                    {
                        socket.disconnect(true);
                    }

                    return null;
                }
            });
        }
    });
}

<servlet-name>Test</servlet-name>
<servlet-class>test.Test</servlet-class>

<servlet-name>Test</servlet-name>
<url-pattern>/socket.io/*</url-pattern>