package com.acme;
   
   import java.io.IOException;
   import java.util.Set;
   import java.util.concurrent.CopyOnWriteArraySet;
   
   import javax.servlet.RequestDispatcher;
   import javax.servlet.http.HttpServletRequest;
   import javax.servlet.http.HttpServletResponse;
  
  import org.eclipse.jetty.util.TypeUtil;
  import org.eclipse.jetty.util.log.Log;
  import org.eclipse.jetty.util.log.Logger;
  import org.eclipse.jetty.websocket.WebSocket;
  import org.eclipse.jetty.websocket.WebSocketServlet;
  
  public class WebSocketChatServlet extends WebSocketServlet
  {
      private static final Logger LOG = Log.getLogger(WebSocketChatServlet.class);
  
      private final Set<ChatWebSocket> _members = new CopyOnWriteArraySet<ChatWebSocket>();
      
      @Override
      protected void doGet(HttpServletRequest request, HttpServletResponse response) 
          throws javax.servlet.ServletException ,IOException 
      {
          getServletContext().getNamedDispatcher("default").forward(request,response);
      };
      
      public WebSocket doWebSocketConnect(HttpServletRequest request, String protocol)
      {
          return new ChatWebSocket();
      }
      
      /* ------------------------------------------------------------ */
      /* ------------------------------------------------------------ */
      class ChatWebSocket implements WebSocket.OnTextMessage
      {
          Connection _connection;
  
          public void onOpen(Connection connection)
          {
              // LOG.info(this+" onConnect");
              _connection=connection;
              _members.add(this);
          }
          
          public void onMessage(byte frame, byte[] data,int offset, int length)
          {
              // LOG.info(this+" onMessage: "+TypeUtil.toHexString(data,offset,length));
          }
  
          public void onMessage(String data)
          {
              if (data.indexOf("disconnect")>=0)
                  _connection.disconnect();
              else
              {
                  // LOG.info(this+" onMessage: "+data);
                  for (ChatWebSocket member : _members)
                  {
                      try
                      {
                          member._connection.sendMessage(data);
                      }
                      catch(IOException e)
                      {
                          LOG.warn(e);
                      }
                  }
              }
          }
          
          public void onClose(int code, String message)
          {
              // LOG.info(this+" onDisconnect");
              _members.remove(this);
          }
  
      }
  }