Topic Listener

To receive notifications for connect and disconnect events you can contribute a TopicListener via Tapestry IOC. A container may contain multiple pushTargets with multiple topics, in this case the TopicListener will receive connect and disconnect notifications for each unique topic.

eg:

/**
 * Leave the chat room when the client disconnects
 */
public class ChatTopicListener implements TopicListener {
   private static final Pattern ROOM_PATTERN = Pattern.compile("rooms/(.*)/messages");
   private final ChatManager chatManager;
   
   public ChatTopicListener(ChatManager chatManager) {
      super();
      this.chatManager = chatManager;
   }
   
   @Override
   public void onConnect(AtmosphereResource resource, String topic) {
   }
   
   @Override
   public void onDisconnect(AtmosphereResource resource, String topic) {
      Matcher matcher = ROOM_PATTERN.matcher(topic);
      if (matcher.matches()) {
         HttpSession session = resource.getRequest().getSession(false);
         if (session != null) {
            String chatUser = (String) session.getAttribute("CHAT_USER");
            if (chatUser != null) {
               String room = matcher.group(1);
               chatManager.leaveRoom(room, chatUser);
            }
         }
      }
   }
}

public class AppModule {
   public static void contributeTopicListener(OrderedConfiguration<TopicListener> config) {
      config.addInstance("chat", ChatTopicListener.class);
   }
}