Package org.zkoss.zkmax.au.websocket

Class WebSocketServerPush

  • All Implemented Interfaces:
    ServerPush
    public class WebSocketServerPush
extends java.lang.Object
implements ServerPush
    A server-push implementation that is based on WebSocket. This is the default server-push class when WebSocket connection is enabled. To enable WebSocket connection, please refer to WebSocketWebAppInit for more information.
    Since:
    8.5.0
    Author:
    wenninghsu

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean activate​(long timeout)
      Activate the current thread (which must be a server-push thread).
      boolean deactivate​(boolean stop)
      Deactivates the current thread (which must be a server-push thread).
      boolean isActive()
      Returns if the working thread of the server push is active.
      void onPiggyback()
      Called when Events.ON_PIGGYBACK is received.
      void resume()
      Resumes server-push - this is required after desktop recycling.
      <T extends Event>
      void      		 schedule​(EventListener<T> listener, T event, Scheduler<T> scheduler)
      Called by the associated desktop to schedule a task to execute asynchronously.
      void setReady​(boolean ready)  
      protected void setWebSocketConnectionInfos​(WebSocketEndPoint webSocketEndpoint, javax.servlet.http.HttpServletRequest request)  
      void start​(Desktop desktop)
      Starts and initializes the server-push controller.
      protected void startClientPush()
      Sends an AU response to the client to start the server push.
      void stop()
      Stops and cleans up the server-push controller.
      protected void wakePending()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • WebSocketServerPush

        public WebSocketServerPush()

    • Method Detail

      • setReady

        public void setReady​(boolean ready)

      • setWebSocketConnectionInfos

        protected void setWebSocketConnectionInfos​(WebSocketEndPoint webSocketEndpoint,
                                           javax.servlet.http.HttpServletRequest request)

      • startClientPush

        protected void startClientPush()
        Sends an AU response to the client to start the server push. It is called by start(org.zkoss.zk.ui.Desktop).

        The derived class usually overrides this method to support different devices.

        The default implementation is to send an AuScript response.

      • schedule

        public <T extends Event> void schedule​(EventListener<T> listener,
                                       T event,
                                       Scheduler<T> scheduler)
        Description copied from interface: ServerPush
        Called by the associated desktop to schedule a task to execute asynchronously.

        The implementation usually delegates the scheduling to the scheduler passed as the third argument, which is controlled by the desktop. Of course, it could schedule it by itself.

        Specified by:
        schedule in interface ServerPush
        Parameters:
        listener - the task to execute
        event - the event to be passed to the task (i.e., the event listener). It could null or any instance as long as the task recognizes it.
        scheduler - the default scheduler to schedule the task. The implementation usually delegates the scheduling back to it. If you prefer to handle it by yourself, you could ignore it.

      • activate

        public boolean activate​(long timeout)
                 throws java.lang.InterruptedException,
                        DesktopUnavailableException
        Description copied from interface: ServerPush
        Activate the current thread (which must be a server-push thread). It causes the current thread to wait until the desktop is available to access, the desktop no longer exists, some other thread interrupts this thread, or a certain amount of real time has elapsed.

        The invoker of this method must invoke ServerPush.deactivate(boolean) in this finally clause.

        Note: the activation is applied to the desktop that was assigned by ServerPush.start(org.zkoss.zk.ui.Desktop).

        Unlike ServerPush.onPiggyback(), this method is NOT called in the context of an event listener. Rather, it is called in the thread of a server-push thread.

        Specified by:
        activate in interface ServerPush
        Parameters:
        timeout - the maximum time to wait in milliseconds. Ignored (i.e., never timeout) if non-positive.
        Returns:
        whether it is activated or it is timeout. The only reason it returns false is timeout.
        Throws:
        java.lang.InterruptedException - if it is interrupted by other thread
        DesktopUnavailableException - if the desktop is removed (when activating).

      • deactivate

        public boolean deactivate​(boolean stop)
        Description copied from interface: ServerPush
        Deactivates the current thread (which must be a server-push thread).
        Specified by:
        deactivate in interface ServerPush
        Parameters:
        stop - whether to stop after deactivate
        Returns:
        true if it is stopped
        See Also:
        ServerPush.activate(long)

      • wakePending

        protected void wakePending()

      • onPiggyback

        public void onPiggyback()
        Description copied from interface: ServerPush
        Called when Events.ON_PIGGYBACK is received. The invocation is passive (i.e., triggered by other events, rather than spontaneous).

        This method is called in the context of an event listener. In other words, the execution is activated and you can retrieve it by Executions.getCurrent().

        Specified by:
        onPiggyback in interface ServerPush