org.wicketstuff.push.cometd
Class CometdService

java.lang.Object
  org.wicketstuff.push.cometd.CometdService

All Implemented Interfaces:

IChannelService

public class CometdService
extends java.lang.Object
implements IChannelService

Cometd based implementation of IChannelService.

This service is based on cometd client implemented by the dojo toolkit, which must be embedded in your application.

This implementation relies on cometd for updating the page, but actually uses regular cometd events, which, if a channel listener is properly installed on a component of the page using addChannelListener(Component, String, IChannelListener), will trigger a wicket ajax call to get the page actually refreshed using regular wicket ajax mechanisms.

This mean that each time an event is published, a new connection is made to the server to get the actual page update required by the IChannelListener.

Author:

Xavier Hanin, Rodolfo Hansen

See Also:

IChannelService

Field Summary

static java.lang.String

BAYEUX_CLIENT_PREFIX

Constructor Summary

CometdService(org.apache.wicket.protocol.http.WebApplication application)

Method Summary

void	addChannelListener(org.apache.wicket.Component component, java.lang.String channel, IChannelListener listener) Adds a behavior to the given component so that it will be notified of ChannelEvents.
void	addChannelRemoveListener(java.lang.String chnl, org.cometd.RemoveListener listener)
void	addChannelRemoveListener(java.lang.String chnl, org.cometd.RemoveListener listener, org.apache.wicket.Session sess) Cometd Specific method to Listen for client removals
org.apache.wicket.Application	getApplication()
void	publish(ChannelEvent event) Implementation of IChannelService.publish(ChannelEvent), which actually sends a cometd event to the client with a "proxy" attribute set to "true", which in turn triggers a wicket ajax call to get the listener notified and update the page.

Methods inherited from class java.lang.Object

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

Field Detail

BAYEUX_CLIENT_PREFIX

public static final java.lang.String BAYEUX_CLIENT_PREFIX

See Also:

Constant Field Values

Constructor Detail

CometdService

public CometdService(org.apache.wicket.protocol.http.WebApplication application)

Method Detail

addChannelListener

public void addChannelListener(org.apache.wicket.Component component,
                               java.lang.String channel,
                               IChannelListener listener)

Description copied from interface: IChannelService

Adds a behavior to the given component so that it will be notified of ChannelEvents.

Usually the component if a Page, even if it's not mandatory. Indeed the components reacting to the event are defined in the IChannelListener, by calling IChannelTarget methods. Hence any component on the page can serve as the host of the behavior, as soon as it is visible.

Specified by:

addChannelListener in interface IChannelService

Parameters:

component - the component to which the behavior should be added

channel - the channel for which the listener should be notified

listener - the IChannelListener which should be notified of ChannelEvents

addChannelRemoveListener

public void addChannelRemoveListener(java.lang.String chnl,
                                     org.cometd.RemoveListener listener,
                                     org.apache.wicket.Session sess)

Cometd Specific method to Listen for client removals

Parameters:

channel -

listener -

sess - Wicket Session you wish to associate with the listener.

addChannelRemoveListener

public void addChannelRemoveListener(java.lang.String chnl,
                                     org.cometd.RemoveListener listener)

See Also:

addChannelRemoveListener(String, RemoveListener, Session)

publish

public void publish(ChannelEvent event)

Implementation of IChannelService.publish(ChannelEvent), which actually sends a cometd event to the client with a "proxy" attribute set to "true", which in turn triggers a wicket ajax call to get the listener notified and update the page.

Specified by:

publish in interface IChannelService

Parameters:

event - the event to publish to the listeners

getApplication

public org.apache.wicket.Application getApplication()