The channel that this listener is observing.
Listener will trigger whenever a context is broadcast on this channel.
The handler for when this listener receives a context broadcast.
Unsubscribe the listener object. We will no longer receive context messages on this handler.
Calling this method has no effect if the listener has already been unsubscribed. To re-subscribe, call addContextListener again to create a new listener object.
Listener for context broadcasts coming from a specific channel. Generated by ChannelBase.addContextListener.