Tutorial:Listeners
From Wesip
From Wesip
The following SIP specific listener interfaces exist:
- - javax.servlet.sip.SipApplicationSessionListener: Invoked whenever a SipApplicationSession is created, destroyed or has timed out.
- - javax.servlet.sip.SipSessionListener: Notified when a SipSession is created or destroyed.
- - javax.servlet.sip.SipSessionAttributeListener: Invoked when attributes are added, replaced or removed from the context.
- - javax.servlet.sip.SipErrorListener: Called upon loss of an expected ACK or PRACK.
- - javax.servlet.sip.TimerListener: Used to track expiration of Timers
All of them are declared in the SIP application deployment descriptor sip.xml using the listener tag.
Other two kinds of listeners are:
- - javax.servlet.sip.SipSessionBindingListener: Used for notification of attribute binding and unbinding.
- - javax.servlet.sip.SipSessionActivationListener: Notification of session activation or passivation.
Those listeners aren't declared in the deployment descriptor but simply stored as attributes of the SipSession they are supposed to monitor.