JavaEE Session Listeners

The JavaEE specification defines some listeners that can be used to monitoring the session activity. Specifically there are three of them although one was just created in the last version 7:

• javax.servlet.http.HttpSessionListener: A listener for monitoring session lifecycle (session creation and destruction).
• javax.servlet.http.HttpSessionAttributeListener: A listener for monitoring attribute changes (when an attribute is added, modified or deleted from the session).
• javax.servlet.http.HttpSessionIdListener: A listener for monitoring session id changes, this listener is new in JavaEE 7 and it was created because now it is possible to change the session id programmatically is order to avoid Session fixation attacks.