HttpSessionAttributeListener vs HttpSessionBindingListenter

[ming zhu]

Hi,
Can someone please explain the difference between these two interfaces? When do I use them? I guess I do not understand the exact meaning of binding.
Thanks in advance.

[Andy Wong]

Hi,
This is a rephase of what I got from the SCWCD Exam Study Kit:
"Difference between HttpSessionAttributeListener and HttpSessionBindingListener is that HttpSessionAttributeListener is configured in the deployment descriptor and the container creates only one instance of the specified class. While HttpSessionBindingListener is not configured in the deployment descriptor. The servlet container calls methods on an object implementing this interface only if that object is added or removed from a session. While the HttpSessionAttributeListener interface is used to track the activity for all sessions on an application, the HttpSessionBindingListener interface is used to take actions when certain kinds of objects are added or removed from a session."
Thanks,
Andy

[ming zhu]

Thanks, Andy!