Regarding Listener Concept

[yekkala krishna]

Hi,

I am following Hanumant Deshmukh material for preparation of SCWCD Exam.I have small query regarding the following question.Actually when any object is added to a session HttpSessionBindingListener will notify.but they are saying HttpSessionAttributeListener will call. Can Anybody explain clearly regarding the below question?

Which interface must a class implement so that instances of the class are
notified after any object is added to a session?
A. javax.servlet.http.HttpSessionListener
B. javax.servlet.http.HttpSessionValueListener
C. javax.servlet.http.HttpSessionBindingListener
D. javax.servlet.http.HttpSessionAttributeListener
Answer: D

With Regards,
Rama Krishna.Y

[Ankit Garg]

The question is asking about "any object" added to session. if your class implements HttpSessionBindingListener, then it will be notified when instances of that class are added to the session. A class that implements HttpSessionAttributeListener is notified when an instance of any object is added to the session...