HSJS Chapter-6 Question-15

[Peter Piddle]

Hi All,
I am solving mock from K&B from Chapter 6. The question asks

Which method(s) can be used to ask the container to notify your application whenever a session is about to timeout?
Options correct are A and C

A.HttpSessionListener.sessionDestroyed

C. HttpSessionBindingListener.valueUnBound

My question is the valueUnBound() method is related when an attribute is removed from the session, session might be existing that time.
Then why option C is made correct?

Thanks,

[Frits Walraven]

Hi Peter,

Then why option C is made correct?

According to the API:

Causes an object to be notified when it is bound to or unbound from a session. The object is notified by an HttpSessionBindingEvent object. This may be as a result of a servlet programmer explicitly unbinding an attribute from a session, due to a session being invalidated, or due to a session timing out.

Regards,
Frits