Key methods of HttpSession

getCreationTime()
Returns the time the
session was first created.

getLastAccessedTime()
Returns the last time the
Container got a request
with this session ID (in
milliseconds).

setMaxInactiveInterval()
Specifies the maximum
time, in seconds, that you
want to allow between client
requests for this session.

getMaxInactiveInterval()
Returns the maximum time,
in seconds, that is allowed
between client requests for
this session.

invalidate()
Ends the session. This
includes unbinding all
session attributes currently
stored in this session. (More
on that later in this chapter.)