Maintain Session

[aakash bhatt]

If HTTP is staleless protocol then how does it maintain Session through HttpSession

Thanks,
aakash

[Ben Souther]

The server uses a session cookie (stored in the user's browser), or, sometimes a url parameter to match the user up to a session object (stored in memory on the server).

[aakash bhatt]

Thanks Ben,
With cookie and Url paramter we can maintain session indirectly.
But my query is as Http is a staless protocol then how does we can maintain a sesion by setting values in HttpSession, then how does in this HTTP protcol handle it.

Thanks,
aakash

[Ben Souther]

Yes, HTTP is stateless. That means the server has to check for a sessionId in every request that comes in (either as a cookie header or as a url parameter).
If it finds one, it checks to see if there is an object, stored in session, with a matching id. If not, then it creates a new object and sends the ID back to the browser in the response.

The HTTP protocol doesn't handle it. The servlet container mimicks a stateful session with this technique.

If you're asking how to save objects in session, read up on the HttpSession's
getAttribute and setAttribute methods.
http://java.sun.com/j2ee/1.4/docs/api/javax/servlet/http/HttpSession.html