CheckSessionExpiration checks the session associated with the request to see whether the it has expired and when it has, what caused the expiration. By examining the sessionRestored parameter of the Oracle ATG Web Commerce request, CheckSessionExpiration can determine if the session ended because of a server failure. When an Oracle ATG Web Commerce server fails during a request, a second Oracle ATG Web Commerce server creates a new session, retrieves information about the first session from the backup server, and changes the sessionRestored parameter from null to the original session ID to indicate that the session ID is invalid. CheckSessionExpiration reads sessionRestored and halts the request, if sessionRestored indicates it is been superseded by another request. Otherwise, CheckSessionExpiration assumes the session was ended due to an expired cookie; in that case it redirects the user to the URL provided in its URLExpiration property.

This servlet is used only by the Motorprise Reference Application. For information on how CheckSessionExpiration its use, see the ATG Business Commerce Reference Application Guide.