title: Filter for checking session existence
body: <p>I am developing a web application in Struts. I have a requirement that I have to check that a session exists for user. If the user session exists then user can access the resource, or I need to check session variable existence before accessing every JSP page.</p>
  
  <p>For that I make use of filter where I check for the session variable existence. But when I use filter, every request is routed to that filter--even the login page request is routed to filter. The login page doesn't need the filter check applied, what to do for this?</p>