code: protected PresentationState getPresentationState(HttpServletRequest request) {
      String attrName = getPresentationAttrName();
  
      if ((attrName == null) ||
           (attrName.equals("NONE"))) {
        return null;
      }
  
      /* First try the request */
  
      Object o = request.getAttribute(attrName);
  
      if (o == null) {
        HttpSession sess = request.getSession(false);
  
        if (sess == null) {
          return null;
        }
  
        o = sess.getAttribute(attrName);
      }
  
      if (o == null) {
        return null;
      }
  
      PresentationState ps = (PresentationState)o;
  
      if (debug()) {
        ps.debugDump("ConfiguredXSLTFilter");
      }
  
      return ps;
    }
docs: Obtain the presentation state from the session. Override if you want
  different behaviour.
  
  @param request
  @return PresentationState