/** Initialize the session attributes. */
 public void initializeSession() {
   ApplicationSessionInitializer asi = getApplicationSessionInitializer();
   if (asi != null) {
     asi.initializeSession();
     Map<String, Object> sessionAttributes = asi.getSessionAttributes();
     if (sessionAttributes != null) {
       setSessionAttributes(sessionAttributes);
     }
     propertyChangeSupport.firePropertyChange(SESSION_ATTRIBUTES, null, sessionAttributes);
   }
 }