code: void savePreviousActionInfo( ActionForm form, HttpServletRequest request, ActionMapping mapping,
                                   ServletContext servletContext )
      {
          //
          // If previous-action is disabled (unused in this pageflow), just return.
          //
          if ( isPreviousActionInfoDisabled() ) return;
          String actionURI = InternalUtils.getDecodedServletPath( request );
          _previousActionInfo = new PreviousActionInfo( form, actionURI, request.getQueryString() );
      }
docs: Called from {@link FlowController#execute}.