code: public void destroy( HttpServletRequest request )
      {
          StorageHandler sh = Handlers.get( getServletContext() ).getStorageHandler();
          HttpServletRequest unwrappedRequest = PageFlowUtils.unwrapMultipart( request );
          RequestContext rc = new RequestContext( unwrappedRequest, null );
          String attrName = ScopedServletUtils.getScopedSessionAttrName( JPF_STACK_ATTR, unwrappedRequest );
          
          sh.removeAttribute( rc, attrName );
      }
docs: Destroy the stack of {@link PageFlowController}s that have invoked nested page flows.
  
  @param request the current HttpServletRequest.