/**
  * @param mapping ActionMapping
  * @param formIn ActionForm
  * @param request ServletRequest
  * @param response ServletResponse
  * @return The ActionForward to go to next.
  */
 public ActionForward processUnsubscribe(
     ActionMapping mapping,
     ActionForm formIn,
     HttpServletRequest request,
     HttpServletResponse response) {
   Map params = makeParamMap(formIn, request);
   operateOnSelectedSet(mapping, formIn, request, response, "unsubscribeSystems");
   RequestContext requestContext = new RequestContext(request);
   ConfigActionHelper.clearRhnSets(requestContext.getCurrentUser());
   return getStrutsDelegate().forwardParams(mapping.findForward("success"), params);
 }