code: private String calculateSearchLaunchUrl(RenderRequest request, RenderResponse response) {
          final HttpServletRequest httpRequest =
                  this.portalRequestUtils.getPortletHttpRequest(request);
          final IPortalUrlBuilder portalUrlBuilder =
                  this.portalUrlProvider.getPortalUrlBuilderByPortletFName(
                          httpRequest, "search", UrlType.ACTION);
          return portalUrlBuilder.getUrlString();
      }
docs: Create an actionUrl for the indicated portlet The resource URL is for the ajax typing search
  results response.
  
  @param request render request
  @param response render response