public static QuickLinkVisibilityController get(@Nullable String quickLinkProfileJson) {
    if (null == quickLinkProfileJson) {
      LOG.info("No quick link profile is set, will display all quicklinks.");
      return new ShowAllLinksVisibilityController();
    }
    try {
      QuickLinksProfile profile = new QuickLinksProfileParser().parse(quickLinkProfileJson.getBytes());
      return new DefaultQuickLinkVisibilityController(profile);
    }
    catch (IOException | QuickLinksProfileEvaluationException ex) {
      LOG.error("Unable to parse quick link profile json: " + quickLinkProfileJson, ex);
      return new ShowAllLinksVisibilityController();
    }
  }
@param quickLinkProfileJson the quick links profile or {@code null} if no profile is set
@return a {@link DefaultQuickLinkVisibilityController} if the profile exists and is valid, {@link ShowAllLinksVisibilityController}
  otherwise.
ambari-server/src/main/java/org/apache/ambari/server/state/quicklinksprofile/QuickLinkVisibilityControllerFactory.java