private int size(@Nullable Collection<?> collection) {
    return null == collection ? 0 : collection.size();
  }
@param service the name of the service
@param quickLink the quicklink
@return a boolean indicating whether the link in the parameter should be visible
ambari-server/src/main/java/org/apache/ambari/server/state/quicklinksprofile/DefaultQuickLinkVisibilityController.java