code: AddIfCluster addIfCluster(Object... objects) {
      if (addIfCluster == null) {
        addIfCluster = new AddIfCluster(!getWebServer().isStandalone());
      }
      addIfCluster.ifAdd(objects);
      return addIfCluster;
    }
docs: Add a component to container only if clustering is enabled.
  
  @throws IllegalStateException if called from PlatformLevel1, when cluster settings are not loaded