@CheckForNull String name;
      @CheckForNull Object value;
      @CheckForNull ValueHolder next;
    }

    /**
     * Holder object for values that cannot be null or empty (will be printed unconditionally). This
     * helps to shortcut most calls to isEmpty(), which is important because the check for emptiness
     * is relatively expensive. Use a subtype so this also doesn't need any extra storage.
     */

      @CheckForNull String name;
      @CheckForNull Object value;
      @CheckForNull ValueHolder next;
    }

    /**
     * Holder object for values that cannot be null or empty (will be printed unconditionally). This
     * helps to shortcut most calls to isEmpty(), which is important because the check for emptiness
     * is relatively expensive. Use a subtype so this also doesn't need any extra storage.
     */