code: @CanIgnoreReturnValue
    public final StringBuilder appendTo(StringBuilder builder, Object[] parts) {
      return appendTo(builder, Arrays.asList(parts));
    }
docs: Appends the string representation of each of {@code parts}, using the previously configured
  separator between each, to {@code builder}. Identical to {@link #appendTo(Appendable,
  Iterable)}, except that it does not throw {@link IOException}.