class Duration implements Cloneable, Serializable, Comparable<Duration>, JAXBable<JAXBDuration> {

    public String toISO8601String()
    {
        return new StringBuilder().append(getISO8601Prefix()).append(formatForISO8601(getMagnitude()))
                .append(getISO8601Designator()).toString();
    }

    public  Duration(BigDecimal magnitude);
    protected  Duration(long unscaledMagnitude, int scale);

}