"Type error: cannot cast xs:duration to "
"Type error: cannot cast ' + Type.getTypeName(getType()) 'to "
	public AtomicValue convertTo(int requiredType) throws XPathException {		switch(requiredType) {			case Type.ITEM:			case Type.ATOMIC:			case Type.DURATION:				return this;			case Type.YEAR_MONTH_DURATION:				if (duration.getField(DatatypeConstants.YEARS) != null || 					duration.getField(DatatypeConstants.MONTHS) != null)					return new YearMonthDurationValue(TimeUtils.getInstance().newDurationYearMonth(						duration.getSign() >= 0,						(BigInteger) duration.getField(DatatypeConstants.YEARS),						(BigInteger) duration.getField(DatatypeConstants.MONTHS)));				else 					return new YearMonthDurationValue(YearMonthDurationValue.CANONICAL_ZERO_DURATION);			case Type.DAY_TIME_DURATION:				return new DayTimeDurationValue(TimeUtils.getInstance().newDuration(					duration.getSign() >= 0,					null,					null,					(BigInteger) duration.getField(DatatypeConstants.DAYS),					(BigInteger) duration.getField(DatatypeConstants.HOURS),					(BigInteger) duration.getField(DatatypeConstants.MINUTES),					(BigDecimal) duration.getField(DatatypeConstants.SECONDS)));			case Type.STRING:				return new StringValue(getStringValue());			case Type.UNTYPED_ATOMIC :				return new UntypedAtomicValue(getStringValue());			default:				throw new XPathException(					"Type error: cannot cast xs:duration to "					+ Type.getTypeName(requiredType));		}	}