}
public Pair<Double, Double> convertDates(final Date optionDate, final Period swapTenor) {
final Date end = optionDate.add(swapTenor);
// TODO: code review :: please verify against QL/C++ code
QL.require(end.gt(optionDate) , "negative swap tenorgiven"); // QA:[RG]::verified // TODO: message
final double optionTime = timeFromReference(optionDate);
final double timeLength = dayCounter().yearFraction(optionDate, end);
return new Pair<Double, Double>(optionTime, timeLength);
}