def setYear(self, year):
        if year == 0:
            raise NormalDateException('cannot set year to zero')
        elif year < -9999:
            raise NormalDateException('year cannot be less than -9999')
        elif year > 9999:
            raise NormalDateException('year cannot be greater than 9999')
        (y, m, d) = self.toTuple()
        self.setNormalDate((year, m, d))