long upper = Math.round(r.getUpperBound());
            long lower = Math.round(r.getLowerBound());
            this.first = createInstance(this.autoRangeTimePeriodClass, 
                    new Date(lower), this.timeZone);
            this.last = createInstance(this.autoRangeTimePeriodClass, 
                    new Date(upper), this.timeZone);