public class MyPeriod { private int length; public String toString() { return "Periode : " + length + " jour" + (length > 1 ? "s" : ""); } public void addDay() { this.length += 1; } public MyPeriod(MyDate date1, MyDate date2) { if (date1.isEqual(date2)) { this.length = 0; return; } //Très dangereux et inefficace, ne faites pas ca svp. while (!date1.isEqual(date2)) { date1 = date1.tomorrow(); length++; } } public MyPeriod(int length) { this.length = length; } }