private int year
private int month
private int date

• April, June, September, November have 30 days
• February has 28 days, except in leap years it has 29 days
• All other months have 31 days
• Leap years are divisible by 4, except after 1582, years divisible by 100 but not 400 are not leap years
• There is no year 0; year 1 is preceded by year -1
• In the switchover to the Gregorian calendar, ten days were dropped: October 15, 1582 is preceded by October 4