A leap year is a 366-day year, which is one day longer than a normal year. This additional day comes is in February, where February is 29 days compared to the usual 28 days. Leap year comes in an interval of four years.
A year is leap year if the below conditions are satisfied:
- Year is multiple of 400.
- Year is multiple of 4 and not multiple of 100.
Example – Check a year is a leap year or not
public class LeapYear {
public static void isLeapYear(int year) {
if ((year % 400 == 0) || ((year % 4 == 0) && (year % 100 != 0))) {
System.out.println("Year " + year + " is a leap year");
} else {
System.out.println("Year " + year + " is not a leap year");
System.out.println();
}
}
public static void main(String[] args) {
LeapYear.isLeapYear(2012);
LeapYear.isLeapYear(2016);
LeapYear.isLeapYear(2020);
LeapYear.isLeapYear(2021);
}
}
Output
Year 2012 is a leap year Year 2016 is a leap year Year 2020 is a leap year Year 2021 is not a leap year
Example – Check a year is a leap year or not using Java library method
The calendar class has a utility method that returns the maximum number of days in a year that you can use to check if it is less than 365.
import java.util.Calendar;
public class LeapYear {
public static void isLeapYear(int year) {
boolean result = false;
Calendar cal = Calendar.getInstance();
cal.set(Calendar.YEAR, year); // setting year in to calendar
int noOfDays = cal.getActualMaximum(Calendar.DAY_OF_YEAR);
if (noOfDays > 365) {
result = true;
}
if (result) {
System.out.println("Year " + year + " is a leap year");
} else {
System.out.println("Year " + year + " is not a leap year");
System.out.println();
}
}
public static void main(String[] args) {
LeapYear.isLeapYear(2012);
LeapYear.isLeapYear(2016);
LeapYear.isLeapYear(2020);
LeapYear.isLeapYear(2021);
}
}
Output
Year 2012 is a leap year Year 2016 is a leap year Year 2020 is a leap year Year 2021 is not a leap year
