Java program to check leap year

• A century year is a year ending with 00.  A century year is a leap year only if it is divisible by 400.
• A leap year (except a century year) can be identified if it is exactly divisible by 4.
• A century year should be divisible by 4 and 100 both.
• A non-century year should be divisible only by 4.

• Program:

public class Main {

  public static void main(String[] args) {

    // year to be checked
    int year = 2011;
    boolean leap = false;

    // if the year is divided by 4
    if (year % 4 == 0) {

      // if the year is century
      if (year % 100 == 0) {

        // if year is divided by 400
        // then it is a leap year
        if (year % 400 == 0)
          leap = true;
        else
          leap = false;
      }
      
      // if the year is not century
      else
        leap = true;
    }
    
    else
      leap = false;

    if (leap)
      System.out.println(year + " is a leap year.");
    else
      System.out.println(year + " is not a leap year.");
  }
}

• Output:

2011 is not a leap year

--- Another example ---

2012 is a leap year