Java Check Leap Year Example

This example will tell you how to check whether a year is a leap year or not. As we know, leap year is an integer that can be divided by 4 but can not be divided by 100. For example, 1996 is just a leap year while 1900 is not. But if a year can be divided by 400, it is also a leap year.

1. Java Check Leap Year Example.

1. CheckLeapYear.java

   package com.dev2qa.java.basic;
   
   import java.util.Scanner;
   
   public class CheckLeapYear {
   
       public static void main(String[] args) {
   
           // Wrap command line console input to a Scanner object.
           Scanner scanner = new Scanner(System.in);
   
           System.out.println("Please input a year.");
   
           while(true)
           {
               // Get user input year string value.
               String year = scanner.nextLine();
   
               if("quit".equalsIgnoreCase(year))
               {
                   System.out.println("Program exit.");
                   break;
               }else
               {
                   long yearLong = getLong(year);
   
                   if(yearLong > -1)
                   {
                       if(((yearLong % 4 == 0) && (yearLong % 100 != 0)) || yearLong % 400 == 0)
                       {
                           System.out.println(year + " is a leap year. ");
                       }else
                       {
                           System.out.println(year + " is not a leap year. ");
                       }
                   }
               }
           }
       }
   
       /* Get long value of input string. */
       private static long getLong(String value)
       {
           long ret = -1;
   
           try {
               ret = Long.parseLong(value);
           }catch(NumberFormatException ex)
           {
               System.err.println("The input text is not a number.");
           }finally
           {
               return ret;
           }
       }
   
   }

2. When running the above code, it will prompt you to input a year value. If the value is not a number then it will print out an error message. Otherwise, it will print out related messages to show whether the year is a leap year or not.

   Please input a year.
   
   qqqq
   The input text is not a number.
   
   1996
   1996 is a leap year.
   
   1900
   1900 is not a leap year.
   
   2000
   2000 is a leap year.