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.

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;
        }
    }

}

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.
```