//  File:  LeapYearTester2.java

//  Purpose:  Indicates whether or not a year - entered by the user - 
//            is a leap year.  A year is a leap year if either one of
//            the following is true:
//			  1.	the year is divisible by 4 and not by 100
//			  2.	the year is divisible by 400

//  Version 2 of the LeapYearTester class is identical to previous version,
//  except for the isLeapYear method, which has been simplified (maybe) and
//  shows how a method can have multiple return statements

import javax.swing.JOptionPane ;

/**
 * A class thats tests whether a given year is a leap year
 */
public class LeapYearTester2
{
	private int year ;	// 4-digit year being tested to see if it's a leap year
	
	/**
	 * Create a LeapYearTester object.
	 * @param inputYear the year being tested
	 * Precondition: inputYear >= 1583
	 */
	public LeapYearTester2 (int inputYear)
	{
		year = inputYear ;
	}
	
	/**
	 * Is a year a leap year?
	 * @return true if year is a leap year, false if not
	 */
	public boolean isLeapYear()
	{
   	if (year % 400 == 0)		// special "century" leap year (every 400 years)
   		return true ;   		                            

  		else if (year % 4 == 0 		// divisible by 4 but not by 100
  		              && 
  		         year % 100 != 0)	
   		return true ;   		                            

   	else
   		return false ; 			// neither of above, so not a leap year   		                            
 	}

	public static void main(String[] args)
	{
   		String input = JOptionPane.showInputDialog("Enter a 4-digit year") ;
   		
   		int inputYear = Integer.parseInt(input) ;
   		
   		LeapYearTester testYear = new LeapYearTester(inputYear) ;

   		// Is it a leap year?
	
   		if ( testYear.isLeapYear() )			// calls boolean method
   		{
				System.out.println(inputYear + " is a leap year.") ;
   		}
   		else
   		{
				System.out.println(inputYear + " is not a leap year.") ;
   		}
   	}
}

/* sample output:

2010 is not a leap year.

2012 is a leap year.

2100 is not a leap year.

2000 is a leap year.

*/

/*

BTW, here is the shortest possible version of method isLeapYear:

public boolean isLeapYear()
{
   return year % 4 == 0 && year % 100 != 0 || year % 400 == 0 ;
}

;-)

*/