Assignemnt #92 Weekday Calc

Code

///Name:JJ Deng
    ///Period: 6
    ///Program Name: Weekday Calc
    ///File Name: Weekday.java
    ///Date Finished: 3/20/16 
import java.util.Scanner;

public class Weekday
{
	public static void main( String[] args )
	{
		Scanner keyboard = new Scanner(System.in);

		System.out.println("Welcome to Mr. Davis's fantastic birth-o-meter!");
		System.out.println();
		System.out.println("All you have to do is enter your birth date, and it will tell you the day of the week on which you were born.");
		System.out.println();
		System.out.println("Some automatic tests....");
		System.out.println("12 10 2003 => " + weekday(12,10,2003));
		System.out.println(" 2 13 1976 => " + weekday(2,13,1976));
		System.out.println(" 2 13 1977 => " + weekday(2,13,1977));
		System.out.println(" 7  2 1974 => " + weekday(7,2,1974));
		System.out.println(" 1 15 2003 => " + weekday(1,15,2003));
		System.out.println("10 13 2000 => " + weekday(10,13,2000));
		System.out.println();

		System.out.println("Now it's your turn!  What's your birthday?");
		System.out.print("Birth date (mm dd yyyy): ");
		int mm = keyboard.nextInt();
		int dd = keyboard.nextInt();
		int yyyy = keyboard.nextInt();

		
		System.out.println("You were born on " + weekday(mm, dd, yyyy));
	}


	public static String weekday( int mm, int dd, int yyyy )
	{
		int yy, total;
		String date = "";
        
        yy = yyyy-1900;
        total = yy / 4;
        total = total + yy;
        total = total + dd;
        total = total + monthOffset(mm);
        
        if ( isLeap(yyyy) == true && mm == 1 || mm == 2 )
        {
            total --;
        }
        
        int remain = total % 7;
        
        date = weekdayname(remain) + ", " + month_name(mm) + ", " + yyyy;

		return date;
	}


	public static String month_name( int month )
	{
		String result;
		
        if (month == 1 )
        {
            result = "January";
        }
        else if ( month == 2)
        {
            result = "February";
        }
        else if ( month == 3)
        {
            result = "March";
        }
        else if ( month == 4)
        {
            result = "April";
        }
        else if ( month == 5)
        {
            result = "May";
        }
        else if ( month == 6) 
        {
            result = "June";
        }
        else if ( month == 7 )
        {
            result = "July";
        }
        else if ( month == 8)
        {
            result = "August";
        }
        else if ( month == 9 )
        {
            result = "September";
        }
        else if ( month == 10 )
        {
            result = "October";
        }
        else if ( month == 11 )
        {
            result = "November";
        }
        else if ( month == 12 )
        {
            result = "December";
        }
        else 
        {
            result = "ERROR";
        }
        
        
		return result;
        
	}
    public static int monthOffset( int month )
	{
		int result;
        
        if (month == 1)
        {
            result = 1;
        }
        else if (month == 2)
        {
            result = 4;
        }
        else if (month == 3)
        {
            result = 4;
        }
        else if (month == 4)
        {
            result = 0;
        }
        else if (month == 5)
        {
            result = 2;
        }
        else if (month == 6)
        {
            result = 5;
        }
        else if (month == 7)
        {
            result = 0;
        }
        else if (month == 8)
        {
            result = 3;
        }
        else if (month == 9)
        {
            result = 6;
        }
        else if (month == 10)
        {
            result = 1;
        }
        else if (month == 11)
        {
            result =  4;
        }
        else if (month == 12)
        {
            result = 6;
        }
        else
        {
            result = -1;
        }
		return result;
	}
     public static String weekdayname( int remain )
            {
                String result;
                
                if (remain == 1)
                    result = "Sunday";
                else if (remain == 2)
                    result = "Monday";
                else if (remain == 3)
                    result = "Tuesday";
                else if (remain == 4)
                    result = "Wednesday";
                else if (remain == 5)
                    result = "Thursday";
                else if (remain == 6)
                    result = "Friday";
                else if (remain == 7)
                    result = "Satruday";
                else
                    result = "ERROR";
                    
                return result;
            }

		
	public static boolean isLeap( int year )
	{
		// years which are evenly divisible by 4 are leap years,
		// but years divisible by 100 are not leap years,
		// though years divisible by 400 are leap years
		boolean result;

		if ( year%400 == 0 )
			result = true;
		else if ( year%100 == 0 )
			result = false;
		else if ( year%4 == 0 )
			result = true;
		else
			result = false;
		
		return result;
	}
}


  

Picture of the output