* Calendar class 
{{{
public class Calendar {
    public static void main(String[] args) {
        System.out.println("Input year pleas : ex) 2013");
        System.out.print(">> ");

        Scanner scanner = new Scanner(System.in);
        int year = Integer.parseInt(scanner.nextLine());

        new Year(year).print();
    }
}
}}}
 *Month class
{{{
public class Month {
    private int month;
    private int length;
    private int startDate; // 1:mon 2:tue 3:wed 4:thu 5:fri 6 :sat 0:sun

    public Month(int month, int length, int startDate) {
        this.month = month;
        this.length = length;
        this.startDate = startDate;
    }

    public void print() {
        System.out.println("MONTH : " + month);
        System.out.println("sun\tmon\ttue\twed\tthu\tfri\tsat");

        String days = "";

        for (int i = 1; i <= startDate; i++) {
            days += "\t";
        }

        for (int i = 1; i <= length; i++) {
            days += i;
            days += ((i + startDate) % 7 == 0 ? "\n" : "\t");
        }

        System.out.println(days + "\n");
    }
}
}}}
 *Year class
{{{
public class Year {
    private int year;
    private List<Month> months;

    public Year(int year) {
        this.year = year;
        setMonths();
    }

    private void setMonths() {
        months = MonthFactory.getMonths(year);
    }

    public void print() {
        System.out.println("THIS YEAR IS : " + year + "\n\n");

        for (Month m : months) {
            m.print();
        }
    }
}
}}}
 * MonthFactory
{{{
public class MonthFactory {
    public static List<Month> getMonths(int year) {
        List<Month> months = new ArrayList();

        for (int i = 1; i <= 12; i++) {
            months.add(new Month(i, getDaysOfMonth(year, i), getStartDate(year, i)));
        }

        return months;
    }

    public static int getDaysOfYear(int year) {
        return isLeap(year) ? 366 : 365;
    }

    public static int getDaysOfMonth(int year, int month) {
        switch (month) {
            case 1: case 3: case 5: 
            case 7: case 8: case 10: case 12:
                return 31;
            case 4: case 6: case 9: case 11:
                return 30;
            case 2:
                return (isLeap(year) ? 29 : 28);
            default:
                return 0;
        }
    }

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

    public static int getStartDate(int year, int month) {
        int totalDays = 0;

        for (int i = 1; i < year; i++) {    // add days of years
            totalDays += getDaysOfYear(i);
        }

        for (int i = 1; i < month; i++) {   // add days of months
            totalDays += getDaysOfMonth(year, i);
        }

        return (totalDays + 1) % 7;   // +1 for sunday
    }
}
}}}