Programming Exercises: (From the Textbook) - 13.4 (Display Calender) Rewrite thePrintCalendar class in listing 6.12 (attached) to display a Calendar for a specified month using the Calendar and GregorianCalendar classes. (please refer to textbook for full figure 13.9 and problem description).

You can set a time represented in a Date object for the calendar by invoking calendar.setTime(date) and retrieve the time by invoking calendar.getTime().

13.9 Can you create a Calendar object using the Calendar class?

import java.util.Scanner; public class PrintCalendar { /** Main method */ public static void main(String[] args) { Scanner input = new Scanner(System.in); // Prompt the user to enter year System.out.print("Enter full year (e.g., 2001): "); int year = input.nextInt(); // Prompt the user to enter month System.out.print("Enter month in number between 1 and 12: "); int month = input.nextInt(); // Print calendar for the month of the year printMonth(year, month); } /** Print the calendar for a month in a year */ public static void printMonth(int year, int month) { // Print the headings of the calendar printMonthTitle(year, month); // Print the body of the calendar printMonthBody(year, month); } /** Print the month title, e.g., May, 1999 */ public static void printMonthTitle(int year, int month) { System.out.println(" " + getMonthName(month) + " " + year); System.out.println("-----------------------------"); System.out.println(" Sun Mon Tue Wed Thu Fri Sat"); } /** Get the English name for the month */ public static String getMonthName(int month) { String monthName = ""; switch (month) { case 1: monthName = "January"; break; case 2: monthName = "February"; break; case 3: monthName = "March"; break; case 4: monthName = "April"; break; case 5: monthName = "May"; break; case 6: monthName = "June"; break; case 7: monthName = "July"; break; case 8: monthName = "August"; break; case 9: monthName = "September"; break; case 10: monthName = "October"; break; case 11: monthName = "November"; break; case 12: monthName = "December"; } return monthName; } /** Print month body */ public static void printMonthBody(int year, int month) { // Get start day of the week for the first date in the month int startDay = getStartDay(year, month); // Get number of days in the month int numberOfDaysInMonth = getNumberOfDaysInMonth(year, month); // Pad space before the first day of the month int i = 0; for (i = 0; i < startDay; i++) System.out.print(" "); for (i = 1; i <= numberOfDaysInMonth; i++) { System.out.printf("%4d", i); if ((i + startDay) % 7 == 0) System.out.println(); } System.out.println(); } /** Get the start day of month/1/year */ public static int getStartDay(int year, int month) { final int START_DAY_FOR_JAN_1_1800 = 3; // Get total number of days from 1/1/1800 to month/1/year int totalNumberOfDays = getTotalNumberOfDays(year, month); // Return the start day for month/1/year return (totalNumberOfDays + START_DAY_FOR_JAN_1_1800) % 7; } /** Get the total number of days since January 1, 1800 */ public static int getTotalNumberOfDays(int year, int month) { int total = 0; // Get the total days from 1800 to 1/1/year for (int i = 1800; i < year; i++) if (isLeapYear(i)) total = total + 366; else total = total + 365; // Add days from Jan to the month prior to the calendar month for (int i = 1; i < month; i++) total = total + getNumberOfDaysInMonth(year, i); return total; } /** Get the number of days in a month */ public static int getNumberOfDaysInMonth(int year, int month) { if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) return 31; if (month == 4 || month == 6 || month == 9 || month == 11) return 30; if (month == 2) return isLeapYear(year) ? 29 : 28; return 0; // If month is incorrect } /** Determine if it is a leap year */ public static boolean isLeapYear(int year) { return year % 400 == 0 || (year % 4 == 0 && year % 100 != 0); } }