exercise3_33.java

Introduction to java programming 一书中所有编程练习部分的源码

// Exercise3_33.java
import javax.swing.*;

public class Exercise3_33 {
    public static void main(String[] args) {
        // Prompt the user to enter input
        String yearString = JOptionPane.showInputDialog("Enter a year:");
        int year = Integer.parseInt(yearString);
        
        String firstDayString = JOptionPane.showInputDialog("Enter the first day of the year:");
        int firstDay = Integer.parseInt(firstDayString);
        
        int numberOfDaysInMonth = 0;
        
        // Display calendar for each month
        for (int month = 1; month <= 12; month++) {
            // Display Calendar title
            switch (month) {
                case 1: System.out.print("January 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 2: System.out.print("Feburary 1, " + year + " is ");
                if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))
                    numberOfDaysInMonth = 29;
                else
                    numberOfDaysInMonth = 28;
                break;
                case 3: System.out.print("March 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 4: System.out.print("April 1, " + year + " is ");
                numberOfDaysInMonth = 30;
                break;
                case 5: System.out.print("May 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 6: System.out.print("June 1, " + year + " is ");
                numberOfDaysInMonth = 30;
                break;
                case 7: System.out.print("July 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 8: System.out.print("August 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 9: System.out.print("September 1, " + year + " is ");
                numberOfDaysInMonth = 30;
                break;
                case 10: System.out.print("October 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
                case 11: System.out.print("November 1, " + year + " is ");
                numberOfDaysInMonth = 30;
                break;
                case 12: System.out.print("December 1, " + year + " is ");
                numberOfDaysInMonth = 31;
                break;
            }
            
            switch (firstDay) {
                case 0: System.out.println("Sunday"); break;
                case 1: System.out.println("Monday"); break;
                case 2: System.out.println("Tuesday"); break;
                case 3: System.out.println("Wednesday"); break;
                case 4: System.out.println("Thursday"); break;
                case 5: System.out.println("Friday"); break;
                case 6: System.out.println("Saturday"); break;
            }
         
            // Get the start day for the next month
            firstDay = (firstDay + numberOfDaysInMonth) % 7;
        }
        
        System.exit(0);
    }
}