如图打印如下日历图片
有兴趣的话，建议读者构建一个思维导图，以方便生成解决方案
/*
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* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package printcalendar;
import java.util.Scanner;
/**
*
* @author Hacker.ST.Tan
*/
public class PrintCalendar {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
Scanner input = new Scanner(System.in);
System.out.print("Enter full year (e.g., 2017):");
int year = input.nextInt();
System.out.print("Enter month as a number between 1 and 12:");
int month = input.nextInt();
print12(year, month);
}
//打印至month開始之後的所有月份的日曆
public static void print12(int year, int month) {
for (int month1 = month; month1 <= 12; ++month1) {
printMonth(year, month1);
}
}
//答應日曆函數
public static void printMonth(int year, int month) {
printMonthTitle(year, month);
printMonthBody(year, month);
}
//打印標題
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");
}
//確定輸入的月份
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;
}
//打印日曆的主體
public static void printMonthBody(int year, int month) {
int startDay = getStartDay(year, month);
int numberOfDaysInMonth = getNumberOfDaysInMonth(year, 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();
}
public static int getStartDay(int year, int month) {
final int START_DAY_FOR_JAN_1_1800 = 3;//1800/1/1是星期三
int totalNumberOfDays = getTotalNumberOfDays(year, month);
return (totalNumberOfDays + START_DAY_FOR_JAN_1_1800) % 7;
}
//獲得1800/1/1距今日是多少天，因為已知18001/1是星期三
public static int getTotalNumberOfDays(int year, int month) {
int total = 0;
for (int i = 1800; i < year; ++i) {
if (isLeapYear(i)) {
total = total + 366;
} else {
total = total + 365;
}
}
for (int i = 1; i < month; ++i) {
total = total + getNumberOfDaysInMonth(year, i);
}
return total;
}
//獲得month的天數，即month是31天還是30天，還是29或28天
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;
}
//判斷是否為閏年
public static boolean isLeapYear(int year) {
return year % 400 == 0 || (year % 4 == 0 && year % 100 != 0);
}
}