主方法代码：
1 public static void main(String[] args) {
2 Scanner in = new Scanner(System.in);
3 //输入年份
4 System.out.println("请输入年份(1900之后的)：");
5 int year = in.nextInt();
6 //输入月份
7 System.out.println("请输入月份：");
8 int month = in.nextInt();
9 //判断数据输入是否有误
10 if (year < 1900 || month >12 || month < 1){
11 System.out.println("对不起，你输入的数据有误！");
12 return;
13 }
14 //获取1900年到输入年份的总天数
15 int allDayOfYear = getAllDayOfYear(1900,year);
16
17 //获取输入年份从1月到输入月份的总天数
18 int allDayOfMonth = getAllDayOfMonth(year,1,month);
19
20 //获得总天数
21 int allDay = allDayOfYear + allDayOfMonth;
22 //打印日期
23 printCalendar(allDay,getDayOfMonth(year,month));
24
25 }
计算1900到输入年份的总天数的方法代码
public static int getAllDayOfYear(int startYear,int endYear){
//定义年的总天数
int allDayOfYear = 0;
for (int i = startYear; i < endYear; i++) {
if (judgeLeapYear(i)){
allDayOfYear += 366;
}else {
allDayOfYear +=365;
}
}
return allDayOfYear;
}
计算输入年份从1月到输入月份的总天数方法代码
1 public static int getAllDayOfMonth(int year,int startMonth,int endMonth){
2 int allDayOfMonth = 0;
3 for (int i = startMonth; i < endMonth; i++) {
4 allDayOfMonth += getDayOfMonth(year,i);
5 }
6 return allDayOfMonth;
7 }
获得每一个月的天数方法代码
1 public static int getDayOfMonth(int year,int month){
2 //定义月的天数
3 int day = 0;
4 switch (month){
5 case 1:
6 case 3:
7 case 5:
8 case 7:
9 case 8:
10 case 10:
11 case 12:
12 day = 31;
13 break;
14 case 4:
15 case 6:
16 case 9:
17 case 11:
18 day = 30;
19 break;
20 case 2:
21 if (judgeLeapYear(year)){
22 day = 29;
23 }else {
24 day = 28;
25 }
26 break;
27 }
28 return day;
29 }
判断是否为闰年方法代码
1 public static boolean judgeLeapYear(int year){
2 if (year % 4 == 0 && year % 100 !=0 || year % 400 == 0){
3 return true;
4 }
5 return false;
6 }
打印日历方法代码
1 public static void printCalendar(int allDay,int day){
2 //打印开头的信息
3 System.out.println("星期日\t星期一\t星期二\t星期三\t星期四\t星期五\t星期六");
4 //换行变量
5 int num = 0;
6 //计算输入的月份1号是星期几
7 int week = allDay % 7 +1;
8 for (int i = 0; i < week; i++) {
9 System.out.print("\t\t");
10 num++;
11 }
12 //打印日期
13 for (int i = 1; i <= day; i++) {
14 //判断
15 if (num %7 == 0){
16 System.out.println();
17 }
18 System.out.print(i+"\t\t");
19 num++;
20 }
21 }
