java从键盘输入年份和月份， 输出该月份的日历表：

以下是一个基于控制台的 Java 代码示例，用于输入年份和月份，然后输出该月份的日历表：

import java.util.Scanner;

public class PrintCalendar {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        
        // 输入年份和月份
        System.out.print("请输入年份: ");
        int year = input.nextInt();
        System.out.print("请输入月份: ");
        int month = input.nextInt();
        
        // 计算当月第一天是星期几
        int firstDayOfWeek = getFirstDayOfWeek(year, month);
        
        // 输出日历表头
        System.out.printf("%10s%s\n", "", getMonthName(month) + " " + year);
        System.out.println("-------------------------------------------------");
        System.out.printf("%s%s%s%s%s%s%s\n", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat");
        
        // 输出日历表格
        for (int i = 0; i < firstDayOfWeek; i++) {
            System.out.printf("%4s", "");
        }
        for (int i = 1; i <= getNumDaysInMonth(year, month); i++) {
            System.out.printf("%4d", i);
            if ((i + firstDayOfWeek) % 7 == 0) {
                System.out.println();
            }
        }
    }
    
    // 获取指定年份、月份的第一天是星期几（0 表示星期日，1 表示星期一，依次类推）
    public static int getFirstDayOfWeek(int year, int month) {
        int day = 1;
        if (month < 3) {
            month += 12;
            year--;
        }
        int century = year / 100;
        year %= 100;
        int weekday = (day + 13 * (month + 1) / 5 + year + year / 4 + century / 4 + 5 * century) % 7;
        return (weekday + 6) % 7;
    }
    
    // 获取指定月份的天数
    public static int getNumDaysInMonth(int year, int month) {
        int numDays = 0;
        switch (month) {
            case 1: numDays = 31; break;
            case 2:
                if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0)) {
                    numDays = 29;
                } else {
                    numDays = 28;
                }
                break;
            case 3: numDays = 31; break;
            case 4: numDays = 30; break;
            case 5: numDays = 31; break;
            case 6: numDays = 30; break;
            case 7: numDays = 31; break;
            case 8: numDays = 31; break;
            case 9: numDays = 30; break;
            case 10: numDays = 31; break;
            case 11: numDays = 30; break;
            case 12: numDays = 31; break;
            default: break;
        }
        return numDays;
    }
    
    // 获取指定月份的名称
    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"; break;
            default: break;
        }
        return monthName;
    }
}

运行代码后，会提示输入年份和月份，然后输出该月份的日历表。例如，输入 2022 和 9，会输出如下的日历表：

          September 2022
-------------------------------------------------
SunMonTueWedThuFriSat
              1  2  3
 4  5  6  7  8  9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30