java万年历

好的，我可以帮你写一个 Java 万年历程序。以下是代码示例：

import java.util.Scanner;

public class Calendar {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入年份：");
        int year = input.nextInt();
        System.out.print("请输入月份：");
        int month = input.nextInt();

        // 计算这个月的天数
        int days = getDaysOfMonth(year, month);

        // 计算这个月的第一天是星期几
        int firstDayOfWeek = getFirstDayOfWeek(year, month);

        // 打印日历表头
        System.out.println("日\t一\t二\t三\t四\t五\t六");

        // 打印日历内容
        int day = 1;
        for (int i = 0; i < 6; i++) {
            for (int j = 0; j < 7; j++) {
                if (i == 0 && j < firstDayOfWeek) {
                    System.out.print("\t");
                } else if (day > days) {
                    break;
                } else {
                    System.out.print(day + "\t");
                    day++;
                }
            }
            System.out.println();
        }
    }

    // 获取指定年月的天数
    public static int getDaysOfMonth(int year, int month) {
        int days = 0;
        switch (month) {
            case 2:
                if (isLeapYear(year)) {
                    days = 29;
                } else {
                    days = 28;
                }
                break;
            case 4:
            case 6:
            case 9:
            case 11:
                days = 30;
                break;
            default:
                days = 31;
                break;
        }
        return days;
    }

    // 判断指定年份是否是闰年
    public static boolean isLeapYear(int year) {
        return (year % 4 == 0 && year % 100 != 0) || year % 400 == 0;
    }

    // 获取指定年月的第一天是星期几
    public static int getFirstDayOfWeek(int year, int month) {
        int century = year / 100;
        year = year % 100;
        int dayOfWeek = (1 + 5 * (year % 4) + 4 * (year % 100) + 6 * (year % 400)) % 7;
        if (century == 18) {
            dayOfWeek += 2;
        } else if (century == 20) {
            dayOfWeek += 6;
        }
        switch (month) {
            case 1:
                break;
            case 2:
                dayOfWeek += 3;
                break;
            case 3:
                dayOfWeek += 3;
                break;
            case 4:
                dayOfWeek += 6;
                break;
            case 5:
                dayOfWeek += 1;
                break;
            case 6:
                dayOfWeek += 4;
                break;
            case 7:
                dayOfWeek += 6;
                break;
            case 8:
                dayOfWeek += 2;
                break;
            case 9:
                dayOfWeek += 5;
                break;
            case 10:
                dayOfWeek += 0;
                break;
            case 11:
                dayOfWeek += 3;
                break;
            case 12:
                dayOfWeek += 5;
                break;
        }
        return dayOfWeek % 7;
    }
}

你可以直接运行这个程序，输入年份和月份，即可输出对应的万年历。