JavaSE实现万年历，javase万年历

JavaSE实现万年历，javase万年历

万年历.java

import java.util.Scanner;

public class WanNianLi {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        System.out.println("请输入年：");
        int year = s.nextInt();
        System.out.println("请输入月：");
        int month = s.nextInt();
        int days = 0;
        for (int i = 1900; i < year; i++) {
            if (a(i)) {
                days += 366;
            } else {
                days += 365;
            }
        }
        int days1 = getDays(year, month);
        days = days + days1;
        int weekday = days % 7 + 1;
        System.out.println("一\t二\t三\t四\t五\t六\t七\t");
        int firstDay = weekday;
        for (int i = 1; i < firstDay; i++) {
            System.out.print("\t");
        }
        int currentDays = getDaysInMonth(month, year);
        for (int i = 1; i <= currentDays; i++) {
            System.out.print(i + "\t");
            firstDay++;
            if (firstDay == 8) {
                firstDay = 1;
                System.out.println();
            }
        }
    }

    /**
     * 计算用户输入月份的天数
     * 
     * @param year用户输入的年
     * @param month用户输入的月
     * @return返回当月的天数
     */
    public static int getDaysInMonth(int month, int year) {
        switch (month) {
        case 1:
        case 3:
        case 5:
        case 7:
        case 8:
        case 10:
        case 12:
            return 31;
        case 4:
        case 6:
        case 9:
        case 11:
            return 30;
        case 2:
            if (a(year)) {
                return 29;
            } else {
                return 28;
            }
        }
        return 0;
    }

    /**
     * 该方法功能是，用户输入年份，判断是否为闰年
     * 
     * @param year用户输入的年份
     * @return true是闰年 false是平年
     */
    public static boolean a(int year) {
        return (((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)) ? true : false;
    }

    /**
     * 该方法计算从用户输入月份到该年的1月1日有多少天
     * 
     * @param year用户输入的年份，用来判断是否是闰年
     * @param month用户输入的月份
     * @return 返回一共有多少天
     */
    public static int getDays(int year, int month) {
        int[] y= new int[]{0,31,28,31,30,31,30,31,31,30,31,30};
        int tatol=0;
        for (int i = 0; i < month; i++) {
            tatol += y[i];
        }
        return tatol;
    }
}