万年历

package calender;
/**
 *操作打印任意一年的日历的类 
 * 
 */
public class TextControl {
    //定义静态变量， 一边其他类调用
    public static int year, mothDay, weekDay;
    /**
     * usage: 判断是否是润年
     *@param int y 年份
     *@return    
     */
    public static boolean isLeapYear(int y) {
        return ((y % 4 == 0  &&  y %100 != 0)  || (y %400 == 0));
    }

    /**
     * usage: 计算该年的第一天是星期几
     * @param int y 年份
     * @return int 星期几
     */
    public static int firstDay(int y ) {
        long n = y * 365;
        for ( int i = 1; i < y ; i ++  ) {
            if (isLeapYear(i)) {
                n += 1;
            }
        }
        return (int) n % 7;
    }    
    
    /**
     *usage: 打印标题
     * 
     */
    public static void printWeekTitle() {
        System.out.println("==========================");
        System.out.println("日\t一\t二\t三\t四\t五\t六");
    }
    
    /**
     *usage:  获取 每个月的天数
     * @param int m 月份
     */
    public static int getMonthDay(int m) {
        switch(m) { 
        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 (isLeapYear(year))
                return 29;
            else
                return 38;
        default:
            return 0;

        } 
    }
    /**
     *usage: 分别按不同条件依次打印每月
     */
    public static void printMonth() {
        for (int m = 1; m <= 12; m++) {
            //打印标题
            System.out.println(m + "月");
            printWeekTitle();
            //按每个月第一天是星期几打印相应的空格
            for (int j = 1; j <= weekDay; j++) {
                System.out.print("\t");
            }
            //获取每个月的天数
            int monthDay = getMonthDay(m) ;
            for (int d = 1; d < monthDay; d ++) {
                if (d < 10) {
                    System.out.print(d + "\t ");
                }else {
                    System.out.print(d + "\t");
                }
                weekDay = (weekDay + 1) % 7;
                if (weekDay == 0) {
                    System.out.println();
                }
            }
            System.out.println('\n');
        }
    }
    
    
    
    
}

主程序：

package calender;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Calender {
	public static void main(String[] args) {
		System.out.println("请输入一个年份 ： ");
		InputStreamReader isr = new InputStreamReader(System.in);
		BufferedReader br = new BufferedReader(isr);
	
		String s;
		try {
			s = br.readLine();
			
			TextControl.year = Integer.parseInt(s);
			
			TextControl.weekDay = TextControl.firstDay(TextControl.year);
			
			System.out.println("\n       " + TextControl.year + "年          ");
			TextControl.printMonth();
			
		
		} catch (IOException e) {
			e.printStackTrace();
		}
		
	}
}