求任意年份任意月份的天数

import java.util.Scanner;/** * 求任意一年任意一月的天数 * @author KiMin *  2012-11-29 */public class Test {  public static void main(String[] args) {    Scanner scan = new Scanner(System.in);    System.out.print("请出入年份：");  int year = scan.nextInt();  System.out.println("请出入月份：");  int month = scan.nextInt();    int datOfMonth = 0;    switch (month) {  case 1:  case 3:  case 5:  case 7:  case 8:  case 10:  case 12:   datOfMonth = 31;   break;  case 2:   if (isRunNian(year)) {    datOfMonth = 29;   } else {    datOfMonth = 28;   }   break;  default:   datOfMonth = 30;   break;  }    System.out.println(year + "年的" + month + "月共有" + datOfMonth + "天"); }  // 判断是否是闰年 public static boolean isRunNian (int year) {  boolean flag = false;    if (year/4 == 0     || (year/100 == 0 && year/400 != 0)) {   flag = true;  }    return flag; }}