week2.java

书本JAVA2程序教程中的程序例子。 对于初学者是很好的帮助。 浅显易懂。

public class Week2
{
    public static void main(String args[]) 
    {
        int year=2002,month=7,day=8,total,week;
        boolean leap=false;
        leap = (year%400==0)| (year%100!=0) & (year%4==0);
        week =1;                            //起始日 1979-12-31 is Monday 
        total = year-1980+(year-1980+3)/4;       //求平(闰)年累计的总天数
        for (int i=1;i<month;i++)                 //当年的累计天数
            switch  (i)
            {
                case 1:
                case 3:
                case 5:
                case 7:
                case 8:
                case 10:
                case 12: total=total+31; 
                         break;
                case 4: 
                case 6: 
                case 9: 
                case 11: total=total+30; 
                         break;
                case 2:  if (leap)
                             total=total+29;
                         else 
                             total=total+28;
                         break;
             }
        total = total+day;                       //当月的天数
        week = (week+total) % 7;                 //求得星期几
        System.out.print("date "+year+'-'+month+'-'+day+" is ");
        switch (week)
        {
            case 0: System.out.println("Sunday");   break;
            case 1: System.out.println("Monday");   break;
            case 2: System.out.println("Tuesday");  break;
            case 3: System.out.println("Wednesday");break;
            case 4: System.out.println("Thursday"); break;
            case 5: System.out.println("Friday");   break;
            case 6: System.out.println("Saturday"); break;
        }
    }
}