Algs4-1.3.16从文件中读取日期生成日期对象数组

最新推荐文章于 2019-03-30 17:27:31 发布

weixin_33736832

最新推荐文章于 2019-03-30 17:27:31 发布

阅读量136

点赞数

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/longjin2018/p/9849468.html

本文详细介绍了一种用于解析和格式化日期的智能算法。该算法通过读取标准输入中的日期字符串，将其转换为SmartDate对象数组，同时验证日期的有效性，包括闰年和平年的规则。此外，还提供了一个方法来确定一周中的哪一天。

1.3.16使用1.3.1.5节中的readInts()作为模板为Date编写一个静态方法readDates(),从标准输入中读取由练习1.2.19的表格所指定的格式的多个日期并返回一个它们的数组。
答：public static SmartDate[] readDates(String name)

public class SmartDate
{
   private final int myYear;
   private final int myMonth;
   private final int myDay;

   public SmartDate(String date)
   {
       String[] words=date.split("/");
       int month=Integer.parseInt(words[0]);
       int day=Integer.parseInt(words[1]);
       int year=Integer.parseInt(words[2]);
       //
      mySmartDate(month,day,year);
      //
       myYear=year;
       myMonth=month;
       myDay=day;
   }

    public SmartDate(int month,int day,int year)
    {
        mySmartDate(month,day,year);
        //
        myYear=year;
        myMonth=month;
        myDay=day;
        //
      }

    private void mySmartDate(int month,int day,int year)
    {
        if(year<0)       throw new IllegalArgumentException("year is error.");
        if(month<1 || month>12)    throw new IllegalArgumentException("month is error.");
        if(day<1 || day>31)    throw new IllegalArgumentException("day is error.");
        if(month%2==0 && day>30) throw new IllegalArgumentException("day is error.");
        if(year%400!=0 && (!(year%4==0 && year%100!=0)) && month==2 && day>28) throw new IllegalArgumentException("day is error.");
        if((year%400==0 || (year%4==0 && year%100!=0)) && month==2 && day>29) throw new IllegalArgumentException("day is error.");
    }

    public int month()
    {
        return myMonth;
    }

    public int day()
    {
        return myDay;
    }

    public int year()
    {
        return myYear;
    }

    public String dayOfTheWeek()
    {
        int w=(myYear%100+(myYear%100)/4+(myYear-myYear%100)/4-2*(myYear-myYear%100)+26*(myMonth+1)/10+myDay-1)%7;
        if(w<0) w=w+7;
        String weekstr="";
        switch(w)
        {
            case 0: weekstr="Sunday"; break;
            case 1: weekstr="Monday"; break;
            case 2: weekstr="Tuesday"; break;
            case 3: weekstr="Wednesday"; break;
            case 4: weekstr="Thursday"; break;
            case 5: weekstr="Friday"; break;
            case 6: weekstr="Saturday"; break;
        }
      return weekstr;
    }

    public String toString()
    {
        return month()+"/"+day()+"/"+year();
    }

    public static SmartDate[] readDates(String name)
    {
        In in=new In(name);
        Queue<String> q=new Queue<String>();
        while(!in.isEmpty())
            q.enqueue(in.readString());
        int N=q.size();
        SmartDate[] a=new SmartDate[N];
        for(int i=0;i<N;i++)
            a[i]=new SmartDate (q.dequeue());
        return a;
    }

    public static void main(String[] args)
    {
        SmartDate[] b=SmartDate.readDates(args[0]);
        for(int i=0;i<b.length;i++)
            StdOut.printf("%s\n",b[i].toString());
    }
}

转载于:https://www.cnblogs.com/longjin2018/p/9849468.html