week2.java

《Java核心技术应用开发》电子工业出版社书籍源代码

/**
 * Week2.java
 *
 */

package sample;

import java.util.*;
   
public class Week2 {
   
      private int weeknr;
      private int year;
   
      public Week2(int weeknr, int year) {
         this.weeknr = weeknr;
        this.year = year;
     }
  
     public Iterator getDays() {
         return new Iterator() {
             String text = "DayIterator for week " + weeknr + 
           " of " + year;
           int index = 0;
           Calendar cal = null;
         
           public boolean hasNext() {
              if(cal == null ){
                  cal = new GregorianCalendar();
                   cal.clear();
                   cal.set(Calendar.YEAR, getYear());
                   cal.set(Calendar.WEEK_OF_YEAR, getWeeknr());
              }
               return index < 7;
           }
  
           public Object next() {
              cal.set(Calendar.DAY_OF_WEEK, index++);
              return cal.getTime();
           }
  
           public void remove() {
              // not implemented
           }
  
           public String toString() {
              return text;
           }
        };
      
     }
  
    public int getWeeknr() {
        return weeknr;
     }
  
     public int getYear() {
        return year;
     }

     public static void main(String[] args) {
        // list the days of the week
        if (args.length < 2) {
           System.err.println("Usage: java Week <weeknr> year>");
           System.exit(1);
        } else {
           try {
              int weeknr = Integer.parseInt(args[0]);
              int year = Integer.parseInt(args[1]);
              Week wk = new Week(weeknr, year);
              for (Iterator i=wk.getDays();i.hasNext();) {
                 System.err.println(i.next());
              }
           } catch (NumberFormatException x) {
              System.err.println("Illegal week or year");
           }
        }
     }
}