🚀 go-pugleaf

Although it��s unnecessary, you can be more explicit using a cast, which has
the effect of calling toString( ):
��λ����������printhamster����ض�����˵�Ķ���ǰ���Ǹ�printer.
������λ����������һ��:
In general, however, you��ll want to do something more than call Object 
methods, so you��ll run up against the type-casting issue again. You must
assume you��ve gotten an Iterator to a sequence of the particular type you're 
interested in, and cast the resulting objects to that type (getting a 
run-time exception if you��re wrong). 

�� �� gjyalpha.bbs@freecity.cnzju.net (Java Enthusiast) �Ĵ������ᵽ: ��
: ��  ��: [tij]����һ������
: ����վ: Ʈ��ˮ�Ƽ� (Wed Feb  4 12:42:33 2004)
: ת��վ: NanKai!news.happynet.org!news.ccie.net.cn!Freecity
: 
: ��think in java 2 Ӣ�İ��457-458ҳ�����İ�329ҳ
: 
: ������һ������
: //: c09:HamsterMaze.java
: // From 'Thinking in Java, 2nd ed.' by Bruce Eckel
: // www.BruceEckel.com. See copyright notice in CopyRight.txt.
: // Using an Iterator.
: import java.util.*;
: 
: class Hamster {
:   private int hamsterNumber;
:   Hamster(int i) { hamsterNumber = i; }
:   public String toString() {
:     return "This is Hamster #" + hamsterNumber;
:   }
: }
: 
: class Printer {
:   static void printAll(Iterator e) {
:     while(e.hasNext())
:       System.out.println(e.next());
:   }
: }
: 
: public class HamsterMaze {
:   public static void main(String[] args) {
:     ArrayList v = new ArrayList();
:     for(int i = 0; i < 3; i++)
:       v.add(new Hamster(i));
:     Printer.printAll(v.iterator());
:   }
: } ///:~
: 
: Bruce˵��
: ��Ȼû�б�Ҫ������Ҳ�����ֶ����ת�ͣ�Ч��͵���toString()��ͬ
:      System.out.println((String)e.next());
: 
: ���Ǵ������Ǿ�ij�������䡣����ı�����û������ģ�����ִ���ڻ��д�ġ�
: ClassCastException��
: 
: 
: 
: 
: --
: gjyalpha ��˭��������gjyalpha ��
: 
: �� ��Դ:��Ʈ��ˮ�Ƽ� freecity.cnzju.net��[FROM: gjyalpha]
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