﻿<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/"><channel><title>BlogJava-Cboy-随笔分类-JAVA学习笔</title><link>http://www.blogjava.net/Cboy/category/6501.html</link><description /><language>zh-cn</language><lastBuildDate>Sat, 03 Mar 2007 04:32:18 GMT</lastBuildDate><pubDate>Sat, 03 Mar 2007 04:32:18 GMT</pubDate><ttl>60</ttl><item><title>集合</title><link>http://www.blogjava.net/Cboy/archive/2005/12/30/25974.html</link><dc:creator>大森林</dc:creator><author>大森林</author><pubDate>Thu, 29 Dec 2005 19:33:00 GMT</pubDate><guid>http://www.blogjava.net/Cboy/archive/2005/12/30/25974.html</guid><wfw:comment>http://www.blogjava.net/Cboy/comments/25974.html</wfw:comment><comments>http://www.blogjava.net/Cboy/archive/2005/12/30/25974.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.blogjava.net/Cboy/comments/commentRss/25974.html</wfw:commentRss><trackback:ping>http://www.blogjava.net/Cboy/services/trackbacks/25974.html</trackback:ping><description><![CDATA[集合：<br>
Vector 和Enumeration 一对<br><br>
如<br><br><br>

Vector v = new Vector();<br>
Enumeration e = v.elements();<br>
e.nextElement  指示器正指向的元素对象<br>
e.hasMoreElements 回是否还有元素<br><br><br><br>


List 和Iterator 一对<br>
如<br><br><br>

ArrayList al = new ArrayList();<br>
Iterator it = al.iterator();<br>
it.next();<br>
it.hasNext();
<br><br><br>
附加一句：排序使用Collections 的一个静态方法:Collections.sort(集合对象);<br>
<img src ="http://www.blogjava.net/Cboy/aggbug/25974.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.blogjava.net/Cboy/" target="_blank">大森林</a> 2005-12-30 03:33 <a href="http://www.blogjava.net/Cboy/archive/2005/12/30/25974.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>instanceof比较</title><link>http://www.blogjava.net/Cboy/archive/2005/12/30/25973.html</link><dc:creator>大森林</dc:creator><author>大森林</author><pubDate>Thu, 29 Dec 2005 19:20:00 GMT</pubDate><guid>http://www.blogjava.net/Cboy/archive/2005/12/30/25973.html</guid><wfw:comment>http://www.blogjava.net/Cboy/comments/25973.html</wfw:comment><comments>http://www.blogjava.net/Cboy/archive/2005/12/30/25973.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.blogjava.net/Cboy/comments/commentRss/25973.html</wfw:commentRss><trackback:ping>http://www.blogjava.net/Cboy/services/trackbacks/25973.html</trackback:ping><description><![CDATA[instanceof 比较时会连父类一起比较<br>
如<br>

class A{}<br><br><br>



class B extendsA{}<br><br><br>




public class Test<br>

{<br>

    public static void main(String args[])<br>

    {<br>

     B b= new B();<br>

     biJiao(b);<br>

     }<br>

}<br><br><br>



有一方法<br><br><br>



biJiao(object obj)<br>

{<br>

   if (ojb instanceof  A   )<br>

    {<br>

         System.out.println("这里会显示True");  <br>

    }<br>

}<br><br>
<br>



这样不能显示唯一的,要显示唯一的用 Class 方法.每个类都会有一个唯一的Class.如这里改成<br>
<br>
<br>

biJiao(object obj)<br>

{<br>

   if (ojb.getClass==A.Class()   )<br>

    {<br>

         System.out.println("这里会显示False");  <br>

    }<br>

}<br>
<img src ="http://www.blogjava.net/Cboy/aggbug/25973.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.blogjava.net/Cboy/" target="_blank">大森林</a> 2005-12-30 03:20 <a href="http://www.blogjava.net/Cboy/archive/2005/12/30/25973.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item></channel></rss>