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Integer var = new Integer();//ÓÐÓï·¨´íÎó
Integer var = new Integer(2);//悦﵀
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Vector::public Enumeration<E> elements() ·µ»Ø´ËÏòÁ¿µÄ×é¼þµÄö¾Ù¡£
Vector v = new Vector();
v.add("aaaaaaaa");
v.add("bbbbbbbbbbbb");
for (Enumeration e = v.elements(); e.hasMoreElements();)
{
System.out.println(e.nextElement());
}
//Êä³ö
//aaaaaaaa
//bbbbbbbbbbbb
½Ó¿ÚµÄʵÏÖ£ºFilenameFilterÊǽӿÚ
String[] names=f.list(new FilenameFilter()//µÃµ½ÒÔÉÏÎļþ¼ÐÏÂËùÓеÄÎļþÃûºÍĿ¼Ãû,´æ´¢ÔÚnamesÊý×éÖÐ
{
public boolean accept(File dir,String name)
{
return name.indexOf(".java")!=-1;
}
});
getClass().getName();
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1. import java.util.*;
2.(A) public class Test
{ public static void main(String[] args)
{
//Éú³É [0-n) ¸ö²»Öظ´µÄËæ»úÊý st ÓÃÀ´±£´æ ......
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1. ÄãÐèÒª¾«Í¨ÃæÏò¶ÔÏó·ÖÎöÓëÉè¼Æ£¨OOAOOD£©¡¢É漰ģʽ£¨GOF£¬J2EEDP£©ÒÔ¼°×ÛºÏģʽ¡£ÄãÓ¦¸ÃÁ˽âUML£¬ÓÈÆäÊÇclass¡¢object¡¢interactionÒÔ¼°statediagrams. ¡¡¡¡2. ÄãÐèҪѧϰJavaÓïÑԵĻù´¡ÖªÊ¶ÒÔ¼°ËüµÄºËÐÄÀà¿â£¨collections¡¢serialization¡¢streams¡¢networking¡¢multithreading¡¢reflection¡¢event¡¢handling¡¢N ......
import lotus.domino.*;
import java.io.*;
import java.util.Vector;
import jxl.*;
/*******************************************************************************
* @saveSQMessageToOracle
* @×÷ÕߣºÐ컪Ïé
* @2009Äê10ÔÂ28ÈÕ
* @˵Ã÷£ºExeclÎļþµÄµ¼Èë
********** ......
import java.io.*;
class FileTest
{
public static void main(String[] args) throws Exception
{
//File f=new File("1.txt");
//f.createNewFile();
//f.mkdir();
//File f=new File("E:\\JavaLesson\\Lesson7\\1.txt");//ÔÚWindowsϵͳÏÂ,Óþø¶Ô ......