Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

·¢ÏÖÒ»¸öc++¶à̬Óëjava¶à̬²»Í¬µÄµØ·½

¸Õ¸Õ¿´µ½Ò»ÆªÎÄÕÂÌá³öc++¶à̬Óëjava¶à̬²»Í¬µÄµØ·½£¬»ù±¾Òâ˼ÈçÏ£º
Çë¿´C++´úÂ룺
class Base
{
public:
 Base()
 {
  init(); 
 }
 virtual ~Base() {}
protected:
 int value;
 virtual void init() 
 { 
  value = 100;     
 }
};
class Derived : public Base
{
public:
 Derived()
 {
  init();
 }
protected:
 void init() 
 {
  cout << "value = " << value << endl;
  // ×öһЩ¶îÍâµÄ³õʼ»¯¹¤×÷ 
 }
};
int main(int argc, char* argv[])
{
 Base* pb;
 pb = new Derived();
 delete pb;
 return 0;
}
Ö´Ðнá¹ûÊÇ
value = 100
ÔÙ¿´java´úÂ룺
class Base
{
  public Base()
  {
    init();
  }
  protected int value;
  protected void init()
  {
         value = 100;  
  }
}
class Derived extends Base
{
  public Derived()
  {
    init();
  }
  protected void init()
  {
    System.out.println("value = " + value);
    // ×öһЩ¶îÍâµÄ³õʼ»¯¹¤×÷
  }
}
public class Test
{
  public static void main(String[] args)
  {
    Base base = new Derived();
  }
}
Ö´Ðнá¹ûÊÇ
value = 0
value = 0
ÔÚjavaÖÐ×ÓÀàµÄinit·½·¨ÖØÐ´Á˸¸ÀàµÄinit·½·¨£¬µ¼Ö²»ÄÜÕýÈ·Íê³É³õʼ»¯¡£¿´µ½ÕâÀïÎÒ˼¿¼ÁËһϣ¬ÓÉÓÚ×ÓÀàÖØÐ´Á˸¸ÀàµÄͬÃûº¯Êý£¬²Åµ¼Ö±¾Ó¦¸ÃÖ´Ðеĺ¯ÊýûÓÐÖ´ÐУ¬Èç¹ûÐ޸ĸ¸ÀàµÄ³õʼ»¯º¯Êý»òÕß×ÓÀàµÄ³õʼ»¯º¯Êý£¬Ê¹×ÓÀ಻»á·¢ÉúÖØÐ´£¬ÊDz»ÊǾͲ»»á·¢ÉúÉÏÃæµÄÇé¿ö£¿»òÐí¼´Ê¹ÊÇ×ÓÀàÓ븸À࣬µ±Éæ¼°µ½¸÷×Եijõʼ»¯µÄµØ·½Ê±¾Í²»Ó¦¸ÃʹÓöà̬ÐÔ¡£


Ïà¹ØÎĵµ£º

Thinking in Java Ö®String ÕýÔò±í´ïʽ

       Ê²Ã´ÊÇÕýÔò±í´ïʽ£¿
       ÕýÔò±í´ïʽÊÇÒ»ÖÖÇ¿´ó¶øÁé»îµÄÎı¾´¦Àí¹¤¾ß¡£Ê¹ÓÃÕýÔò±í´ïʽ£¬ÎÒÃÇÄܹ»ÒÔ±à³ÌµÄ·½Ê½£¬¹¹Ô츴ÔÓµÄÎı¾Ä£Ê½£¬²¢¶ÔÊäÈëµÄ×Ö·û´®½øÐÐËÑË÷¡£Ò»µ©ÕÒµ½ÁËÆ¥ÅäÕâЩģʽµÄ²¿·Ö£¬Äã¾ÍÄܹ»ËæÐÄËùÓûµØ¶ÔËüÃǽøÐд¦Àí¡£ÕýÔò±í´ïÊ½Ì ......

domino java ´úÀíµ÷ÓÃÊÜÏÞÖÆÀà






  ÔÚDOMINOÖÐʹÓÃHibernateʱ£¬»á³öÏÖÒÔϵĴíÎó£º
ÎÊÌâÊÇÓÉÓÚdomino jre µÄĬÈϰ²È«²»Ö§³ÖReflectPermission "suppressAccessChecks";
ÔÚDOMINO JVMµÄ°²È«²ßÂÔÎļþÖмÓÈë
permission java.lang.reflect.ReflectPermission
" ......

javaµÄvolatileÊÇʲôÒâ˼


ÎÒÃÇÖªµÀ£¬ÔÚJavaÖÐÉèÖñäÁ¿ÖµµÄ²Ù×÷£¬³ýÁËlongºÍdoubleÀàÐ͵ıäÁ¿Íâ¶¼ÊÇÔ­×Ó²Ù×÷£¬Ò²¾ÍÊÇ˵£¬¶ÔÓÚ±äÁ¿ÖµµÄ¼òµ¥¶Áд²Ù×÷ûÓбØÒª½øÐÐͬ²½¡£
ÕâÔÚJVM 1.2֮ǰ£¬JavaµÄÄÚ´æÄ£ÐÍʵÏÖ×ÜÊÇ´ÓÖ÷´æ¶ÁÈ¡±äÁ¿£¬ÊDz»ÐèÒª½øÐÐÌØ±ðµÄ×¢ÒâµÄ¡£¶øËæ×ÅJVMµÄ³ÉÊìºÍÓÅ»¯£¬ÏÖÔÚÔÚ¶àÏ̻߳·¾³ÏÂvolatile¹Ø¼ü×ÖµÄʹÓñäµÃ·Ç³£ÖØÒª¡£
ÔÚµ±Ç° ......

JavaÈÕÆÚ¸ñʽ»¯³£Ó÷½·¨

JavaÖÐDateÀàÖеÄһЩÈÕÆÚ¸ñʽ»°·½·¨¶¼ÒѹýÆÚ£¬ËùÒÔ²»ÍƼöʹÓá£
Ò»°ã¸ñʽ»¯Ê±£¬³£Óõ½ÕâÁ½¸öÀࣺCalendar
ºÍSimpleDateFormat
£¬Ê¹Ó÷½·¨ÈçÏ£º
1.CalendarÀà
CalendarÀàÊÇabstractµÄ£¬ËùÒÔʵÀý»¯·½Ê½µÃÓþ²Ì¬·½·¨£º
Calendar c = Calendar.getInstance();£¬
´ËʱµÄÉú³ÉµÄʵÀýÒÀ¾ÝµÄÊǵ±Ç°ÏµÍ³Ê±¼ä£»c.setTime(java ......

java¼Ì³ÐÎÊÌâ ¾­³£Óöµ½±£´æÏÂÀ´

import java.util.ArrayList;
import java.util.HashMap;

public class Client {

/**
* @param args
*/
public static void main(String[] args) {
test1();
System.out.println("==================================");
test2(); ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ