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package pattern.singleton.basic;
/**
* javaÉè¼ÆÄ£Ê½£ºµ¥Àýģʽ£¨¶öººÊ½£©
* @author wasw100
*/
public class Singleton {
// Ìṩһ¸ö¾²Ì¬Ë½ÓбäÁ¿Ö¸Ïò×Ô¼º,ÊôÓÚÀà
private static Singleton instance = new Singleton();// ÌáǰÏû·Ñ
// Ìṩ˽Óй¹ÔìÆ÷£¬Ö»ÓÐÔÚµ±Ç°ÀàÖпÉÒÔʹÓÃnew,Íâ½ç²»Äܹ¹Ôì¸ÃÀàµÄ¶ÔÏó
private Singleton() {
}
// ¶ÔÍâÌṩһ¸ö¹«¹²·ÃÎʵã
public static Singleton getInstance() {
return instance;
}
}
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package pattern.singleton.basic;
/**
* javaÉè¼ÆÄ£Ê½£ºµ¥Àýģʽ£¨ÀÁººÊ½£©
* @author wasw100
*/
public class Singleton {
private static Singleton instance = null;
private Singleton(){}
//synchronized±ÜÃâÔÚ·ÃÎÊÁ¿±È½Ï´óµÄʱºò µÚÒ»¸öÏ̵߳Änew Singleton»¹Ã»À´µÃ¼°¸³Öµ¸øinstance£¬µÚ¶þ¸öÏ߳̾ÍÀ´ÁË£¬»¹Òª½øÐÐnew ……
public synchronized static Singleton getInstance(){
if(instance == null){
instance = new Singleton();
}
return instance;
}
}
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package pattern.singleton.basic;
public class ClientClass {
public static void main(String [] args){
Singleton s1 = Singleton.getInstance();
Singleton s2 = Singleton.getInstance();
System.out.println(s1);
System.out.println(s2);
}
}
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pattern.singleton.basic.Singleton@a90653
pattern.singleton.basic.Singleton@a90653
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ÀÁººÊ½ÖÐsynchronized±ÜÃâÔÚ·ÃÎÊÁ¿±È½Ï´óµÄʱºò µÚÒ»¸öÏ̵߳Änew Singleton»¹Ã»À´µÃ¼°¸³Öµ¸øinstance£¬µÚ¶þ¸öÏ߳̾ÍÀ´ÁË£¬»¹Òª½øÐÐnew ……
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