//饿汉式:
class Single{//类一加载,对象就已经存在了。
static Single s = new Single();
private Single(){ }
public static Single getInstance(){
return s;
}
}
//懒汉式:
class single2{//类加载进来,没有对象,只有调用了getInstance方法时,才会创建对象
//延迟加载形式。
private static single2 s = null;
private single2(){}
public static single2 getInstance(){
if(s==null){
synchronized(single.class){
if(s==null)
s = new single2();
}
}
return s;
}
}
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