/**
* 饿汉模式
*/
public class Instance {
private static Instanceinstance=new Instance ();
private Instance(){}
public static InstancegetInstance(){
return instance;
}
}
/**
* 懒汉模式（线程不安全）
*/
class Singleton{
private static Singletoninstance;
private Singleton(){}
public static SingletongetInstance(){
if(instance==null){
instance=new Singleton ();
}
return instance;
}
}
/**
* 懒汉模式（线程安全）
*/
class SingletonOne{
private static SingletonOneinstance;
private SingletonOne(){}
public static synchronized SingletonOnegetInstance(){
if(instance==null){
instance=new SingletonOne ();
}
return instance;
}
}
