package cn.dj.demo.test;
/**
* 确保此类只有一个实例
*/
public class Singleton {
public static volatile Singleton singleton;
public Singleton() {
}
public static Singleton getInstance(){
if (singleton == null){
synchronized (Singleton.class){
if (singleton == null){
singleton = new Singleton();
}
}
}
return singleton;
}
}