java完美单例模式

完美单例模式

单例模式的各种概念网上有很多,这里直接贴代码:

//classholder
public class Singleton {
        private Singleton(){}
        private static class SingletonHolder(){
                private static final Singleton INSTANCE = new Singleton();
        }
        public static final Singleton getInstance(){
                return SingletonHolder.INSTANCE;
        }
}