public class Singleton {
    
    private Singleton ();
    
    private static Singleton Instance =new Singleton ();

    public static   Singleton getInstance (){
    
        return Instance ;
    }
           
}

public class Test{
    public static void main(String[] args){
    Singleton s1 = Singleton.getInstance();
    Singleton s2 = Singleton.getInstance();
    if(s1==s2){
        Systom.out.println("s1和s2是同一實例")
       }else{
        Systom.out.println("s1和s2不是同一實例")
        }
    }


}

　　以上是餓漢模式

模式的秘密：單例模式