Java单态模式例程

class Single {
    private static Single s = new Single();
    
    //单态模式设计,这里的构造函数是私有的,所以不能new
    private  Single(){}
    //只能通过调用getInstance()得到Single的引用
    public static Single getInstance(){
        return s;
    }

    public void print(){
        System.out.println("Hello Java");
    }
}

public class Test {
    public static void main(String args[]){
        Single s1 = null;
        s1 = Single.getInstance();
        s1.print();
        Single s2 = Single.getInstance();
        System.out.println(s2);
        System.out.println(s1);
    }
}