假日结束，散分，顺便给个基础面试题

package com.zf.link;public class Test2 {    //打印结果 为的多少 ， 心算    public static void main(String[] args) {                Node n1 = new Node(1);        Node n2 = new Node(2);        Node n3 = new Node(3);                n1.setNext(n2);        n2.setNext(n3);                n2 = n2.next();                System.out.println(n2.data);            System.out.println(n1.next().data);                    }    }class Node{        public int data ;        private Node next ;        public Node(int data){        this.data = data ;    }        public void setNext(Node node){        next = node;    }        public Node next(){         return next;    }    }