1、

package java.util;

public class Node2Test
{
    public static void main(String[] args)
    {
        Node2 node1 = new Node2("node1");
        Node2 node2 = new Node2("node2");
        Node2 node3 = new Node2("node3");
        
        node1.next = node2;
        node2.previous = node1;
        
        node2.next = node3;
        node3.previous = node2;
        
        node3.next = node1;
        node1.previous = node3;
        
        System.out.println("-------------");
        
        Node2 node4 = new Node2("node4");
        
        node1.next = node4;
        node4.previous = node1;
        node4.next = node2;
        node2.previous = node4;
        
        System.out.println("-------------");
        
        node1.next = node2;
        node2.previous = node1;
        node4.next = null;
        node4.previous = null;
        
    }
}

2、關于ArrayList與LinkedList 比較分析
a) ArrayList底層采用數組實現，LinkedList底層采用雙向鏈表實現
b)當執行插入或刪除操作時，采用LinkedList比較好
c)當執行搜索操作時，采用ArrayList比較好