谁看下我的代码，错在哪？链表加数组

//我想弄个链表加数组的数据模式，但是代码终出错
public class NodeTest
{
    private final static int size = 10 ;
    private static Node node = new Node(size ,null ,null );
    private  int low = 0 ;
    private Node nextnode = node ;
    public NodeTest()
    {
        node.next = node.previous = node;
    }
    public  Node addBeforen()
    {
            nextnode = new Node(size,node,node.previous);
            nextnode.next.previous = nextnode;
            nextnode.previous.next = nextnode;
            low = 0;
        return nextnode;
      
    }
   
    public  Boolean add(String a)
    {   
        if(low+1>size)
        addBeforen();
        nextnode.date[low++] = a ;
        return true;
    }
   
   
    public static void main(String[] agrs)
    {
        NodeTest test = new NodeTest();
            for(int i = 0 ;i < 20; i++)
            test.add("a");
            System.out.println(test);
      
   
    }
}
public class Node
{
   
    String []date ;      
    Node next;
    Node previous;
    public Node( int date , Node next, Node previos)
    {
        this.date =  new String [date];
        this.next =  next;
        this.previous = previous;
    }
   
}