使用基本的連結串列結構實現棧，佇列和包三種資料結構。首先用一個巢狀類來定義結點的抽象資料型別：

private class Node{
    Item item;
    Node next;
}

（1）堆疊Stack

import java.util.Iterator;
public class Stack<Item> implements Iterable<Item>{
    private Node first;//棧頂
    private int N;//元素數量
    private class Node{
        Item item;
        Node next;
    }
    public
 
 void push(Item item){
        Node oldfirst = first;
        first = new Node();
        first.item = item;
        first.next = oldfirst;
        N++;
    }
    public Item pop(){
        Item item = first.item;
        first = first.next;
        N--;
        return item;
    }
    //實現迭代
    public
 
 Iterator<Item> iterator(){
        return new ListIterator();
    }
    private class ListIterator implements Iterator<Item>{
        private Node current = first;
        public boolean hasNext(){
            return current != null;
        }
        public void remove(){}
        public
 
 Item next(){
            Item item = current.item;
            current = current.next;;
            return item;
        }
    }
}

（2）佇列（Queue）的實現

public class Queue<Item> implements Iterator<Item>{
    private Node first;
    private Node last;
    private int N;
    private class Node{
        Item item;
        Node next;
    }
//佇列向隊尾填加元素
    public void enqueue(Item item){
        Node oldlast = last;
        last = new Node();
        last.item = item;
        last.next = null;
        if(isEmpty) first = last;
        else oldlast.next = last;
        N++;
        return item;    
    }
    public Item dequeue(){
        Item item = first.item;
        first = first.next;
        if(isEmpty()) last = null;
        N--;
        return item;
    }    
}

（3）包（Bag）

public class Bag<Item>{
    private Node first;
    private int N;
    private class Node{
        Item item;
        Node next;
    }
    public void add(Item item){
        Node oldfirst = first;
        first = new Node();
        first.item = item;
        first.next = oldfiirst;
    }
}

順序儲存結構：陣列
優點：通過索引可以任意訪問元素
缺點：初始化時需要知道元素數量
鏈式儲存結構：連結串列
優點：使用的空間大小和元素數量成正比
缺點：需要通過引用訪問任意元素