使用静态内部类充当单链表
1 package db;
2
3 /**
4 * 只有头结点实现栈
5 *
6 * @author fightzhao
7 *
8 */
9 public class Stack<E> {
10 /*
11 * 有以下方法 入栈 push(E x) 出栈pop() 栈顶元素top()
12 */
13 private static class Node<E> {
14 public Node<E> next;
15 public E data;
16
17 public Node(E data, Node<E> next) {
18 this.data = data;
19 this.next = next;
20 }
21 }
22
23 private Node<E> head;
24 private int theSize;
25
26 public Stack() {
27 head = null;
28 }
29
30 public int size() {
31 return theSize;
32 }
33
34 public void push(E data) {
35 Node<E> pNode = new Node<E>(data, head);
36 head = pNode;
37 theSize++;
38 }
39
40 public void pop() {
41 head = head.next;
42 theSize--;
43 }
44
45 public E top() {
46 return head.data;
47 }
48
49 public void printAll() {
50 Node<E> pNode = head;
51 while (pNode != null) {
52 System.out.println(pNode.data);
53 pNode = pNode.next;
54 }
55
56 }
57 }
