java操作链栈

链栈类代码
package linkedstack;

public class LinkStack {

private Element base;
private Element top;
 
class Element
{
    public Object data;
    public Element next;
}
 
/**
 * 初始化栈
 * */
void initStack()
{
    top = new Element();
    base = new Element();
    top.data=null;
    top.next=base;
    base.data=null;
    base.next=null;
}
 
/**
 * 入栈
 * */
void push(Object o)
{
    Element e = new Element();
    e.data = o;
    if(top.next==base)//第一次入栈操作
    {
        e.next=base;
        top.next=e;
    }else
    {
        e.next=top.next;
        top.next=e;
    }
     
}
 
/**
 * 出栈
 * */
void pop()
{
    if(top.next==base)
    {
        System.out.println("栈中没有元素！");
    }else
    {
        System.out.println("出栈操作"+top.next.data);
        top.next=top.next.next;
    }
}
 
/**
 * 打印栈
 * */
void print()
{
    System.out.print("打印栈：");
    Element temp =top;
    while(temp.next!=base)
    {
        System.out.print(temp.next.data+"\t");
        temp =temp.next;
    }
    System.out.println();
}

}
测试
package linkedstack;

public class LinkStackMain {

public static void main(String[] args) {
    LinkStack lStack = new LinkStack();
    lStack.initStack();
    lStack.pop();
    lStack.push(1);
    lStack.push(2);
    lStack.push(3);
    lStack.push(4);
    lStack.print();
     
    lStack.pop();
    lStack.pop();
    lStack.print();
     
    lStack.pop();
    lStack.pop();
    lStack.print();
    lStack.pop();
}

}