栈的实现
栈的实现：
import java.io.*;//栈中的每个节点class Element{//指向下一个节点private Element next;//节点中的对象private Object value;public Element getNext() {return next;}public Object getValue() {return value;}public Element(){this.next=null;this.value=null;}//构造方法public Element(Element next,Object value){this.next=next;this.value=value;}}//栈结构public class MyStack { //指向最顶的栈节点 Element top; //栈中节点个数 int count; //初始化栈 public MyStack() { this.top=null; count=0; } //压入 public void push(Object value) { Element e=new Element(this.top,value); this.count++; this.top=e; } //弹出 public Object pop() { Element e=this.top; if(this.top!=null) { this.count--; this.top=this.top.getNext(); return e.getValue(); } else return null; } //查看栈顶节点 public Object get_top() { if(this.top!=null) { return this.top.getValue(); } else { return null; } } //栈中节点数 public int get_count() { return this.count; } public static void main(String args[]) { MyStack s=new MyStack(); Integer i=new Integer("1"); String j=new String("2345abcdej"); s.push(i); s.push(j); System.out.println("栈节点数:"+s.get_count()); System.out.println("查看栈顶:"+s.get_top()); System.out.println("弹出栈顶:"+s.pop()); System.out.println("---------------------------"); System.out.println("栈节点数:"+s.get_count()); System.out.println("查看栈顶:"+s.get_top()); System.out.println("弹出栈顶:"+s.pop()); System.out.println("---------------------------"); System.out.println("栈节点数:"+s.get_count()); System.out.println("查看栈顶:"+s.get_top()); System.out.println("弹出栈顶:"+s.pop()); System.out.println("---------------------------"); }}?