mystack.java

java培训专题

package util;
import java.util.*;
public class MyStack {//双向链表
	private LinkedList ll=new LinkedList();
	public void push(Object o){
		ll.addFirst(o);
	}
	public void pop(){
		ll.removeFirst();//取出并移除栈顶元素.
	}
	public Object peek(){
		return ll.getFirst();//获得栈顶元素.
	}
	public boolean empty(){
		return ll.isEmpty();
	}
	public static void main(String[] args) {
		MyStack ms=new MyStack();
		ms.push("one");
		ms.push("two");
		ms.push("three");
		
		System.out.println(ms.peek());
		ms.pop();
		System.out.println(ms.peek());
		System.out.println(ms.empty());
		ms.pop();
		ms.pop();
		System.out.println(ms.empty());
		
	}

}