用LinkedList模拟栈数据结构的集合并测试

/*
 *需求：请用LinkedList模拟栈数据结构的集合，并测试
 *创建一个类将Linked中的方法封装
 */
public class Demo4_LinkedList {
    public static void main(String[] args) {
        Stack stack = new Stack();
        stack.in("a");
        stack.in("b");
        stack.in("c");
        stack.in("d");
        while (!stack.isEmpty()) {
            System.out.println(stack.out());
        }
    }
}

import java.util.LinkedList;

public class Stack {
    @SuppressWarnings("rawtypes")
    private LinkedList list = new LinkedList();

    @SuppressWarnings("unchecked")
    public void in(Object obj) {// 模拟进栈
        list.addLast(obj);
    }

    public Object out() {// 模拟出栈
        return list.removeLast();
    }

    public boolean isEmpty() {// 判断是否为空
        return list.isEmpty();
    }