class ArrayStack {
    private int maxSize;//栈的大小
    private int[] stack;//用数组模拟栈，将数据放到数组中
    private int top = -1;//表示栈顶，默认值为 -1

    public ArrayStack(int maxSize) {
        this.maxSize = maxSize;
        stack = new int[maxSize];
    }

    //栈满
    public boolean isFull() {
        return top == maxSize - 1;
    }
    //栈空
    public boolean isEmpty() {
        return top == -1;
    }
}

入栈

//入栈-push
    public void push(int value) {
        //先判断栈是否为满
        if(isFull()) {
            System.out.println("栈满");
            return;
        }
        stack[++top] = value;
    }

出栈

//出栈-pop，将栈顶的数据返回
    public int pop() {
        //先判断栈是否为空
        if(isEmpty()) {
//            System.out.println("栈空");
//            return;
        // 因为有返回值，所以不能用这种返回的方式
        throw new RuntimeException("栈空");
        }
        int value = stack[top--];
        return value;
    }

显示栈

//显示栈的情况（遍历栈），遍历时，需要从栈顶开始显示数据
    public void list() {
        //判断栈是否为空
        if(isEmpty()) {
            System.out.println("栈空");
            return;
        }
        //从栈顶开始显示数据
        for (int i = top; i >= 0; i--) {
            System.out.printf("stack[%d] = %d\n",i,stack[i]);
        }
    }

编写ArrayStackDemo类，演示数组模拟栈

import java.util.Scanner;
//用数组表示栈
public class ArrayStackDemo {
    public static void main(String[] args) {
        ArrayStack arrayStack = new ArrayStack(5);
        boolean loop = true;//控制是否退出菜单
        Scanner scanner = new Scanner(System.in);

        while(loop) {
            System.out.println("push：入栈");
            System.out.println("pop：出栈");
            System.out.println("show：显示栈");
            System.out.println("exit：退出程序");

            System.out.println("请输入你的选择：");
            String key = scanner.next();

            switch (key) {
                case "push":
                    System.out.println("请输入一个数：");
                    int value = scanner.nextInt();
                    arrayStack.push(value);
                    break;
                case "pop":
                    try {
                        int res = arrayStack.pop();//抛出异常
                        System.out.println("出栈的数据为：" + res);
                    } catch (Exception e) {
                        System.out.println(e.getMessage());
                    }
                    break;
                case "show":
                    arrayStack.list();
                    break;
                case "exit":
                    scanner.close();//关闭scanner
                    loop = false;
                    break;
                default:
                    break;
            }
        }
        System.out.println("程序以及结束");
    }
}