abstract class Istackint MAX_SIZE = 5; 最大栈长度。为5表示栈中最大容纳5个元素public abstract boolean pushint data; 元素进栈如果栈满返回falsepublic abstract int pop; 从栈中取数据。如果栈已为空返回IntegerMIN_VALUEpublic abstract boolean isEmpty;

public class Stack extends Istack{ private int[] data; //栈中存储数据的数组 private int top; //栈顶指针，指向栈顶元素的下标

public Stack(){
    data = new int[MAX_SIZE]; //初始化数组大小
    top = -1; //栈顶指针初始化为-1，表示栈为空
}

@Override
public boolean push(int data) {
    if(top == MAX_SIZE-1){ //判断栈是否已满
        return false;
    }
    this.data[++top] = data; //栈顶指针加1，并将元素存入栈中
    return true;
}

@Override
public int pop() {
    if(top == -1){ //判断栈是否为空
        return Integer.MIN_VALUE;
    }
    int result = this.data[top--]; //取出栈顶元素，并将栈顶指针减1
    return result;
}

@Override
public boolean isEmpty() {
    return (top == -1); //判断栈是否为空
}

@Override
public void display() {
    if(isEmpty()){
        System.out.println("栈为空");
    }else{
        System.out.print("栈中元素有:");
        for(int i=0; i<=top; i++){
            System.out.print(this.data[i] + " ");
        }
        System.out.println();
    }
}

}

//测试代码 public static void main(String[] args) { System.out.println("栈测试开始"); Stack stack = new Stack(); int v = stack.pop(); if(v == Integer.MIN_VALUE){ System.out.println("弹出失败，栈为空"); }else{ System.out.println("弹出数据为:" + v); } stack.display(); stack.push(1); stack.push(2); stack.push(3); stack.push(4); stack.push(5); if(!stack.push(6)){ System.out.println("压栈失败，栈已满。失败的数据为：6"); stack.display(); } for(int i=0; ; i++){ if(stack.isEmpty()) break; System.out.println(i + ". 弹出元素为:" + stack.pop()); stack.display(); } System.out.println("栈测试结束");