队列记录

import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Stack;
import java.util.concurrent.ArrayBlockingQueue;

public class quit {
    
    
    public static void main(String[] args) {
    
    
        //后进先出
        //Stack<String> stackstr = new Stack<>();
        先进先出
        Queue<String> queue = new ArrayBlockingQueue<>(12 * 48 + 12);

        queue.add("1236");
        queue.add("1235");
        queue.add("1234");
        queue.remove("1236");


        System.out.println(queue.poll());
        System.out.println(queue.poll());
        System.out.println(queue.poll());

        //后进先出
        Stack<Integer> stack = new Stack<>();
        //压栈
        stack.push(1);
        stack.push(2);
        stack.push(3);
        stack.push(4);

        //stack.remove(3);
        //查看栈顶元素
        System.out.println(stack.peek());

        //出栈
        int ret = stack.pop();
        System.out.println(ret);  //4
        ret = stack.pop();
        System.out.println(ret);  //3
        ret = stack.pop();
        System.out.println(ret);  //2
        ret = stack.pop();
        System.out.println(ret);  //1
        //判断栈是否为空
        System.out.println(stack.empty());
        //此时栈为空 如果 查看栈顶元素 或者 出栈 会报异常(EmptyStackException)
        System.out.println(stack.peek());
        System.out.println(stack.pop());

    }
}

运行结果

1235
1234
null
4
4
3
2
1
true
Exception in thread "main" java.util.EmptyStackException
	at java.util.Stack.peek(Stack.java:102)
	at zhen.qi.text.quit.main(quit.java:49)

Process finished with exit code 1