要求:可以通過ArrayList或LinkedList介面完成佇列的建立，可以實現入隊、出隊等操作。新定義類利用多執行緒的思想完成買票和賣票的同步操作。

程式碼：

import java.util.ArrayList;
import java.util.EmptyStackException;
import java.util.LinkedList;
import java.util.List;

class Goods {
    private String goodsName;//商品名稱
    MyQueue q = new MyQueue();
    public synchronized void setGoods(String goodsName) {//生產商品方法
        //當前還有商品需要等待消費者消費後才生產
        while (q.size() > 0){
            try {
                System.out.println("正在售票。。。");
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        try {
            Thread.sleep(200);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        this.goodsName = goodsName;
        q.add("票");
        System.out.println(Thread.currentThread().getName()+"生產" + toString());
        //生產完後喚醒
        notifyAll();
    }

    public synchronized void getGoods() {//消費商品方法
        while (q.size() == 0){
            try {
                System.out.println("賣完了。");
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        try {
            Thread.sleep(200);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        try {
            Thread.sleep(200);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        q.remove();
        System.out.println(Thread.currentThread().getName()+"消費" + toString());
        //消費完後，告訴生產者生產
        notifyAll();
    }

    @Override
    public String toString() {
        return "Goods{" + "goodsName='" + goodsName + '\'' + ", count=" + q.size() + '}';
    }
}

//生產者
class Producer implements Runnable {
    private Goods goods;

    public Producer(Goods goods) {
        this.goods = goods;
    }

    public void run() {
        while (true) {
            this.goods.setGoods("生產票");
        }
    }
}

//消費者
class Consumer implements Runnable {
    private Goods goods;

    public Consumer(Goods goods) {
        this.goods = goods;
    }

    public void run() {
        while (true) {
            this.goods.getGoods();
        }
    }
}

class MyQueue {
    private LinkedList<Object> link = new LinkedList<Object>();

    public MyQueue() {

    }

    public void add(Object obj) {//新增元素
        link.addLast(obj);
    }

    public Object remove() {//刪除元素
        if (isEmpty()) {
            throw new EmptyStackException();
        }
        return link.removeFirst();
    }
    public int size(){//求長度
        return link.size();
    }
    public boolean isEmpty() {//判斷是不是空
        return link.isEmpty();
    }
    public void clear() {//清空
        link.clear();
    }
}

public class Queue {
    public static void main(String[] args) {
        Goods goods = new Goods();
        //儲存生產消費者執行緒
        List<Thread> list = new ArrayList<>();
        Producer producer = new Producer(goods);
        Consumer consumer = new Consumer(goods);
        for(int i= 0;i<5;i++){
            Thread thread = new Thread(producer,"生產者"+i);
            list.add(thread);
        }
        for (int i = 0;i<10;i++){
            Thread thread = new Thread(consumer,"消費者"+i);
            list.add(thread);
        }
        for (Thread thread:list) {
            thread.start();
        }
    }
}