需求

代码

• 使用Callable 方便返回执行的结果：每个线程的发送礼物的数量
• 礼物清单：共享资源，方便上锁
• 礼物数量：线程变量，每个线程发送礼物的数量

java">public class SendGiftThread implements Callable<Integer> {// 共享资源 礼物清单private ArrayList<String> giftList;// 此线程已经送出的礼物数量private int count = 0;public SendGiftThread(ArrayList<String> giftList) {this.giftList = giftList;}public int getCount() {return count;}@Overridepublic Integer call() throws Exception {Random random = new Random();while (giftList.size() > 10){// 锁住的不一定是this，一定要是共享资源synchronized (giftList){// 礼物大于10个时，随机送出一个礼物if (giftList.size() > 10){int index = random.nextInt(giftList.size());// 送出礼物String remove = giftList.remove(index);// 送出礼物数量+1count++;System.out.println(Thread.currentThread().getName() + "送出了" + remove + "，已送出" + count + "个礼物");}}}return count;}
}

• 创建两个Callable对象
• 使用未来任务FutureTask进行封装
• 创建两个线程

java">public static void main(String[] args) {// 随机生成100个礼物ArrayList<String> giftList = new ArrayList<>();String[] names = {"口红", "手机", "电脑", "手表", "鞋子", "衣服", "裤子", "帽子", "围巾", "手套", "袜子", "饰品", "包包", "眼镜", "钱包", "皮带", "项链", "手链", "戒指", "耳环"};Random random = new Random();for (int i = 0; i < 100; i++) {giftList.add(names[random.nextInt(names.length)]+"-"+i);}// 创建两个任务SendGiftThread sendGiftThread1 = new SendGiftThread(giftList);SendGiftThread sendGiftThread2 = new SendGiftThread(giftList);Future<Integer> future1 = new FutureTask<>(sendGiftThread1);Future<Integer> future2 = new FutureTask<>(sendGiftThread2);// 创建两个线程Thread thread1 = new Thread((Runnable) future1, "小红");Thread thread2 = new Thread((Runnable) future2, "小明");// 启动线程thread1.start();thread2.start();// 打印线程返回结果try {System.out.println("小红送出了" + future1.get() + "个礼物");System.out.println("小明送出了" + future2.get() + "个礼物");} catch (Exception e) {e.printStackTrace();}}