Java:当线程池中的所有线程都完成时通知主类/不同线程中的相同对象实例

Question

当 ThreadPoolExecutor 中的所有线程都完成时，如何通知实例化 ThreadPoolExecutor 的主类？

ThreadPoolExecutor threadPool = null;
ThreadClass threadclass1;
ThreadClass threadclass2;
final ArrayBlockingQueue<Runnable> queue = new ArrayBlockingQueue<Runnable>(maxPoolSize);

puclic MyClass(){
        threadPool = new ThreadPoolExecutor(poolSize, maxPoolSize, keepAliveTime, TimeUnit.SECONDS, queue);

        threadClass1 = new ThreadClass;
        threadClass2 = new ThreadClass;

        threadPool.execute(threadClass1);
        threadPool.execute(threadClass2);

        //Now I would like to do something until the threadPool is done working
        //The threads fill a ConcurrentLinkedQueueand I would like to poll
        //the queue as it gets filled by the threads and output 
        //it to XML via JAX-RS

}

编辑 1

我的线程从某处获取数据并将此信息填充到 ConcurrentLinkedQueue 中，我基本上想在 MyClass 中执行一些操作以使用结果更新 XML 输出。当所有线程都终止时，我想返回 true 到实例化 MyClass 的 JAX-RS web 服务，以便 web 服务知道所有数据都已被获取，它现在可以显示最终的 XML 文件

编辑2

我正在将一个Queue 传递给线程，这样它们就可以将项目添加到队列中。当一个 driver 完成向 articleQueue 添加项目时，我想在我的主类中执行一个操作，从 Queue 轮询实体并处理它传递给 response 对象以某种方式显示它。

当我将队列传递给线程时，它们是使用同一个对象还是使用对象的“副本”，以便线程内的更改不会影响主对象？那不是我想要的行为。当我检查 Driver 中 articleQueue 的大小时，它是 18，articleQueue 的大小在DriverController 为 0。

除了我的 while 循环，当一个线程向队列中添加了一些东西时，有没有更好的 react 方式？我必须如何修改我的代码才能访问不同类中的同一对象？

驱动 Controller

public class DriverController {

    Queue<Article> articleQueue;

    ThreadPoolExecutor threadPool = null;
    final ArrayBlockingQueue<Runnable> queue = new ArrayBlockingQueue<Runnable>(
            maxPoolSize);

    public DriverController(Response response) {

        articleQueue = new ConcurrentLinkedQueue<Article>();
        threadPool = new ThreadPoolExecutor();
        Driver driver = new Driver(this.articleQueue);

        threadPool.execute(driver);
        // More drivers would be executed here which add to the queue

        while (threadPool.getActiveCount() > 0) {
            // this.articleQueue.size() gives back 0 here ... why?
            if(articleQueue.size()>0){
                response.addArticle(articleQueue.poll());
            }
        }

    }
}

司机

public class Driver implements Runnable{

    private Queue<Article> articleQueue;

    public DriverAlliedElectronics(Queue articleQueue) {
        this.articleQueue = articleQueue;
    }

    public boolean getData() {
        // Here would be the code where the article is created ...

        this.articleQueue.offer(article);
        return true;
    }

    public void run() {
        this.getData();
        // this.articleQueue.size() gives back 18 here ...

    }
}

Answer 1

您应该尝试使用以下代码段

//Now I would like to wait until the threadPool is done working
threadPool.shutdown();
while (!threadPool.isTerminated()) {
    try {
        threadPool.awaitTermination(10, TimeUnit.MILLISECONDS);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}