Java Scheduled Executor Service等待所有线程完成

Question

ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(4);
for (int i = 0; i < 4; i++)
{Runnable autoUpdate = new autoUpdateWork(i);
ScheduledFuture<?> scheduleAtFixedRate = scheduler.scheduleAtFixedRate(autoUpdate, 0, 60, TimeUnit.SECONDS);
}
if (scheduleAtFixedRate != null)
    {    
        while(!scheduleAtFixedRate.isDone())
        //wait...
    }
//PointA :until all threads are finished, do sth, then invoke the scheduled task with 60 sec interval    again.

到目前为止，上面是我的代码。但似乎它永远不会到达PointA ..请帮助，谢谢！

Answer 1

而不是

if (scheduleAtFixedRate != null)
{    
    while(!scheduleAtFixedRate.isDone())
    //wait...
}

在Runnable类中添加一个volatile变量，如下所示。

public  volatile boolean isRunning = false;

一旦你的线程完成了工作，将其更改为true，并在你的检查部分中添加。

while(!autoUpdate.isRunning);