在容器中等待CountDownLatch的多个实例(Awaiting multiple instances of CountDownLatch in container)

 我写了一个类CountDownLatchContainer它有一个await()方法，它等待所有CountDownLatches。 一切工作正常。 
 
public final class CountDownLatchContainer
{
  private final Set<CountDownLatch> countDowns;

  public CountDownLatchContainer(List<CountDownLatch> countDowns)
  {
    this.countDowns = new HashSet<CountDownLatch>(countDowns);
  }

  public void await() throws InterruptedException
  {
    for (CountDownLatch count : countDowns)
      count.await();
  }
}
 
 为了科学和艺术（D），我想扩展功能，并从CountDownLatch类中添加public boolean await(long timeout, TimeUnit unit) 。 
 
 我希望每个倒数锁存器都具有相同的超时时间，并且总的方法只是为了阻塞timeout TimeUnits的数量。 实现这一点很困难。 我拥有的是： 
 
  public boolean await(long timeout, TimeUnit unit) throws InterruptedException
  {
    boolean success = true;
    for (CountDownLatch count : countDowns)
      success &= count.await(timeout / countDowns.size(), unit);
    return success;
  }
 
 所以，总体超时是照顾的，但每一次倒计时只占整个时间的百分比。 
 
 那么我怎样才能给单个锁存器提供与方法参数中指定的时间相同的时间量，而不会超过总时间？ 
 
 在这里可视化。 Thx为了ascii艺术灵感的六合一。 
 
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I wrote a class CountDownLatchContainer it has a await() method, that waits on all CountDownLatches. Everything is working fine.
 
public final class CountDownLatchContainer
{
  private final Set<CountDownLatch> countDowns;

  public CountDownLatchContainer(List<CountDownLatch> countDowns)
  {
    this.countDowns = new HashSet<CountDownLatch>(countDowns);
  }

  public void await() throws InterruptedException
  {
    for (CountDownLatch count : countDowns)
      count.await();
  }
}
 
For the sake of science and art (:D), I wanted to extend the functionality and add the public boolean await(long timeout, TimeUnit unit) from the CountDownLatch class.
 
I want each countdown latch to have the same timeout and the method overall just to block for the number of timeout TimeUnits. I have difficulties achieving that. What I have is:
 
  public boolean await(long timeout, TimeUnit unit) throws InterruptedException
  {
    boolean success = true;
    for (CountDownLatch count : countDowns)
      success &= count.await(timeout / countDowns.size(), unit);
    return success;
  }
 
So, the overall time out is taken care of, but each count down has just a percentage of the overall time. 
 
So how can I give the single latches the same amount of time as specified in the method parameter without execeeding the total time?
 
Here a visualization. Thx to hexafraction for the ascii art inspiration.
 
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原文：https://stackoverflow.com/questions/18663436