java - 为什么 invokeAll() 不返回？

Question

我大概有这样的代码:

ExecutorService threader = Executors.newFixedThreadPool(queue.size());
List futures = threader.invokeAll(queue);

我对此进行了调试，直到队列中的所有线程都完成后，invokeAll 似乎才返回。发生这种情况的任何原因。

Answer 1

Executes the given tasks, returning a list of Futures holding their status and results when all complete. the API

您必须一次一个地提交()它们，例如:

public static <T> List<Future<T>> submitAll ( ExecutorService executor, Collection<? extends Callable<T> > tasks ) {
    List<Future<T>> result = new ArrayList<Future<T>>( tasks.size() );

    for ( Callable<T> task : tasks )
        result.add ( executor.submit ( task ) );

    return result;
}