Question

所有

我编写了以下简单代码来测试scala.actors ._：

// java version "1.7.0_02"
// Scala code runner version 2.9.1.final
// Windows 7 Ultimate sp1 64-bit
import scala.actors._
import scala.collection.mutable.ArrayBuffer

object FutureResults extends App {
    val t1 = System.currentTimeMillis
    val (timeout, results) = (1000, new ArrayBuffer[Future[_]])
    for (i <- 0 until 3) results += new FutureResultsActor !! "execute"
    val options = Futures awaitAll (timeout, results:_*)

    val t2 = System.currentTimeMillis
    println("spent: %,d ms" format t2 - t1)
    options foreach println
    results foreach { i => println("isSet: %b" format i.isSet) }

    Thread sleep timeout

    val t3 = System.currentTimeMillis
    println("spent: %,d ms" format t3 - t1)
    options foreach println
    results foreach { i => println("isSet: %b" format i.isSet) }
}

class FutureResultsActor extends Actor {
    start
    override def act = react { case "execute" => Futures future "done" }
}

这会产生：

spent: 1,092 ms
None
None
None
isSet: false
isSet: false
isSet: false

spent: 2,137 ms
None
None
None
isSet: false
isSet: false
isSet: false

期货的Scaladoc＃awaitAll说：

The result of a future that resolved during the time span is its value wrapped in Some.
The result of a future that did not resolve during the time span is None.

超时值是否太小？好的，我将值更改为5000毫秒，然后重试：

spent: 5,070 ms
None
None
None
isSet: false
isSet: false
isSet: false

spent: 10,093 ms
None
None
None
isSet: false
isSet: false
isSet: false

全部都是无。为什么呢？......

如何从期货结果中获得一些（x）＃awaitAll？

是否有错误的代码？

Answer 1

确实，他们都已超时了。相当悲剧！原因是：你没有发送演员的回复 - 或者至少不正确。我不太确定“期货未来”是什么，但是......我的理解是，在演员中回答的正确方法是这样的：

class FutureResultsActor extends Actor {
  start
  override def act = react { case "execute" => reply("done") } // Use reply()!
}

这样做了我的结果：

spent: 150 ms
Some(done)
Some(done)
Some(done)
isSet: true
isSet: true
isSet: true
spent: 1,165 ms
Some(done)
Some(done)
Some(done)
isSet: true
isSet: true
isSet: true

如何从期货＃awaitAll的结果中得到一些（x）？

1 个答案: