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copied!<p>You only get timeout behavior when you use blocking to get the results of the <code>Future</code>. If you want to use the non-blocking callbacks <code>onComplete</code>, <code>onSuccess</code> or <code>onFailure</code>, then you would have to roll your own timeout handling. Akka has built in timeout handling for request/response (<code>?</code>) messaging between actors, but not sure if you want to start using Akka. FWIW, in Akka, for timeout handling, they compose two <code>Futures</code> together via <code>Future.firstCompletedOf</code>, one which represents the actual async task and one that represents the timeout. If the timeout timer (via a <code>HashedWheelTimer</code>) pops first, you get a failure on the async callback.</p> <p>A very simplified example of rolling your own might go something like this. First, an object for scheduling timeouts:</p> <pre><code>import org.jboss.netty.util.{HashedWheelTimer, TimerTask, Timeout} import java.util.concurrent.TimeUnit import scala.concurrent.duration.Duration import scala.concurrent.Promise import java.util.concurrent.TimeoutException object TimeoutScheduler{ val timer = new HashedWheelTimer(10, TimeUnit.MILLISECONDS) def scheduleTimeout(promise:Promise[_], after:Duration) = { timer.newTimeout(new TimerTask{ def run(timeout:Timeout){ promise.failure(new TimeoutException("Operation timed out after " + after.toMillis + " millis")) } }, after.toNanos, TimeUnit.NANOSECONDS) } } </code></pre> <p>Then a function to take a Future and add timeout behavior to it:</p> <pre><code>import scala.concurrent.{Future, ExecutionContext, Promise} import scala.concurrent.duration.Duration def withTimeout[T](fut:Future[T])(implicit ec:ExecutionContext, after:Duration) = { val prom = Promise[T]() val timeout = TimeoutScheduler.scheduleTimeout(prom, after) val combinedFut = Future.firstCompletedOf(List(fut, prom.future)) fut onComplete{case result => timeout.cancel()} combinedFut } </code></pre> <p>Note that the <code>HashedWheelTimer</code> I am using here is from Netty.</p>

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