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我按以下顺序放置了两个 Promise，并在收到 Promise 后立即将 Promise 映射到字符串结果。第二个承诺结果将无法返回。该错误仅发生在第二个承诺映射中。这是在 Play 2.1 Java 下进行的测试。有没有更好的方法来解决这个问题？

    Promise<String> prom1 = Akka.future(new Callable<String>() {
        public String call() {
            // intensive computation
            return "prom1 ret";
        }
    });
    Promise<String> prom2 = Akka.future(new Callable<String>() {
        public String call() {
            // intensive computation
            return "prom2 ret";
        }
    });
    String ret1 = prom1.map(
            new Function<String,String>() {
              public String apply(String str) {
                  return str + " affix";
              }
            }
          ).get();
    String ret2 = prom2.map(
            new Function<String,String>() {
                public String apply(String str) {
                    return str + " affix";
                }
              }
          ).get();

我得到的例外：

play.api.Application$$anon$1: Execution exception[[RuntimeException: java.util.concurrent.TimeoutException: Futures timed out after [10000 milliseconds]]]
    at play.api.Application$class.handleError(Application.scala:289) ~[play_2.10-2.1.0.jar:2.1.0]
    at play.api.DefaultApplication.handleError(Application.scala:383) [play_2.10-2.1.0.jar:2.1.0]
    at play.core.server.netty.PlayDefaultUpstreamHandler$$anon$2$$anonfun$handle$1.apply(PlayDefaultUpstreamHandler.scala:132) [play_2.10-2.1.0.jar:2.1.0]
    at play.core.server.netty.PlayDefaultUpstreamHandler$$anon$2$$anonfun$handle$1.apply(PlayDefaultUpstreamHandler.scala:128) [play_2.10-2.1.0.jar:2.1.0]
    at play.api.libs.concurrent.PlayPromise$$anonfun$extend1$1.apply(Promise.scala:113) [play_2.10-2.1.0.jar:2.1.0]
    at play.api.libs.concurrent.PlayPromise$$anonfun$extend1$1.apply(Promise.scala:113) [play_2.10-2.1.0.jar:2.1.0]
java.lang.RuntimeException: java.util.concurrent.TimeoutException: Futures timed out after [10000 milliseconds]
    at play.libs.F$Promise$6.apply(F.java:401) ~[play_2.10-2.1.0.jar:2.1.0]
    at scala.concurrent.Future$$anonfun$map$1.liftedTree2$1(Future.scala:253) ~[scala-library.jar:na]
    at scala.concurrent.Future$$anonfun$map$1.apply(Future.scala:249) ~[scala-library.jar:na]
    at scala.concurrent.Future$$anonfun$map$1.apply(Future.scala:249) ~[scala-library.jar:na]
    at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:29) ~[scala-library.jar:na]
    at akka.dispatch.BatchingExecutor$Batch$$anonfun$run$1.liftedTree1$1(BatchingExecutor.scala:67) ~[akka-actor_2.10-2.1.0.jar:na]
Caused by: java.util.concurrent.TimeoutException: Futures timed out after [10000 milliseconds]
    at scala.concurrent.impl.Promise$DefaultPromise.ready(Promise.scala:96) ~[scala-library.jar:na]
    at scala.concurrent.impl.Promise$DefaultPromise.ready(Promise.scala:58) ~[scala-library.jar:na]
    at scala.concurrent.Await$$anonfun$ready$1.apply(package.scala:86) ~[scala-library.jar:na]
    at scala.concurrent.Await$$anonfun$ready$1.apply(package.scala:86) ~[scala-library.jar:na]
    at akka.dispatch.MonitorableThreadFactory$AkkaForkJoinWorkerThread$$anon$3.block(ThreadPoolBuilder.scala:173) ~[akka-actor_2.10-2.1.0.jar:na]
    at scala.concurrent.forkjoin.ForkJoinPool.managedBlock(ForkJoinPool.java:2803) ~[scala-library.jar:na]
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