无法解析方法问--Akka Streaming with Java

Fed*_*enz 2 java akka akka-stream

我正在试验akka,并且(在文档之后),我有以下代码:

Source<String, NotUsed> words =
                Source.from(Arrays.asList("hello", "hi"));
        Timeout askTimeout = Timeout.apply(5, TimeUnit.SECONDS);

        words
                .mapAsync(5, elem -> ask(ref, elem, askTimeout))
                .map(elem -> (String) elem)
                // continue processing of the replies from the actor
                .map(elem -> elem.toLowerCase())
                .runWith(Sink.ignore(), materializer);
Run Code Online (Sandbox Code Playgroud)

但是我找不到"import static"指令来使"ask方法"起作用.我有:

无法解决方法问

我做错了什么?我正在使用akka v 2.4(使用Java,没有Scala)并按照以下步骤逐步完成文档:http: //doc.akka.io/docs/akka/2.4/java/stream/stream-integrations.html

谢谢.

dfo*_*gni 5

ask是指询问模式.

你可以在java中使用它 import static akka.pattern.Patterns.ask