问如何将源[ByteString，Any]转换为InputStream

EN

import akka.stream.scaladsl.StreamConverters
...
val inputStream: InputStream = entity.dataBytes
        .runWith(
           StreamConverters.asInputStream(FiniteDuration(3, TimeUnit.SECONDS))
        )

import akka.util.ByteString
import akka.stream.scaladsl.Source
import java.io.PipedInputStream
import java.io.PipedOutputStream
import akka.stream.io.OutputStreamSink
import java.io.BufferedReader
import java.io.InputStreamReader
import akka.actor.ActorSystem
import akka.stream.ActorFlowMaterializer

object PipedStream extends App{
  implicit val system = ActorSystem("flowtest")
  implicit val mater = ActorFlowMaterializer()

  val lines = for(i <- 1 to 100) yield ByteString(s"This is line $i\n")
  val source = Source(lines)

  val pipedIn = new PipedInputStream()
  val pipedOut = new PipedOutputStream(pipedIn)      
  val flow = source.to(OutputStreamSink(() => pipedOut))
  flow.run()

  val reader = new BufferedReader(new InputStreamReader(pipedIn))
  var line:String = reader.readLine
  while(line != null){
    println(s"Reader received line: $line")
    line = reader.readLine
  }           
}