akka.stream.impl.JavaStreamSource.scala Maven / Gradle / Ivy
/*
* Copyright (C) 2018-2020 Lightbend Inc.
*/
package akka.stream.impl
import akka.stream._
import akka.stream.stage.{ GraphStage, GraphStageLogic, OutHandler }
import akka.annotation.InternalApi
/** INTERNAL API */
@InternalApi private[stream] final class JavaStreamSource[T, S <: java.util.stream.BaseStream[T, S]](
open: () => java.util.stream.BaseStream[T, S])
extends GraphStage[SourceShape[T]] {
val out: Outlet[T] = Outlet("JavaStreamSource")
override val shape: SourceShape[T] = SourceShape(out)
override def createLogic(inheritedAttributes: Attributes): GraphStageLogic =
new GraphStageLogic(shape) with OutHandler {
private[this] var stream: java.util.stream.BaseStream[T, S] = _
private[this] var iter: java.util.Iterator[T] = _
setHandler(out, this)
override def preStart(): Unit = {
stream = open()
iter = stream.iterator()
}
override def postStop(): Unit = {
if (stream ne null)
stream.close()
}
override def onPull(): Unit = {
if (iter.hasNext) {
push(out, iter.next())
} else {
complete(out)
}
}
}
}