interleave

Emits a specifiable number of elements from the original source, then from the provided source and repeats.

Fan-in operators

Signature

Source.interleaveSource.interleave Flow.interleaveFlow.interleave

Description

Emits a specifiable number of elements from the original source, then from the provided source and repeats. If one source completes the rest of the other stream will be emitted.

Example

Scala

copysourceimport akka.stream.scaladsl.Sink
import akka.stream.scaladsl.Source

val sourceA = Source(List(1, 2, 3, 4))
val sourceB = Source(List(10, 20, 30, 40))

sourceA.interleave(sourceB, segmentSize = 2).runWith(Sink.foreach(println))
//prints 1, 2, 10, 20, 3, 4, 30, 40

Java

copysourceimport akka.stream.javadsl.Keep;
import akka.stream.javadsl.Source;
import akka.stream.javadsl.Sink;

import java.util.*;

Source<Integer, NotUsed> sourceA = Source.from(Arrays.asList(1, 2, 3, 4));
Source<Integer, NotUsed> sourceB = Source.from(Arrays.asList(10, 20, 30, 40));
sourceA.interleave(sourceB, 2).runForeach(System.out::println, system);
// prints 1, 2, 10, 20, 3, 4, 30, 40

Reactive Streams semantics