zip

Combines elements from each of multiple sources into tuples and passes the tuples downstream.

Fan-in operators

Signature

Source.zip Flow.zip

Description

Combines elements from each of multiple sources into tuples and passes the tuples downstream.

See also:

Examples

Scala
Java
sourceimport org.apache.pekko
import pekko.stream.scaladsl.Source
import pekko.stream.scaladsl.Sink

    val sourceFruits = Source(List("apple", "orange", "banana"))
    val sourceFirstLetters = Source(List("A", "O", "B"))
    sourceFruits.zip(sourceFirstLetters).runWith(Sink.foreach(println))
    // this will print ('apple', 'A'), ('orange', 'O'), ('banana', 'B')
sourceimport org.apache.pekko.stream.javadsl.Keep;
import org.apache.pekko.stream.javadsl.Source;
import org.apache.pekko.stream.javadsl.Sink;

import java.util.*;

Source<String, NotUsed> sourceFruits = Source.from(Arrays.asList("apple", "orange", "banana"));
Source<String, NotUsed> sourceFirstLetters = Source.from(Arrays.asList("A", "O", "B"));
sourceFruits.zip(sourceFirstLetters).runForeach(System.out::println, system);
// this will print ('apple', 'A'), ('orange', 'O'), ('banana', 'B')

Reactive Streams semantics

emits when both of the inputs have an element available

backpressures both upstreams when downstream backpressures but also on an upstream that has emitted an element until the other upstream has emitted an element

completes when either upstream completes

1.1.3