Package org.apache.pekko.stream.javadsl

Class MergeSequence$

java.lang.Object

org.apache.pekko.stream.javadsl.MergeSequence$

public class MergeSequence$
extends java.lang.Object

Takes multiple streams whose elements in aggregate have a defined linear sequence with difference 1, starting at 0, and outputs a single stream containing these elements, in order. That is, given a set of input streams with combined elements *e_k*:

*e₀*, *e₁*, *e₂*, ..., *e_n*

This will output a stream ordered by *k*.

The elements in the input streams must already be sorted according to the sequence. The input streams do not need to be linear, but the aggregate stream must be linear, no element *k* may be skipped or duplicated, either of these conditions will cause the stream to fail.

The typical use case for this is to merge a partitioned stream back together while maintaining order. This can be achieved by first using zipWithIndex on the input stream, then partitioning using a Partition fanout, and then maintaining the index through the processing of each partition before bringing together with this stage.

'''Emits when''' one of the upstreams has the next expected element in the sequence available.

'''Backpressures when''' downstream backpressures

'''Completes when''' all upstreams complete

'''Cancels when''' downstream cancels

Field Summary

Fields

Modifier and Type	Field	Description
static MergeSequence$	MODULE$	Static reference to the singleton instance of this Scala object.

Constructor Summary

Constructors

Constructor	Description
MergeSequence$()

Method Summary

Modifier and Type	Method	Description
<T> Graph<UniformFanInShape<T,T>,NotUsed>	create(int inputCount, Function<T,java.lang.Object> extractSequence)	Create a new anonymous MergeSequence operator.
<T> Graph<UniformFanInShape<T,T>,NotUsed>	create(java.lang.Class<T> clazz, int inputCount, Function<T,java.lang.Object> extractSequence)	Create a new anonymous Concat operator with the specified input types.
<T> Graph<UniformFanInShape<T,T>,NotUsed>	create(Function<T,java.lang.Object> extractSequence)	Create a new anonymous MergeSequence operator with two input ports.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MODULE$

public static final MergeSequence$ MODULE$

Static reference to the singleton instance of this Scala object.

Constructor Detail

MergeSequence$

public MergeSequence$()

Method Detail

create

public <T> Graph<UniformFanInShape<T,T>,NotUsed> create(Function<T,java.lang.Object> extractSequence)

Create a new anonymous MergeSequence operator with two input ports.

Parameters:

extractSequence - The function to extract the sequence from an element.

create

public <T> Graph<UniformFanInShape<T,T>,NotUsed> create(int inputCount,
                                                                    Function<T,java.lang.Object> extractSequence)

Create a new anonymous MergeSequence operator.

Parameters:

inputCount - The number of input streams.

extractSequence - The function to extract the sequence from an element.

create

public <T> Graph<UniformFanInShape<T,T>,NotUsed> create(java.lang.Class<T> clazz,
                                                                    int inputCount,
                                                                    Function<T,java.lang.Object> extractSequence)

Create a new anonymous Concat operator with the specified input types.

Parameters:

clazz - a type hint for this method

inputCount - The number of input streams.

extractSequence - The function to extract the sequence from an element.