com.hazelcast.jet.pipeline

Class WindowGroupAggregateBuilder1<T0,K>

java.lang.Object

com.hazelcast.jet.pipeline.WindowGroupAggregateBuilder1<T0,K>

Type Parameters:

T0 - the type of the stream-0 item

K - type of the key

public class WindowGroupAggregateBuilder1<T0,K>
extends Object

Offers a step-by-step API to build a pipeline stage that performs a windowed co-grouping and aggregation of the data from several input stages. To obtain it, call StageWithKeyAndWindow.aggregateBuilder() on one of the stages to co-aggregate and refer to that method's Javadoc for further details.

This object is mainly intended to build a co-aggregation of four or more contributing stages. For up to three stages, prefer the direct stage.aggregateN(...) calls because they offer more static type safety.

Note: this is not a builder of AggregateOperation. If that' s what you are looking for, go here.

Since:

Jet 3.0

Method Summary

Modifier and Type	Method and Description
<T> Tag<T>	add(StreamStageWithKey<T,K> stage) Adds another stage that will contribute its data to the windowed group-and-aggregate stage being constructed.
<R> StreamStage<KeyedWindowResult<K,R>>	build(AggregateOperation<?,? extends R> aggrOp) Creates and returns a pipeline stage that performs a windowed cogroup-and-aggregate of the pipeline stages registered with this builder object.
Tag<T0>	tag0() Returns the tag corresponding to the pipeline stage this builder was obtained from.

Methods inherited from class java.lang.Object

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

Method Detail

tag0

@Nonnull
public Tag<T0> tag0()

Returns the tag corresponding to the pipeline stage this builder was obtained from. Use this tag to refer to this stage when building the AggregateOperation that you'll pass to build(aggrOp).

add

@Nonnull
public <T> Tag<T> add(@Nonnull
                               StreamStageWithKey<T,K> stage)

Adds another stage that will contribute its data to the windowed group-and-aggregate stage being constructed. Returns the tag you'll use to refer to this stage when building the AggregateOperation that you'll pass to build().

build

@Nonnull
public <R> StreamStage<KeyedWindowResult<K,R>> build(@Nonnull
                                                              AggregateOperation<?,? extends R> aggrOp)

Creates and returns a pipeline stage that performs a windowed cogroup-and-aggregate of the pipeline stages registered with this builder object. The tags you register with the aggregate operation must match the tags you registered with this builder.

Type Parameters:

R - the type of the aggregation result

Parameters:

aggrOp - the aggregate operation to perform

Returns:

a new stage representing the co-aggregation

See Also:

AggregateOperations