com.hazelcast.jet.pipeline.WindowGroupAggregateBuilder1 Maven / Gradle / Ivy
/*
* Copyright (c) 2008-2024, Hazelcast, Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hazelcast.jet.pipeline;
import com.hazelcast.jet.aggregate.AggregateOperation;
import com.hazelcast.jet.datamodel.KeyedWindowResult;
import com.hazelcast.jet.datamodel.Tag;
import com.hazelcast.jet.impl.pipeline.GrAggBuilder;
import javax.annotation.Nonnull;
/**
* 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 {@link 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 {@code
* stage.aggregateN(...)} calls because they offer more static type safety.
*
* Note: this is not a builder of {@code
* AggregateOperation}. If that's what you are looking for, go {@link
* AggregateOperation#withCreate here}.
*
* @param the type of the stream-0 item
* @param type of the key
*
* @since Jet 3.0
*/
public class WindowGroupAggregateBuilder1 {
private final GrAggBuilder grAggBuilder;
WindowGroupAggregateBuilder1(@Nonnull StageWithKeyAndWindow s) {
grAggBuilder = new GrAggBuilder<>(s);
}
/**
* Returns the tag corresponding to the pipeline stage this builder
* was obtained from. Use this tag to refer to this stage when building
* the {@code AggregateOperation} that you'll pass to {@link #build
* build(aggrOp)}.
*/
@Nonnull
public Tag tag0() {
return Tag.tag0();
}
/**
* 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 {@code AggregateOperation} that
* you'll pass to {@link #build build()}.
*/
@Nonnull
public Tag add(@Nonnull StreamStageWithKey stage) {
return grAggBuilder.add(stage);
}
/**
* 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.
*
* @see com.hazelcast.jet.aggregate.AggregateOperations AggregateOperations
* @param aggrOp the aggregate operation to perform
* @param the type of the aggregation result
* @return a new stage representing the co-aggregation
*/
@Nonnull
public StreamStage> build(@Nonnull AggregateOperation aggrOp) {
return grAggBuilder.buildStream(aggrOp);
}
}