com.hazelcast.jet.pipeline.GroupAggregateBuilder1 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.function.BiFunctionEx;
import com.hazelcast.jet.Util;
import com.hazelcast.jet.aggregate.AggregateOperation;
import com.hazelcast.jet.core.Processor;
import com.hazelcast.jet.datamodel.Tag;
import com.hazelcast.jet.impl.pipeline.GrAggBuilder;
import javax.annotation.Nonnull;
import java.util.Map.Entry;
/**
* Offers a step-by-step API to build a pipeline stage that co-groups and
* aggregates the data from several input stages. To obtain it, call {@link
* BatchStageWithKey#aggregateBuilder()} on one of the stages to co-group
* and refer to that method's Javadoc for further details.
*
* Note: this is not a builder of {@code
* AggregateOperation}. If that's what you are looking for, go {@link
* AggregateOperation#withCreate here}.
*
* @param type of the stream-0 item
* @param type of the grouping key
*
* @since Jet 3.0
*/
public class GroupAggregateBuilder1 {
private final GrAggBuilder grAggBuilder;
GroupAggregateBuilder1(@Nonnull BatchStageWithKey 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 aggregate
* operation to be performed. 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 BatchStageWithKey stage) {
return grAggBuilder.add(stage);
}
/**
* Creates and returns a pipeline stage that performs the co-grouping and
* aggregation of pipeline stages registered with this builder object. The
* tags you register with the aggregate operation must match the tags you
* registered with this builder. It applies the {@code mapToOutputFn} to
* the key and the corresponding result of the aggregate operation to
* obtain the final output of the stage.
*
* @deprecated This is a leftover from an earlier development cycle of the
* Pipeline API. Use {@link #build(AggregateOperation)} instead and add
* a separate mapping stage with {@code mapToOutputFn}.
*
* @param aggrOp the aggregate operation to perform
* @param mapToOutputFn the function to map the output. It must be
* stateless and {@linkplain Processor#isCooperative() cooperative}.
* @param result type of the aggregate operation
* @param output type of the returned stage
* @return a new stage representing the co-group-and-aggregate operation
*/
@Deprecated
@Nonnull
public BatchStage build(
@Nonnull AggregateOperation aggrOp,
@Nonnull BiFunctionEx mapToOutputFn
) {
return grAggBuilder.buildBatch(aggrOp, mapToOutputFn);
}
/**
* Creates and returns a pipeline stage that performs the co-grouping and
* aggregation of pipeline stages registered with this builder object. The
* tags you register with the aggregate operation must match the tags you
* registered with this builder.
*
* @param aggrOp the aggregate operation to perform
* @param output type of the returned stage
* @return a new stage representing the co-group-and-aggregate operation
*/
@Nonnull
public BatchStage> build(
@Nonnull AggregateOperation aggrOp
) {
return grAggBuilder.buildBatch(aggrOp, Util::entry);
}
}