org.apache.flink.streaming.runtime.translators.SideOutputTransformationTranslator Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* to you 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,
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*/
package org.apache.flink.streaming.runtime.translators;
import org.apache.flink.annotation.Internal;
import org.apache.flink.api.dag.Transformation;
import org.apache.flink.streaming.api.graph.SimpleTransformationTranslator;
import org.apache.flink.streaming.api.graph.StreamGraph;
import org.apache.flink.streaming.api.graph.TransformationTranslator;
import org.apache.flink.streaming.api.transformations.SideOutputTransformation;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import static org.apache.flink.util.Preconditions.checkNotNull;
import static org.apache.flink.util.Preconditions.checkState;
/**
* A {@link TransformationTranslator} for the {@link SideOutputTransformation}.
*
* @param The type of the elements that result from the {@code SideOutputTransformation} being
* translated.
*/
@Internal
public class SideOutputTransformationTranslator
extends SimpleTransformationTranslator> {
@Override
protected Collection translateForBatchInternal(
final SideOutputTransformation transformation, final Context context) {
return translateInternal(transformation, context);
}
@Override
protected Collection translateForStreamingInternal(
final SideOutputTransformation transformation, final Context context) {
return translateInternal(transformation, context);
}
private Collection translateInternal(
final SideOutputTransformation transformation, final Context context) {
checkNotNull(transformation);
checkNotNull(context);
final StreamGraph streamGraph = context.getStreamGraph();
final List> parentTransformations = transformation.getInputs();
checkState(
parentTransformations.size() == 1,
"Expected exactly one input transformation but found "
+ parentTransformations.size());
final List virtualResultIds = new ArrayList<>();
final Transformation parentTransformation = parentTransformations.get(0);
for (int inputId : context.getStreamNodeIds(parentTransformation)) {
final int virtualId = Transformation.getNewNodeId();
streamGraph.addVirtualSideOutputNode(inputId, virtualId, transformation.getOutputTag());
virtualResultIds.add(virtualId);
}
return virtualResultIds;
}
}