org.apache.flink.streaming.api.transformations.SideOutputTransformation Maven / Gradle / Ivy
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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.api.transformations;
import org.apache.flink.api.dag.Transformation;
import org.apache.flink.util.OutputTag;
import org.apache.flink.shaded.guava30.com.google.common.collect.Lists;
import java.util.Collections;
import java.util.List;
import static java.util.Objects.requireNonNull;
/**
* This transformation represents a selection of a side output of an upstream operation with a given
* {@link OutputTag}.
*
* This does not create a physical operation, it only affects how upstream operations are
* connected to downstream operations.
*
* @param The type of the elements that result from this {@code SideOutputTransformation}
*/
public class SideOutputTransformation extends Transformation {
private final Transformation input;
private final OutputTag tag;
public SideOutputTransformation(Transformation input, final OutputTag tag) {
super("SideOutput", tag.getTypeInfo(), requireNonNull(input).getParallelism());
this.input = input;
this.tag = requireNonNull(tag);
}
public OutputTag getOutputTag() {
return tag;
}
@Override
public List> getTransitivePredecessors() {
List> result = Lists.newArrayList();
result.add(this);
result.addAll(input.getTransitivePredecessors());
return result;
}
@Override
public List> getInputs() {
return Collections.singletonList(input);
}
}