org.apache.flink.streaming.api.transformations.SourceTransformation Maven / Gradle / Ivy
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* distributed with this work for additional information
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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.annotation.Internal;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.streaming.api.operators.ChainingStrategy;
import org.apache.flink.streaming.api.operators.StreamSource;
import java.util.Collection;
import java.util.Collections;
/**
* This represents a Source. This does not actually transform anything since it has no inputs but
* it is the root {@code StreamTransformation} of any topology.
*
* @param The type of the elements that this source produces
*/
@Internal
public class SourceTransformation extends StreamTransformation {
private final StreamSource operator;
/**
* Creates a new {@code SourceTransformation} from the given operator.
*
* @param name The name of the {@code SourceTransformation}, this will be shown in Visualizations and the Log
* @param operator The {@code StreamSource} that is the operator of this Transformation
* @param outputType The type of the elements produced by this {@code SourceTransformation}
* @param parallelism The parallelism of this {@code SourceTransformation}
*/
public SourceTransformation(
String name,
StreamSource operator,
TypeInformation outputType,
int parallelism) {
super(name, outputType, parallelism);
this.operator = operator;
}
/**
* Returns the {@code StreamSource}, the operator of this {@code SourceTransformation}.
*/
public StreamSource getOperator() {
return operator;
}
@Override
public Collection> getTransitivePredecessors() {
return Collections.>singleton(this);
}
@Override
public final void setChainingStrategy(ChainingStrategy strategy) {
operator.setChainingStrategy(strategy);
}
}