org.apache.flink.runtime.io.network.api.writer.RoundRobinChannelSelector 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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* See the License for the specific language governing permissions and
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*/
package org.apache.flink.runtime.io.network.api.writer;
import org.apache.flink.core.io.IOReadableWritable;
/**
* This is the default implementation of the {@link ChannelSelector} interface. It represents a
* simple round-robin strategy, i.e. regardless of the record every attached exactly one output
* channel is selected at a time.
*
* @param the type of record which is sent through the attached output gate
*/
public class RoundRobinChannelSelector implements ChannelSelector {
/** Stores the index of the channel to send the next record to. */
private int nextChannelToSendTo = -1;
private int numberOfChannels;
@Override
public void setup(int numberOfChannels) {
this.numberOfChannels = numberOfChannels;
}
@Override
public int selectChannel(final T record) {
nextChannelToSendTo = (nextChannelToSendTo + 1) % numberOfChannels;
return nextChannelToSendTo;
}
@Override
public boolean isBroadcast() {
return false;
}
}