/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* 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,
* 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 org.apache.flink.runtime.io.network.api.writer;
import org.apache.flink.core.io.IOReadableWritable;
/**
* The {@link ChannelSelector} determines to which logical channels a record
* should be written to.
*
* @param <T> the type of record which is sent through the attached output gate
*/
public interface ChannelSelector<T extends IOReadableWritable> {
/**
* Returns the logical channel indexes, to which the given record should be
* written.
*
* @param record the record to the determine the output channels for
* @param numChannels the total number of output channels which are attached to respective output gate
* @return a (possibly empty) array of integer numbers which indicate the indices of the output channels through
* which the record shall be forwarded
*/
int[] selectChannels(T record, int numChannels);
}