org.apache.flink.runtime.io.network.partition.hybrid.HsDataView 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
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*/
package org.apache.flink.runtime.io.network.partition.hybrid;
import org.apache.flink.runtime.io.network.buffer.Buffer;
import org.apache.flink.runtime.io.network.buffer.Buffer.DataType;
import org.apache.flink.runtime.io.network.partition.ResultSubpartition.BufferAndBacklog;
import java.util.Collection;
import java.util.Optional;
/**
* A view for {@link HsSubpartitionConsumer} to find out what data exists in memory or disk and
* polling the data.
*/
public interface HsDataView {
/**
* Try to consume next buffer.
*
* Only invoked by consumer thread.
*
* @param nextBufferToConsume next buffer index to consume.
* @param buffersToRecycle buffers to recycle if needed.
* @return If the target buffer does exist, return buffer and next buffer's backlog, otherwise
* return {@link Optional#empty()}.
*/
Optional consumeBuffer(
int nextBufferToConsume, Collection buffersToRecycle) throws Throwable;
/**
* Get dataType of next buffer to consume.
*
* @param nextBufferToConsume next buffer index to consume
* @param buffersToRecycle buffers to recycle if needed.
* @return next buffer's dataType. If not found in memory, return {@link DataType#NONE}.
*/
DataType peekNextToConsumeDataType(
int nextBufferToConsume, Collection buffersToRecycle);
/**
* Get the number of buffers backlog.
*
* @return backlog of this view's corresponding subpartition.
*/
int getBacklog();
/** Release this {@link HsDataView} when related subpartition view is releasing. */
void releaseDataView();
}