org.apache.flink.runtime.io.network.partition.BoundedData Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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* 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.runtime.io.network.partition;
import org.apache.flink.runtime.io.network.buffer.Buffer;
import javax.annotation.Nullable;
import java.io.Closeable;
import java.io.IOException;
import java.nio.file.Path;
/**
* BoundedData is the data store in a single bounded blocking subpartition.
*
* Life cycle
*
* The BoundedData is first created during the "write phase" by writing a sequence of buffers
* through the {@link #writeBuffer(Buffer)} method. The write phase is ended by calling {@link
* #finishWrite()}. After the write phase is finished, the data can be read multiple times through
* readers created via {@link #createReader(ResultSubpartitionView)}. Finally, the BoundedData is
* dropped / deleted by calling {@link #close()}.
*
*
Thread Safety and Concurrency
*
* The implementations generally make no assumptions about thread safety. The only contract is
* that multiple created readers must be able to work independently concurrently.
*/
interface BoundedData extends Closeable {
/**
* Writes this buffer to the bounded data. This call fails if the writing phase was already
* finished via {@link #finishWrite()}.
*/
void writeBuffer(Buffer buffer) throws IOException;
/**
* Finishes the current region and prevents further writes. After calling this method, further
* calls to {@link #writeBuffer(Buffer)} will fail.
*/
void finishWrite() throws IOException;
/**
* Gets a reader for the bounded data. Multiple readers may be created. This call only succeeds
* once the write phase was finished via {@link #finishWrite()}.
*/
BoundedData.Reader createReader(ResultSubpartitionView subpartitionView) throws IOException;
/**
* Gets a reader for the bounded data. Multiple readers may be created. This call only succeeds
* once the write phase was finished via {@link #finishWrite()}.
*/
default BoundedData.Reader createReader() throws IOException {
return createReader(new NoOpResultSubpartitionView());
}
/**
* Gets the number of bytes of all written data (including the metadata in the buffer headers).
*/
long getSize();
/** The file path for the persisted {@link BoundedBlockingSubpartition}. */
Path getFilePath();
// ------------------------------------------------------------------------
/** A reader to the bounded data. */
interface Reader extends Closeable {
@Nullable
Buffer nextBuffer() throws IOException;
}
}