/*
* 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.disk;
import java.io.EOFException;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.LinkedBlockingQueue;
import org.apache.flink.api.common.typeutils.TypeSerializer;
import org.apache.flink.core.memory.MemorySegment;
import org.apache.flink.runtime.io.disk.iomanager.BlockChannelReader;
import org.apache.flink.runtime.io.disk.iomanager.Channel;
import org.apache.flink.runtime.io.disk.iomanager.ChannelReaderInputView;
import org.apache.flink.runtime.io.disk.iomanager.IOManager;
import org.apache.flink.util.MutableObjectIterator;
/**
* A simple iterator over the input read though an I/O channel.
*
*/
public class ChannelReaderInputViewIterator<E> implements MutableObjectIterator<E>
{
private final ChannelReaderInputView inView;
private final TypeSerializer<E> accessors;
private final List<MemorySegment> freeMemTarget;
public ChannelReaderInputViewIterator(IOManager ioAccess, Channel.ID channel, List<MemorySegment> segments,
List<MemorySegment> freeMemTarget, TypeSerializer<E> accessors, int numBlocks)
throws IOException
{
this(ioAccess, channel, new LinkedBlockingQueue<MemorySegment>(), segments, freeMemTarget, accessors, numBlocks);
}
public ChannelReaderInputViewIterator(IOManager ioAccess, Channel.ID channel, LinkedBlockingQueue<MemorySegment> returnQueue,
List<MemorySegment> segments, List<MemorySegment> freeMemTarget, TypeSerializer<E> accessors, int numBlocks)
throws IOException
{
this(ioAccess.createBlockChannelReader(channel, returnQueue), returnQueue,
segments, freeMemTarget, accessors, numBlocks);
}
public ChannelReaderInputViewIterator(BlockChannelReader reader, LinkedBlockingQueue<MemorySegment> returnQueue,
List<MemorySegment> segments, List<MemorySegment> freeMemTarget, TypeSerializer<E> accessors, int numBlocks)
throws IOException
{
this.accessors = accessors;
this.freeMemTarget = freeMemTarget;
this.inView = new ChannelReaderInputView(reader, segments, numBlocks, false);
}
public ChannelReaderInputViewIterator(ChannelReaderInputView inView, List<MemorySegment> freeMemTarget, TypeSerializer<E> accessors)
{
this.inView = inView;
this.freeMemTarget = freeMemTarget;
this.accessors = accessors;
}
@Override
public E next(E reuse) throws IOException
{
try {
return this.accessors.deserialize(reuse, this.inView);
} catch (EOFException eofex) {
final List<MemorySegment> freeMem = this.inView.close();
if (this.freeMemTarget != null) {
this.freeMemTarget.addAll(freeMem);
}
return null;
}
}
}