org.apache.flink.runtime.io.disk.iomanager.SynchronousBufferFileReader Maven / Gradle / Ivy
/*
* 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.iomanager;
import org.apache.flink.runtime.io.network.buffer.Buffer;
import java.io.IOException;
/**
* A synchronous {@link BufferFileReader} implementation.
*
* This currently bypasses the I/O manager as it is the only synchronous implementation, which
* is currently in use.
*
* TODO Refactor I/O manager setup and refactor this into it
*/
public class SynchronousBufferFileReader extends SynchronousFileIOChannel implements BufferFileReader {
private final BufferFileChannelReader reader;
private boolean hasReachedEndOfFile;
public SynchronousBufferFileReader(ID channelID, boolean writeEnabled) throws IOException {
super(channelID, writeEnabled);
this.reader = new BufferFileChannelReader(fileChannel);
}
@Override
public void readInto(Buffer buffer) throws IOException {
if (fileChannel.size() - fileChannel.position() > 0) {
hasReachedEndOfFile = reader.readBufferFromFileChannel(buffer);
}
else {
buffer.recycleBuffer();
}
}
@Override
public void seekToPosition(long position) throws IOException {
fileChannel.position(position);
}
@Override
public boolean hasReachedEndOfFile() {
return hasReachedEndOfFile;
}
}