| /** |
| * 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.hadoop.mapred.nativetask.handlers; |
| |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| |
| import org.apache.commons.io.IOUtils; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.io.DataInputBuffer; |
| import org.apache.hadoop.mapred.RawKeyValueIterator; |
| import org.apache.hadoop.mapred.nativetask.Constants; |
| import org.apache.hadoop.mapred.nativetask.DataReceiver; |
| import org.apache.hadoop.mapred.nativetask.NativeDataSource; |
| import org.apache.hadoop.mapred.nativetask.buffer.BufferType; |
| import org.apache.hadoop.mapred.nativetask.buffer.ByteBufferDataReader; |
| import org.apache.hadoop.mapred.nativetask.buffer.InputBuffer; |
| import org.apache.hadoop.util.Progress; |
| |
| /** |
| * actively signal a {@link BufferPullee} to load data into buffer and receive |
| */ |
| @InterfaceAudience.Private |
| public class BufferPuller implements RawKeyValueIterator, DataReceiver { |
| |
| private static Log LOG = LogFactory.getLog(BufferPuller.class); |
| |
| public final static int KV_HEADER_LENGTH = Constants.SIZEOF_KV_LENGTH; |
| |
| byte[] keyBytes = new byte[0]; |
| byte[] valueBytes = new byte[0]; |
| |
| private InputBuffer inputBuffer; |
| private InputBuffer asideBuffer; |
| |
| int remain = 0; |
| |
| private ByteBufferDataReader nativeReader; |
| |
| DataInputBuffer keyBuffer = new DataInputBuffer(); |
| DataInputBuffer valueBuffer = new DataInputBuffer(); |
| |
| private boolean noMoreData = false; |
| |
| private NativeDataSource input; |
| private boolean closed = false; |
| |
| public BufferPuller(NativeDataSource handler) throws IOException { |
| this.input = handler; |
| this.inputBuffer = handler.getInputBuffer(); |
| nativeReader = new ByteBufferDataReader(null); |
| this.asideBuffer = new InputBuffer(BufferType.HEAP_BUFFER, inputBuffer.capacity()); |
| } |
| |
| @Override |
| public DataInputBuffer getKey() throws IOException { |
| return keyBuffer; |
| } |
| |
| @Override |
| public DataInputBuffer getValue() throws IOException { |
| return valueBuffer; |
| } |
| |
| public void reset() { |
| noMoreData = false; |
| } |
| |
| @Override |
| public boolean next() throws IOException { |
| if (closed) { |
| return false; |
| } |
| |
| if (noMoreData) { |
| return false; |
| } |
| final int asideRemain = asideBuffer.remaining(); |
| final int inputRemain = inputBuffer.remaining(); |
| |
| if (asideRemain == 0 && inputRemain == 0) { |
| input.loadData(); |
| } |
| |
| if (asideBuffer.remaining() > 0) { |
| return nextKeyValue(asideBuffer); |
| } else if (inputBuffer.remaining() > 0) { |
| return nextKeyValue(inputBuffer); |
| } else { |
| noMoreData = true; |
| return false; |
| } |
| } |
| |
| private boolean nextKeyValue(InputBuffer buffer) throws IOException { |
| if (closed) { |
| return false; |
| } |
| |
| nativeReader.reset(buffer); |
| |
| final int keyLength = nativeReader.readInt(); |
| if (keyBytes.length < keyLength) { |
| keyBytes = new byte[keyLength]; |
| } |
| |
| final int valueLength = nativeReader.readInt(); |
| if (valueBytes.length < valueLength) { |
| valueBytes = new byte[valueLength]; |
| } |
| |
| IOUtils.readFully(nativeReader, keyBytes, 0, keyLength); |
| IOUtils.readFully(nativeReader, valueBytes, 0, valueLength); |
| |
| keyBuffer.reset(keyBytes, keyLength); |
| valueBuffer.reset(valueBytes, valueLength); |
| |
| return true; |
| } |
| |
| @Override |
| public boolean receiveData() throws IOException { |
| if (closed) { |
| return false; |
| } |
| |
| final ByteBuffer input = inputBuffer.getByteBuffer(); |
| |
| if (null != asideBuffer && asideBuffer.length() > 0) { |
| if (asideBuffer.remaining() > 0) { |
| final byte[] output = asideBuffer.getByteBuffer().array(); |
| final int write = Math.min(asideBuffer.remaining(), input.remaining()); |
| input.get(output, asideBuffer.position(), write); |
| asideBuffer.position(asideBuffer.position() + write); |
| } |
| |
| if (asideBuffer.remaining() == 0) { |
| asideBuffer.position(0); |
| } |
| } |
| |
| if (input.remaining() == 0) { |
| return true; |
| } |
| |
| if (input.remaining() < KV_HEADER_LENGTH) { |
| throw new IOException("incomplete data, input length is: " + input.remaining()); |
| } |
| final int position = input.position(); |
| final int keyLength = input.getInt(); |
| final int valueLength = input.getInt(); |
| input.position(position); |
| final int kvLength = keyLength + valueLength + KV_HEADER_LENGTH; |
| final int remaining = input.remaining(); |
| |
| if (kvLength > remaining) { |
| if (null == asideBuffer || asideBuffer.capacity() < kvLength) { |
| asideBuffer = new InputBuffer(BufferType.HEAP_BUFFER, kvLength); |
| } |
| asideBuffer.rewind(0, kvLength); |
| |
| input.get(asideBuffer.array(), 0, remaining); |
| asideBuffer.position(remaining); |
| } |
| return true; |
| } |
| |
| @Override |
| public Progress getProgress() { |
| return null; |
| } |
| |
| /** |
| * Closes the iterator so that the underlying streams can be closed. |
| */ |
| @Override |
| public void close() throws IOException { |
| if (closed) { |
| return; |
| } |
| if (null != nativeReader) { |
| nativeReader.close(); |
| } |
| closed = true; |
| } |
| } |