| /** |
| * 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.mapreduce.lib.input; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| import org.apache.hadoop.io.BytesWritable; |
| import org.apache.hadoop.io.DataOutputBuffer; |
| import org.apache.hadoop.io.SequenceFile; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| import org.apache.hadoop.mapreduce.RecordReader; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| |
| /** |
| * InputFormat reading keys, values from SequenceFiles in binary (raw) |
| * format. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Stable |
| public class SequenceFileAsBinaryInputFormat |
| extends SequenceFileInputFormat<BytesWritable,BytesWritable> { |
| |
| public SequenceFileAsBinaryInputFormat() { |
| super(); |
| } |
| |
| public RecordReader<BytesWritable,BytesWritable> createRecordReader( |
| InputSplit split, TaskAttemptContext context) |
| throws IOException { |
| return new SequenceFileAsBinaryRecordReader(); |
| } |
| |
| /** |
| * Read records from a SequenceFile as binary (raw) bytes. |
| */ |
| public static class SequenceFileAsBinaryRecordReader |
| extends RecordReader<BytesWritable,BytesWritable> { |
| private SequenceFile.Reader in; |
| private long start; |
| private long end; |
| private boolean done = false; |
| private DataOutputBuffer buffer = new DataOutputBuffer(); |
| private SequenceFile.ValueBytes vbytes; |
| private BytesWritable key = null; |
| private BytesWritable value = null; |
| |
| public void initialize(InputSplit split, TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| Path path = ((FileSplit)split).getPath(); |
| Configuration conf = context.getConfiguration(); |
| FileSystem fs = path.getFileSystem(conf); |
| this.in = new SequenceFile.Reader(fs, path, conf); |
| this.end = ((FileSplit)split).getStart() + split.getLength(); |
| if (((FileSplit)split).getStart() > in.getPosition()) { |
| in.sync(((FileSplit)split).getStart()); // sync to start |
| } |
| this.start = in.getPosition(); |
| vbytes = in.createValueBytes(); |
| done = start >= end; |
| } |
| |
| @Override |
| public BytesWritable getCurrentKey() |
| throws IOException, InterruptedException { |
| return key; |
| } |
| |
| @Override |
| public BytesWritable getCurrentValue() |
| throws IOException, InterruptedException { |
| return value; |
| } |
| |
| /** |
| * Retrieve the name of the key class for this SequenceFile. |
| * @see org.apache.hadoop.io.SequenceFile.Reader#getKeyClassName |
| */ |
| public String getKeyClassName() { |
| return in.getKeyClassName(); |
| } |
| |
| /** |
| * Retrieve the name of the value class for this SequenceFile. |
| * @see org.apache.hadoop.io.SequenceFile.Reader#getValueClassName |
| */ |
| public String getValueClassName() { |
| return in.getValueClassName(); |
| } |
| |
| /** |
| * Read raw bytes from a SequenceFile. |
| */ |
| public synchronized boolean nextKeyValue() |
| throws IOException, InterruptedException { |
| if (done) { |
| return false; |
| } |
| long pos = in.getPosition(); |
| boolean eof = -1 == in.nextRawKey(buffer); |
| if (!eof) { |
| if (key == null) { |
| key = new BytesWritable(); |
| } |
| if (value == null) { |
| value = new BytesWritable(); |
| } |
| key.set(buffer.getData(), 0, buffer.getLength()); |
| buffer.reset(); |
| in.nextRawValue(vbytes); |
| vbytes.writeUncompressedBytes(buffer); |
| value.set(buffer.getData(), 0, buffer.getLength()); |
| buffer.reset(); |
| } |
| return !(done = (eof || (pos >= end && in.syncSeen()))); |
| } |
| |
| public void close() throws IOException { |
| in.close(); |
| } |
| |
| /** |
| * Return the progress within the input split |
| * @return 0.0 to 1.0 of the input byte range |
| */ |
| public float getProgress() throws IOException, InterruptedException { |
| if (end == start) { |
| return 0.0f; |
| } else { |
| return Math.min(1.0f, (float)((in.getPosition() - start) / |
| (double)(end - start))); |
| } |
| } |
| } |
| } |