| /** |
| * 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; |
| |
| import java.io.IOException; |
| |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| |
| import org.apache.hadoop.io.MapFile; |
| import org.apache.hadoop.io.WritableComparable; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.io.SequenceFile.CompressionType; |
| import org.apache.hadoop.io.compress.CompressionCodec; |
| import org.apache.hadoop.io.compress.DefaultCodec; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.util.Progressable; |
| import org.apache.hadoop.util.ReflectionUtils; |
| |
| /** An {@link OutputFormat} that writes {@link MapFile}s. |
| * @deprecated Use |
| * {@link org.apache.hadoop.mapreduce.lib.output.MapFileOutputFormat} instead |
| */ |
| @Deprecated |
| @InterfaceAudience.Public |
| @InterfaceStability.Stable |
| public class MapFileOutputFormat |
| extends FileOutputFormat<WritableComparable, Writable> { |
| |
| public RecordWriter<WritableComparable, Writable> getRecordWriter(FileSystem ignored, JobConf job, |
| String name, Progressable progress) |
| throws IOException { |
| // get the path of the temporary output file |
| Path file = FileOutputFormat.getTaskOutputPath(job, name); |
| |
| FileSystem fs = file.getFileSystem(job); |
| CompressionCodec codec = null; |
| CompressionType compressionType = CompressionType.NONE; |
| if (getCompressOutput(job)) { |
| // find the kind of compression to do |
| compressionType = SequenceFileOutputFormat.getOutputCompressionType(job); |
| |
| // find the right codec |
| Class<? extends CompressionCodec> codecClass = getOutputCompressorClass(job, |
| DefaultCodec.class); |
| codec = ReflectionUtils.newInstance(codecClass, job); |
| } |
| |
| // ignore the progress parameter, since MapFile is local |
| final MapFile.Writer out = |
| new MapFile.Writer(job, fs, file.toString(), |
| job.getOutputKeyClass().asSubclass(WritableComparable.class), |
| job.getOutputValueClass().asSubclass(Writable.class), |
| compressionType, codec, |
| progress); |
| |
| return new RecordWriter<WritableComparable, Writable>() { |
| |
| public void write(WritableComparable key, Writable value) |
| throws IOException { |
| |
| out.append(key, value); |
| } |
| |
| public void close(Reporter reporter) throws IOException { out.close();} |
| }; |
| } |
| |
| /** Open the output generated by this format. */ |
| public static MapFile.Reader[] getReaders(FileSystem ignored, Path dir, |
| Configuration conf) |
| throws IOException { |
| return org.apache.hadoop.mapreduce.lib.output.MapFileOutputFormat. |
| getReaders(dir, conf); |
| } |
| |
| /** Get an entry from output generated by this class. */ |
| public static <K extends WritableComparable, V extends Writable> |
| Writable getEntry(MapFile.Reader[] readers, |
| Partitioner<K, V> partitioner, |
| K key, |
| V value) throws IOException { |
| int part = partitioner.getPartition(key, value, readers.length); |
| return readers[part].get(key, value); |
| } |
| |
| } |
| |