| /** |
| * 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.sqoop.mapreduce; |
| |
| import java.io.*; |
| import java.lang.reflect.*; |
| |
| import org.apache.hadoop.fs.FileSystem; |
| |
| import org.apache.hadoop.mapreduce.*; |
| import org.apache.hadoop.conf.Configuration; |
| |
| /** |
| * This file was ported from Hadoop 2.0.2-alpha |
| */ |
| // CHECKSTYLE:OFF |
| |
| /** |
| * A generic RecordReader that can hand out different recordReaders |
| * for each chunk in a {@link CombineFileSplit}. |
| * A CombineFileSplit can combine data chunks from multiple files. |
| * This class allows using different RecordReaders for processing |
| * these data chunks from different files. |
| * @see CombineFileSplit |
| */ |
| public class CombineFileRecordReader<K, V> extends RecordReader<K, V> { |
| |
| static final Class [] constructorSignature = new Class [] |
| {CombineFileSplit.class, |
| TaskAttemptContext.class, |
| Integer.class}; |
| |
| protected CombineFileSplit split; |
| protected Class<? extends RecordReader<K,V>> rrClass; |
| protected Constructor<? extends RecordReader<K,V>> rrConstructor; |
| protected FileSystem fs; |
| protected TaskAttemptContext context; |
| |
| protected int idx; |
| protected long progress; |
| protected RecordReader<K, V> curReader; |
| |
| public void initialize(InputSplit split, |
| TaskAttemptContext context) throws IOException, InterruptedException { |
| this.split = (CombineFileSplit)split; |
| this.context = context; |
| if (null != this.curReader) { |
| this.curReader.initialize(split, context); |
| } |
| } |
| |
| public boolean nextKeyValue() throws IOException, InterruptedException { |
| |
| while ((curReader == null) || !curReader.nextKeyValue()) { |
| if (!initNextRecordReader()) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| public K getCurrentKey() throws IOException, InterruptedException { |
| return curReader.getCurrentKey(); |
| } |
| |
| public V getCurrentValue() throws IOException, InterruptedException { |
| return curReader.getCurrentValue(); |
| } |
| |
| public void close() throws IOException { |
| if (curReader != null) { |
| curReader.close(); |
| curReader = null; |
| } |
| } |
| |
| /** |
| * return progress based on the amount of data processed so far. |
| */ |
| public float getProgress() throws IOException, InterruptedException { |
| long subprogress = 0; // bytes processed in current split |
| if (null != curReader) { |
| // idx is always one past the current subsplit's true index. |
| subprogress = (long)(curReader.getProgress() * split.getLength(idx - 1)); |
| } |
| return Math.min(1.0f, (progress + subprogress)/(float)(split.getLength())); |
| } |
| |
| /** |
| * A generic RecordReader that can hand out different recordReaders |
| * for each chunk in the CombineFileSplit. |
| */ |
| public CombineFileRecordReader(CombineFileSplit split, |
| TaskAttemptContext context, |
| Class<? extends RecordReader<K,V>> rrClass) |
| throws IOException { |
| this.split = split; |
| this.context = context; |
| this.rrClass = rrClass; |
| this.idx = 0; |
| this.curReader = null; |
| this.progress = 0; |
| |
| try { |
| rrConstructor = rrClass.getDeclaredConstructor(constructorSignature); |
| rrConstructor.setAccessible(true); |
| } catch (Exception e) { |
| throw new RuntimeException(rrClass.getName() + |
| " does not have valid constructor", e); |
| } |
| initNextRecordReader(); |
| } |
| |
| /** |
| * Get the record reader for the next chunk in this CombineFileSplit. |
| */ |
| protected boolean initNextRecordReader() throws IOException { |
| |
| if (curReader != null) { |
| curReader.close(); |
| curReader = null; |
| if (idx > 0) { |
| progress += split.getLength(idx-1); // done processing so far |
| } |
| } |
| |
| // if all chunks have been processed, nothing more to do. |
| if (idx == split.getNumPaths()) { |
| return false; |
| } |
| |
| // get a record reader for the idx-th chunk |
| try { |
| Configuration conf = context.getConfiguration(); |
| // setup some helper config variables. |
| conf.set("map.input.file", split.getPath(idx).toString()); |
| conf.setLong("map.input.start", split.getOffset(idx)); |
| conf.setLong("map.input.length", split.getLength(idx)); |
| |
| curReader = rrConstructor.newInstance(new Object [] |
| {split, context, Integer.valueOf(idx)}); |
| |
| if (idx > 0) { |
| // initialize() for the first RecordReader will be called by MapTask; |
| // we're responsible for initializing subsequent RecordReaders. |
| curReader.initialize(split, context); |
| } |
| } catch (Exception e) { |
| throw new RuntimeException (e); |
| } |
| idx++; |
| return true; |
| } |
| } |
| // CHECKSTYLE:ON |