package com.mongodb.hadoop.input;
import com.mongodb.hadoop.io.BSONWritable;
import com.mongodb.hadoop.util.BSONLoader;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;
import org.bson.*;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Copyright (c) 2008 - 2012 10gen, Inc. <http://10gen.com>
* <p/>
* Licensed 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
* <p/>
* http://www.apache.org/licenses/LICENSE-2.0
* <p/>
* 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.
*/
public class BSONFileRecordReader extends RecordReader<NullWritable, BSONWritable> {
private FileSplit fileSplit;
private Configuration conf;
private BSONLoader rdr;
private static final Log log = LogFactory.getLog(BSONFileRecordReader.class);
private Object key;
private BSONWritable value;
@Override
public void initialize(InputSplit inputSplit, TaskAttemptContext context) throws IOException, InterruptedException {
this.fileSplit = (FileSplit) inputSplit;
this.conf = context.getConfiguration();
Path file = fileSplit.getPath();
FileSystem fs = file.getFileSystem(conf);
FSDataInputStream in = null;
in = fs.open(file);
rdr = new BSONLoader(in);
}
@Override
public boolean nextKeyValue() throws IOException, InterruptedException {
if (rdr.hasNext()) {
value = new BSONWritable( rdr.next() );
return true;
} else {
return false;
}
}
@Override
public NullWritable getCurrentKey() throws IOException, InterruptedException {
return NullWritable.get();
}
@Override
public BSONWritable getCurrentValue() throws IOException, InterruptedException {
return value;
}
@Override
public float getProgress() throws IOException, InterruptedException {
return rdr.hasNext() ? 1.0f : 0.0f;
}
@Override
public void close() throws IOException {
// do nothing
}
}