/**
* 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.avro.mapred.tether;
import java.io.IOException;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.avro.Schema;
import org.apache.avro.file.DataFileReader;
import org.apache.avro.generic.GenericDatumReader;
import org.apache.avro.mapred.AvroJob;
import org.apache.avro.mapred.FsInput;
class TetherRecordReader
implements RecordReader<TetherData, NullWritable> {
private FsInput in;
private DataFileReader reader;
private long start;
private long end;
public TetherRecordReader(JobConf job, FileSplit split)
throws IOException {
this.in = new FsInput(split.getPath(), job);
this.reader =
new DataFileReader<Object>(in, new GenericDatumReader<Object>());
reader.sync(split.getStart()); // sync to start
this.start = in.tell();
this.end = split.getStart() + split.getLength();
job.set(AvroJob.INPUT_SCHEMA, reader.getSchema().toString());
}
public Schema getSchema() { return reader.getSchema(); }
public TetherData createKey() { return new TetherData(); }
public NullWritable createValue() { return NullWritable.get(); }
public boolean next(TetherData data, NullWritable ignore)
throws IOException {
if (!reader.hasNext() || reader.pastSync(end))
return false;
data.buffer(reader.nextBlock());
data.count((int)reader.getBlockCount());
return true;
}
public float getProgress() throws IOException {
if (end == start) {
return 0.0f;
} else {
return Math.min(1.0f, (in.tell() - start) / (float)(end - start));
}
}
public long getPos() throws IOException {
return in.tell();
}
public void close() throws IOException { reader.close(); }
}