org.apache.avro.hadoop.io.AvroKeyComparator Maven / Gradle / Ivy
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* 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
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
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*/
package org.apache.avro.hadoop.io;
import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.io.BinaryData;
import org.apache.avro.mapred.AvroKey;
import org.apache.avro.mapreduce.AvroJob;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.io.RawComparator;
/**
* The {@link org.apache.hadoop.io.RawComparator} used by jobs configured with
* {@link org.apache.avro.mapreduce.AvroJob}.
*
*
* Compares AvroKeys output from the map phase for sorting.
*
*/
public class AvroKeyComparator extends Configured implements RawComparator> {
/** The schema of the Avro data in the key to compare. */
private Schema mSchema;
private GenericData mDataModel;
/** {@inheritDoc} */
@Override
public void setConf(Configuration conf) {
super.setConf(conf);
if (null != conf) {
// The MapReduce framework will be using this comparator to sort AvroKey objects
// output from the map phase, so use the schema defined for the map output key
// and the data model non-raw compare() implementation.
mSchema = AvroJob.getMapOutputKeySchema(conf);
mDataModel = AvroSerialization.createDataModel(conf);
}
}
/** {@inheritDoc} */
@Override
public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
return BinaryData.compare(b1, s1, b2, s2, mSchema);
}
/** {@inheritDoc} */
@Override
public int compare(AvroKey x, AvroKey y) {
return mDataModel.compare(x.datum(), y.datum(), mSchema);
}
}