content: /*
   * 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
   *
   *     https://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.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}.
   *
   * <p>
   * Compares AvroKeys output from the map phase for sorting.
   * </p>
   */
  public class AvroKeyComparator<T> extends Configured implements RawComparator<AvroKey<T>> {
    /** 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<T> x, AvroKey<T> y) {
      return mDataModel.compare(x.datum(), y.datum(), mSchema);
    }
  }
  