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.mapreduce;
  
  import java.io.IOException;
  
  import org.apache.avro.Schema;
  import org.apache.avro.mapred.AvroKey;
  import org.apache.hadoop.io.NullWritable;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Reads records from an input split representing a chunk of an Avro container
   * file.
   *
   * @param <T> The (java) type of data in Avro container file.
   */
  public class AvroKeyRecordReader<T> extends AvroRecordReaderBase<AvroKey<T>, NullWritable, T> {
    private static final Logger LOG = LoggerFactory.getLogger(AvroKeyRecordReader.class);
  
    /** A reusable object to hold records of the Avro container file. */
    private final AvroKey<T> mCurrentRecord;
  
    /**
     * Constructor.
     *
     * @param readerSchema The reader schema to use for the records in the Avro
     *                     container file.
     */
    public AvroKeyRecordReader(Schema readerSchema) {
      super(readerSchema);
      mCurrentRecord = new AvroKey<>(null);
    }
  
    /** {@inheritDoc} */
    @Override
    public boolean nextKeyValue() throws IOException, InterruptedException {
      boolean hasNext = super.nextKeyValue();
      mCurrentRecord.datum(getCurrentRecord());
      return hasNext;
    }
  
    /** {@inheritDoc} */
    @Override
    public AvroKey<T> getCurrentKey() throws IOException, InterruptedException {
      return mCurrentRecord;
    }
  
    /** {@inheritDoc} */
    @Override
    public NullWritable getCurrentValue() throws IOException, InterruptedException {
      return NullWritable.get();
    }
  }
  