/**
* Licensed to Odiago, Inc. under one or more contributor license
* agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership. Odiago, Inc.
* 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.mapreduce;
import java.io.IOException;
import org.apache.avro.hadoop.io.AvroDatumConverter;
import org.apache.avro.hadoop.io.AvroDatumConverterFactory;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
/**
* FileOutputFormat for writing Avro container files of key/value pairs.
*
* <p>Since Avro container files can only contain records (not key/value pairs), this
* output format puts the key and value into an Avro generic record with two fields, named
* 'key' and 'value'.</p>
*
* <p>The keys and values given to this output format may be Avro objects wrapped in
* <code>AvroKey</code> or <code>AvroValue</code> objects. The basic Writable types are
* also supported (e.g., IntWritable, Text); they will be converted to their corresponding
* Avro types.</p>
*
* @param <K> The type of key. If an Avro type, it must be wrapped in an <code>AvroKey</code>.
* @param <V> The type of value. If an Avro type, it must be wrapped in an <code>AvroValue</code>.
*/
public class AvroKeyValueOutputFormat<K, V> extends AvroOutputFormatBase<K, V> {
/** {@inheritDoc} */
@Override
@SuppressWarnings("unchecked")
public RecordWriter<K, V> getRecordWriter(TaskAttemptContext context) throws IOException {
AvroDatumConverterFactory converterFactory = new AvroDatumConverterFactory(
context.getConfiguration());
AvroDatumConverter<K, ?> keyConverter = converterFactory.create(
(Class<K>) context.getOutputKeyClass());
AvroDatumConverter<V, ?> valueConverter = converterFactory.create(
(Class<V>) context.getOutputValueClass());
return new AvroKeyValueRecordWriter<K, V>(keyConverter, valueConverter,
getCompressionCodec(context), getAvroFileOutputStream(context));
}
}