org.apache.avro.mapreduce.CombineAvroKeyValueFileInputFormat Maven / Gradle / Ivy
/**
* 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.mapred.AvroKey;
import org.apache.avro.mapred.AvroValue;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.CombineFileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReader;
import org.apache.hadoop.mapreduce.lib.input.CombineFileRecordReaderWrapper;
import org.apache.hadoop.mapreduce.lib.input.CombineFileSplit;
/**
* A combine avro keyvalue file input format that can combine small avro files
* into mappers.
*
* @param The type of the Avro key to read.
* @param The type of the Avro value to read.
*/
public class CombineAvroKeyValueFileInputFormat extends CombineFileInputFormat, AvroValue> {
@Override
public RecordReader, AvroValue> createRecordReader(InputSplit inputSplit,
TaskAttemptContext taskAttemptContext) throws IOException {
return new CombineFileRecordReader((CombineFileSplit) inputSplit, taskAttemptContext,
CombineAvroKeyValueFileInputFormat.AvroKeyValueFileRecordReaderWrapper.class);
}
/**
* A record reader that may be passed to CombineFileRecordReader so
* that it can be used in a CombineFileInputFormat-equivalent for
* AvroKeyValueInputFormat.
*
* @see CombineFileRecordReader
* @see CombineFileInputFormat
* @see AvroKeyValueInputFormat
*/
private static class AvroKeyValueFileRecordReaderWrapper
extends CombineFileRecordReaderWrapper, AvroValue> {
// this constructor signature is required by CombineFileRecordReader
public AvroKeyValueFileRecordReaderWrapper(CombineFileSplit split, TaskAttemptContext context, Integer idx)
throws IOException, InterruptedException {
super(new AvroKeyValueInputFormat<>(), split, context, idx);
}
}
}