| /* |
| * 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.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.FileInputFormat; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * A MapReduce InputFormat that reads from Avro container files of key/value |
| * generic records. |
| * |
| * <p> |
| * Avro container files that container generic records with the two fields 'key' |
| * and 'value' are expected. The contents of the 'key' field will be used as the |
| * job input key, and the contents of the 'value' field will be used as the job |
| * output value. |
| * </p> |
| * |
| * @param <K> The type of the Avro key to read. |
| * @param <V> The type of the Avro value to read. |
| */ |
| public class AvroKeyValueInputFormat<K, V> extends FileInputFormat<AvroKey<K>, AvroValue<V>> { |
| private static final Logger LOG = LoggerFactory.getLogger(AvroKeyValueInputFormat.class); |
| |
| /** {@inheritDoc} */ |
| @Override |
| public RecordReader<AvroKey<K>, AvroValue<V>> createRecordReader(InputSplit split, TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| Schema keyReaderSchema = AvroJob.getInputKeySchema(context.getConfiguration()); |
| if (null == keyReaderSchema) { |
| LOG.warn("Key reader schema was not set. Use AvroJob.setInputKeySchema() if desired."); |
| LOG.info("Using a key reader schema equal to the writer schema."); |
| } |
| Schema valueReaderSchema = AvroJob.getInputValueSchema(context.getConfiguration()); |
| if (null == valueReaderSchema) { |
| LOG.warn("Value reader schema was not set. Use AvroJob.setInputValueSchema() if desired."); |
| LOG.info("Using a value reader schema equal to the writer schema."); |
| } |
| return new AvroKeyValueRecordReader<>(keyReaderSchema, valueReaderSchema); |
| } |
| } |