Java tutorial
/* (c) 2014 LinkedIn Corp. All rights reserved. * * Licensed 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. */ package com.linkedin.cubert.io.avro; import java.io.IOException; import java.util.List; import org.apache.avro.Schema; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.io.Writable; import org.apache.hadoop.mapreduce.InputSplit; import org.apache.hadoop.mapreduce.JobContext; import org.apache.hadoop.mapreduce.RecordReader; import org.apache.hadoop.mapreduce.TaskAttemptContext; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import com.linkedin.cubert.pig.piggybank.storage.avro.PigAvroInputFormat; public class PigAvroInputFormatAdaptor extends FileInputFormat<NullWritable, Writable> { private PigAvroInputFormat delegate; @Override protected boolean isSplitable(JobContext context, Path filename) { Configuration conf = context.getConfiguration(); return !conf.getBoolean("cubert.avro.input.unsplittable", false); } @Override public List<InputSplit> getSplits(JobContext job) throws IOException { return getDelegate(job.getConfiguration()).getSplits(job); } @Override public RecordReader<NullWritable, Writable> createRecordReader(InputSplit split, TaskAttemptContext context) throws IOException, InterruptedException { return getDelegate(context.getConfiguration()).createRecordReader(split, context); } private PigAvroInputFormat getDelegate(Configuration conf) { if (delegate == null) { String schemaStr = conf.get("cubert.avro.input.schema"); Schema schema = new Schema.Parser().parse(schemaStr); delegate = new PigAvroInputFormat(schema, false, null, false); } return delegate; } }