com.google.cloud.bigtable.mapreduce.ShuffledSequenceFileInputFormat Maven / Gradle / Ivy
/*
* Copyright 2016 Google LLC
*
* 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.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.cloud.bigtable.mapreduce;
import java.io.IOException;
import java.util.Collections;
import java.util.List;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat;
/**
* An InputFormat randomizes the order of SequenceFile splits. This is needed for the Bigtable
* import job to spread the load across all of the Bigtable tablet servers.
*
* @author igorbernstein2
* @version $Id: $Id
*/
public class ShuffledSequenceFileInputFormat extends SequenceFileInputFormat {
@Override
public List getSplits(JobContext job) throws IOException {
List splits = super.getSplits(job);
Collections.shuffle(splits);
return splits;
}
}