io.cdap.cdap.internal.app.runtime.batch.PartitionerWrapper Maven / Gradle / Ivy
/*
* Copyright © 2016 Cask Data, Inc.
*
* 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 io.cdap.cdap.internal.app.runtime.batch;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.MRJobConfig;
import org.apache.hadoop.mapreduce.Partitioner;
/**
* Wraps user-defined implementation of {@link Partitioner} class which allows to perform extra configuration.
*/
public class PartitionerWrapper extends Partitioner implements Configurable {
private static final String ATTR_CLASS = "c.partitioner.class";
private Partitioner delegate;
private Configuration conf;
/**
* Wraps the partitioner defined in the job with this {@link PartitionerWrapper} if it is defined.
* @param job The MapReduce job
*/
public static void wrap(Job job) {
if (WrapperUtil.setIfDefined(job, MRJobConfig.PARTITIONER_CLASS_ATTR, ATTR_CLASS)) {
job.setPartitionerClass(PartitionerWrapper.class);
}
}
@Override
public int getPartition(Object o, Object o2, int numPartitions) {
return delegate.getPartition(o, o2, numPartitions);
}
@Override
public void setConf(Configuration conf) {
this.conf = conf;
this.delegate = WrapperUtil.createDelegate(conf, ATTR_CLASS);
}
@Override
public Configuration getConf() {
return conf;
}
}