PrestoSparkPartitioner.java
/*
* 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.facebook.presto.spark.classloader_interface;
import org.apache.spark.Partitioner;
import static java.lang.String.format;
import static java.util.Objects.requireNonNull;
public class PrestoSparkPartitioner
extends Partitioner
{
private final int numPartitions;
public PrestoSparkPartitioner(int numPartitions)
{
this.numPartitions = numPartitions;
}
@Override
public int numPartitions()
{
return numPartitions;
}
@Override
public int getPartition(Object key)
{
requireNonNull(key, "key is null");
MutablePartitionId mutablePartitionId = (MutablePartitionId) key;
int partition = mutablePartitionId.getPartition();
if (!(partition >= 0 && partition < numPartitions)) {
throw new IllegalArgumentException(format("Unexpected partition: %s. Total number of partitions: %s.", partition, numPartitions));
}
return partition;
}
}