| /* |
| * 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 |
| * |
| * 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 org.apache.giraph.partition; |
| |
| import org.apache.giraph.conf.GiraphConstants; |
| import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration; |
| import org.apache.hadoop.io.IntWritable; |
| import org.apache.hadoop.io.Writable; |
| |
| /** |
| * Factory for simple range-based partitioners based on integer vertex ids. |
| * Workers are assigned equal-sized ranges of partitions, |
| * and partitions are assigned equal-sized ranges of vertices. |
| * |
| * @param <V> Vertex value type |
| * @param <E> Edge value type |
| */ |
| public class SimpleIntRangePartitionerFactory<V extends Writable, |
| E extends Writable> extends GraphPartitionerFactory<IntWritable, V, E> { |
| |
| /** Vertex key space size. */ |
| private int keySpaceSize; |
| |
| @Override |
| public int getPartition(IntWritable id, int partitionCount, |
| int workerCount) { |
| return getPartition(id, partitionCount); |
| } |
| |
| /** |
| * Calculates in which partition current vertex belongs to, |
| * from interval [0, partitionCount). |
| * |
| * @param id Vertex id |
| * @param partitionCount Number of partitions |
| * @return partition |
| */ |
| protected int getPartition(IntWritable id, int partitionCount) { |
| return getPartitionInRange(id.get(), keySpaceSize, partitionCount); |
| } |
| |
| @Override |
| public int getWorker(int partition, int partitionCount, int workerCount) { |
| return getPartitionInRange(partition, partitionCount, workerCount); |
| } |
| |
| @Override |
| public void setConf(ImmutableClassesGiraphConfiguration conf) { |
| super.setConf(conf); |
| keySpaceSize = |
| conf.getInt(GiraphConstants.PARTITION_VERTEX_KEY_SPACE_SIZE, -1); |
| if (keySpaceSize == -1) { |
| throw new IllegalStateException("Need to specify " + |
| GiraphConstants.PARTITION_VERTEX_KEY_SPACE_SIZE + |
| " when using SimpleIntRangePartitionerFactory"); |
| } |
| } |
| } |