org.acacia.csr.java.VertexPartitioner.java Source code

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Here is the source code for org.acacia.csr.java.VertexPartitioner.java

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/**
Copyright 2015 Acacia Team
    
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 org.acacia.csr.java;

import java.util.Iterator;

import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Partitioner;

public class VertexPartitioner implements Partitioner<LongWritable, Text> {
    private long numberOfVerts;

    //@Override
    //Here we need to identify the vertex count/largest veretx. Then we can decide what number of vertices will be in a partition. Then what we need to do is to
    //do a for loop and increment a counter until the key is in between the two incremented values. Once we find that condition satisfied, we return
    //the counter as the partition where the vertex record should be stored.
    public int getPartition(LongWritable key, Text values, int numReduceTasks) {
        int part = 0;
        long k = key.get();
        int vertsPerPart = -1;

        if (numReduceTasks > 1) {
            vertsPerPart = (int) (numberOfVerts / (numReduceTasks - 1));

            if (vertsPerPart != 0) {
                part = (int) (k / vertsPerPart);
            }
        }

        //System.out.println("vertex : " + k + " part : " + part);

        return part;
    }

    public void configure(JobConf arg0) {
        // TODO Auto-generated method stub
        numberOfVerts = Long.parseLong(arg0.get("vertex-count"));
    }
}