org.sf.xrime.algorithms.transform.vertex.Vertex2LabeledMapper.java Source code

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Here is the source code for org.sf.xrime.algorithms.transform.vertex.Vertex2LabeledMapper.java

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/*
 * Copyright (C) IBM Corp. 2009.
 * 
 * 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.sf.xrime.algorithms.transform.vertex;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.sf.xrime.model.label.LabelAdder;
import org.sf.xrime.model.label.Labelable;
import org.sf.xrime.model.vertex.Vertex;
import org.sf.xrime.model.vertex.VertexUtils;

/**
 * Mapper used to transform vertexes to vertexes with labels.
 */
public class Vertex2LabeledMapper extends MapReduceBase implements Mapper<Text, Vertex, Text, Vertex> {

    protected LabelAdder theLabelAdder = null;
    Configuration conf;

    @Override
    public void map(Text key, Vertex value, OutputCollector<Text, Vertex> output, Reporter reporter)
            throws IOException {
        Vertex vertex = (Vertex) VertexUtils.getLabledVertex(value);

        if (theLabelAdder != null) {
            theLabelAdder.addLabels((Labelable) vertex, vertex);
        }

        output.collect(key, vertex);
    }

    public void configure(JobConf job) {
        super.configure(job);

        conf = job;

        Class<? extends LabelAdder> labelAdderClass = job.getClass(Vertex2LabeledTransformer.labelFactoryKey, null,
                LabelAdder.class);
        try {
            if (labelAdderClass == null) {
                // Allow null label adder, i.e., allow Labeled objects with empty initial label set.
                theLabelAdder = null;
            } else {
                theLabelAdder = labelAdderClass.newInstance();
                theLabelAdder.configure(job);
            }
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }

    public void close() throws IOException {
        if (theLabelAdder != null) {
            theLabelAdder.close();
        }
        super.close();
    }
}