edu.umd.honghongie.ExtractTopPersonalizedPageRankNodes.java Source code

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/*
 * Cloud9: A Hadoop toolkit for working with big data
 *
 * 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 edu.umd.honghongie;

import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.GnuParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.FloatWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Logger;

import tl.lin.data.pair.PairOfObjectFloat;
import tl.lin.data.queue.TopScoredObjects;
import tl.lin.data.array.ArrayListOfInts;
import tl.lin.data.array.ArrayListOfFloatsWritable;

public class ExtractTopPersonalizedPageRankNodes extends Configured implements Tool {
    private static final Logger LOG = Logger.getLogger(ExtractTopPersonalizedPageRankNodes.class);

    private static class MyMapper extends Mapper<IntWritable, PageRankNode, IntWritable, FloatWritable> {
        private TopScoredObjects<Integer> queue;
        private int times;

        @Override
        public void setup(Context context) throws IOException {
            int k = context.getConfiguration().getInt("n", 100);
            times = context.getConfiguration().getInt("times", 0); //****
            queue = new TopScoredObjects<Integer>(k);
        }

        @Override
        public void map(IntWritable nid, PageRankNode node, Context context)
                throws IOException, InterruptedException {
            ArrayListOfFloatsWritable pagerankvalues = node.getPageRank();
            queue.add(node.getNodeId(), pagerankvalues.get(times));
        }

        @Override
        public void cleanup(Context context) throws IOException, InterruptedException {
            IntWritable key = new IntWritable();
            FloatWritable value = new FloatWritable();

            for (PairOfObjectFloat<Integer> pair : queue.extractAll()) {
                key.set(pair.getLeftElement());
                value.set(pair.getRightElement());
                context.write(key, value);
            }
        }
    }

    private static class MyReducer extends Reducer<IntWritable, FloatWritable, IntWritable, FloatWritable> {
        private static TopScoredObjects<Integer> queue;
        private int sourceid; //***

        @Override
        public void setup(Context context) throws IOException {
            int k = context.getConfiguration().getInt("n", 100);
            queue = new TopScoredObjects<Integer>(k);
            sourceid = context.getConfiguration().getInt("source", 0); //***

        }

        @Override
        public void reduce(IntWritable nid, Iterable<FloatWritable> iterable, Context context) throws IOException {
            Iterator<FloatWritable> iter = iterable.iterator();
            float pagerank = (float) StrictMath.exp(iter.next().get()); // transform to normal pagerank value
            queue.add(nid.get(), pagerank);

            // Shouldn't happen. Throw an exception.
            if (iter.hasNext()) {
                throw new RuntimeException();
            }
        }

        @Override
        public void cleanup(Context context) throws IOException, InterruptedException {
            IntWritable key = new IntWritable();
            FloatWritable value = new FloatWritable();

            System.out.println("Source: " + sourceid);

            for (PairOfObjectFloat<Integer> pair : queue.extractAll()) {
                key.set(pair.getLeftElement());
                value.set(pair.getRightElement());
                context.write(key, value);

                float pagerank = pair.getRightElement();
                int thenodeid = pair.getLeftElement();
                String ss = String.format("%.5f %d", pagerank, thenodeid);
                System.out.println(ss);

            }
        }
    }

    public ExtractTopPersonalizedPageRankNodes() {
    }

    private static final String INPUT = "input";
    private static final String OUTPUT = "output";
    private static final String TOP = "top";
    private static final String SOURCE = "sources";

    /**
     * Runs this tool.
     */
    @SuppressWarnings({ "static-access" })
    public int run(String[] args) throws Exception {
        Options options = new Options();

        options.addOption(OptionBuilder.withArgName("path").hasArg().withDescription("input path").create(INPUT));
        //  options.addOption(OptionBuilder.withArgName("path").hasArg()
        //      .withDescription("output path").create(OUTPUT));
        options.addOption(OptionBuilder.withArgName("num").hasArg().withDescription("top n").create(TOP));
        //******
        options.addOption(
                OptionBuilder.withArgName("node").hasArg().withDescription("source nodes").create(SOURCE));

        CommandLine cmdline;
        CommandLineParser parser = new GnuParser();

        try {
            cmdline = parser.parse(options, args);
        } catch (ParseException exp) {
            System.err.println("Error parsing command line: " + exp.getMessage());
            return -1;
        }

        if (!cmdline.hasOption(INPUT) || //!cmdline.hasOption(OUTPUT) || 
                !cmdline.hasOption(TOP) || !cmdline.hasOption(SOURCE)) //source node
        {
            System.out.println("args: " + Arrays.toString(args));
            HelpFormatter formatter = new HelpFormatter();
            formatter.setWidth(120);
            formatter.printHelp(this.getClass().getName(), options);
            ToolRunner.printGenericCommandUsage(System.out);
            return -1;
        }

        String inputPath = cmdline.getOptionValue(INPUT);

        String outputPath = "TestOutput"; //*********????

        int n = Integer.parseInt(cmdline.getOptionValue(TOP));
        //*******
        String nodeid = cmdline.getOptionValue(SOURCE);

        ArrayListOfInts sourceids = new ArrayListOfInts();
        String ss[] = nodeid.split(",");
        for (int i = 0; i < ss.length; i++) {
            sourceids.add(Integer.parseInt(ss[i]));
        }

        LOG.info("Tool name: " + ExtractTopPersonalizedPageRankNodes.class.getSimpleName());
        LOG.info(" - input: " + inputPath);
        LOG.info(" - output: " + outputPath);
        LOG.info(" - top: " + n);
        LOG.info(" - source node: " + nodeid);

        for (int i = 0; i < sourceids.size(); i++) {
            int source = sourceids.get(i);
            iterateSort(i, source, n, inputPath, outputPath); //times, sourcenode, top n
        }

        return 0;
    }

    //run each iteration
    private void iterateSort(int i, int source, int n, String input, String output) throws Exception {

        Configuration conf = getConf();
        conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
        conf.setInt("n", n);
        conf.setInt("times", i);
        conf.setInt("source", source);

        Job job = Job.getInstance(conf);
        job.setJobName(ExtractTopPersonalizedPageRankNodes.class.getName() + ":" + input);
        job.setJarByClass(ExtractTopPersonalizedPageRankNodes.class);

        job.setNumReduceTasks(1);

        FileInputFormat.addInputPath(job, new Path(input));
        FileOutputFormat.setOutputPath(job, new Path(output + Integer.toString(i)));

        job.setInputFormatClass(SequenceFileInputFormat.class);
        job.setOutputFormatClass(TextOutputFormat.class);

        job.setMapOutputKeyClass(IntWritable.class);
        job.setMapOutputValueClass(FloatWritable.class);

        job.setOutputKeyClass(IntWritable.class);
        job.setOutputValueClass(FloatWritable.class);

        job.setMapperClass(MyMapper.class);
        job.setReducerClass(MyReducer.class);

        // Delete the output directory if it exists already.
        FileSystem.get(conf).delete(new Path(output + Integer.toString(i)), true);

        long startTime = System.currentTimeMillis();
        job.waitForCompletion(true);
        System.out.println("Job Finished in " + (System.currentTimeMillis() - startTime) / 1000.0 + " seconds");

    }

    /**
     * Dispatches command-line arguments to the tool via the {@code ToolRunner}.
     */
    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new ExtractTopPersonalizedPageRankNodes(), args);
        System.exit(res);
    }
}