Java tutorial
/* * 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.shrawanraina; import java.io.IOException; import java.util.ArrayList; import java.util.Arrays; import java.util.HashMap; import java.util.List; import java.util.Map; 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.IntWritable; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.input.TextInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.mapreduce.lib.output.SequenceFileOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; import org.apache.log4j.Logger; import tl.lin.data.array.ArrayListOfFloatsWritable; import tl.lin.data.array.ArrayListOfIntsWritable; /** * <p> * Driver program that takes a plain-text encoding of a directed graph and * builds corresponding Hadoop structures for representing the graph. * </p> * * @author Jimmy Lin * @author Michael Schatz */ public class BuildPersonalizedPageRankRecords extends Configured implements Tool { private static final Logger LOG = Logger.getLogger(BuildPersonalizedPageRankRecords.class); private static final String NODE_CNT_FIELD = "node.cnt"; private static Map<Integer, Integer> SOURCE_MAP = new HashMap<Integer, Integer>(); private static class MyMapper extends Mapper<LongWritable, Text, IntWritable, PageRankNodeUpd> { private static final IntWritable nid = new IntWritable(); private static final PageRankNodeUpd node = new PageRankNodeUpd(); @Override public void setup(Mapper<LongWritable, Text, IntWritable, PageRankNodeUpd>.Context context) { int n = context.getConfiguration().getInt(NODE_CNT_FIELD, 0); List<String> sourceList = Arrays.asList(context.getConfiguration().getStrings("sources")); System.out.println("<<<<<<<<list:" + sourceList); for (String src : sourceList) SOURCE_MAP.put(Integer.parseInt(src), sourceList.indexOf(src)); if (n == 0) { throw new RuntimeException(NODE_CNT_FIELD + " cannot be 0!"); } if (SOURCE_MAP.size() == 0) { throw new RuntimeException(SOURCE_MAP + " cannot be empty"); } node.setType(PageRankNodeUpd.Type.Complete); //node.setPageRank((float) -StrictMath.log(n)); } @Override public void map(LongWritable key, Text t, Context context) throws IOException, InterruptedException { String[] arr = t.toString().trim().split("\\s+"); float[] pagerank = new float[SOURCE_MAP.size()]; for (Integer source : SOURCE_MAP.keySet()) { int pos = SOURCE_MAP.get(source); if (node.getNodeId() == source) { //System.out.println("Pos: <<<<<<< "+pos); //System.out.println("Source: <<<<<<< "+source); pagerank[pos] = (float) StrictMath.log(1.0); //pagerank[pos] = (float) (1.0); //node.setPageRank((float) StrictMath.log(1.0)); } else { pagerank[pos] = (float) StrictMath.log(0.0); //pagerank[pos] = (float) (0.0); //node.setPageRank((float) StrictMath.log(0.0)); } } nid.set(Integer.parseInt(arr[0])); if (arr.length == 1) { node.setNodeId(Integer.parseInt(arr[0])); node.setAdjacencyList(new ArrayListOfIntsWritable()); } else { node.setNodeId(Integer.parseInt(arr[0])); int[] neighbors = new int[arr.length - 1]; for (int i = 1; i < arr.length; i++) { neighbors[i - 1] = Integer.parseInt(arr[i]); } node.setAdjacencyList(new ArrayListOfIntsWritable(neighbors)); } node.setPageRankList(new ArrayListOfFloatsWritable(pagerank)); context.getCounter("graph", "numNodes").increment(1); context.getCounter("graph", "numEdges").increment(arr.length - 1); if (arr.length > 1) { context.getCounter("graph", "numActiveNodes").increment(1); } //System.out.println("Id: 1 <<<<<<< "+nid); //System.out.println("pagerank: 1 <<<<<<< "+node.getPageRank()); //System.out.println("pagerankList: 1 <<<<<<< "+node.getPageRankList()); context.write(nid, node); } } public BuildPersonalizedPageRankRecords() { } private static final String INPUT = "input"; private static final String OUTPUT = "output"; private static final String NUM_NODES = "numNodes"; private static final String SOURCES = "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("number of nodes").create(NUM_NODES)); options.addOption( OptionBuilder.withArgName("node").hasArg().withDescription("source nodes").create(SOURCES)); 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(NUM_NODES) || !cmdline.hasOption(SOURCES)) { 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 = cmdline.getOptionValue(OUTPUT); int n = Integer.parseInt(cmdline.getOptionValue(NUM_NODES)); String sources = cmdline.getOptionValue(SOURCES); LOG.info("Tool name: " + BuildPersonalizedPageRankRecords.class.getSimpleName()); LOG.info(" - inputDir: " + inputPath); LOG.info(" - outputDir: " + outputPath); LOG.info(" - numNodes: " + n); LOG.info(" - sources: " + sources); Configuration conf = getConf(); conf.setInt(NODE_CNT_FIELD, n); conf.setStrings("sources", sources); conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024); Job job = Job.getInstance(conf); job.setJobName(BuildPersonalizedPageRankRecords.class.getSimpleName() + ":" + inputPath); job.setJarByClass(BuildPersonalizedPageRankRecords.class); job.setNumReduceTasks(0); FileInputFormat.addInputPath(job, new Path(inputPath)); FileOutputFormat.setOutputPath(job, new Path(outputPath)); job.setInputFormatClass(TextInputFormat.class); job.setOutputFormatClass(SequenceFileOutputFormat.class); job.setMapOutputKeyClass(IntWritable.class); job.setMapOutputValueClass(PageRankNodeUpd.class); job.setOutputKeyClass(IntWritable.class); job.setOutputValueClass(PageRankNodeUpd.class); job.setMapperClass(MyMapper.class); // Delete the output directory if it exists already. FileSystem.get(conf).delete(new Path(outputPath), true); job.waitForCompletion(true); return 0; } /** * Dispatches command-line arguments to the tool via the {@code ToolRunner}. */ public static void main(String[] args) throws Exception { ToolRunner.run(new BuildPersonalizedPageRankRecords(), args); } }