Java tutorial
/* * ClueWeb Tools: Hadoop tools for manipulating ClueWeb collections * * 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 io.bfscan.clueweb12; import io.bfscan.dictionary.DictionaryTransformationStrategy; import io.bfscan.util.QuickSort; import it.unimi.dsi.sux4j.mph.TwoStepsLcpMonotoneMinimalPerfectHashFunction; import it.unimi.dsi.util.FrontCodedStringList; import it.unimi.dsi.util.ShiftAddXorSignedStringMap; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.ObjectOutputStream; import java.util.Arrays; import java.util.Iterator; import java.util.List; 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.FSDataOutputStream; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.io.WritableUtils; 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.NullOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; import org.apache.log4j.Logger; import tl.lin.data.pair.PairOfIntLong; import com.google.common.collect.Lists; public class BuildDictionary extends Configured implements Tool { private static final Logger LOG = Logger.getLogger(BuildDictionary.class); private static final String HADOOP_OUTPUT_OPTION = "dictionary.path"; private static final String HADOOP_TERMS_COUNT_OPTION = "terms.count"; protected static enum Terms { Total } public static final String TERMS_DATA = "dictionary.terms"; public static final String TERMS_ID_DATA = "dictionary.ids"; public static final String TERMS_ID_MAPPING_DATA = "dictionary.mapping"; public static final String DF_BY_TERM_DATA = "df.terms"; public static final String DF_BY_ID_DATA = "df.ids"; public static final String CF_BY_TERM_DATA = "cf.terms"; public static final String CF_BY_ID_DATA = "cf.ids"; private static class MyReducer extends Reducer<Text, PairOfIntLong, NullWritable, NullWritable> { private FSDataOutputStream termsOut, idsOut, idsToTermOut, dfByTermOut, cfByTermOut, dfByIntOut, cfByIntOut; private int numTerms; private int[] seqNums = null; private int[] dfs = null; private long[] cfs = null; private int curKeyIndex = 0; private String[] terms; @Override public void setup(Reducer<Text, PairOfIntLong, NullWritable, NullWritable>.Context context) throws IOException { LOG.info("Starting setup."); Configuration conf = context.getConfiguration(); FileSystem fs = FileSystem.get(conf); numTerms = conf.getInt(HADOOP_TERMS_COUNT_OPTION, 0); LOG.info(HADOOP_TERMS_COUNT_OPTION + ": " + numTerms); String basePath = conf.get(HADOOP_OUTPUT_OPTION); LOG.info(HADOOP_OUTPUT_OPTION + ": " + basePath); terms = new String[numTerms]; seqNums = new int[numTerms]; dfs = new int[numTerms]; cfs = new long[numTerms]; termsOut = fs.create(new Path(basePath, TERMS_DATA), true); idsOut = fs.create(new Path(basePath, TERMS_ID_DATA), true); idsOut.writeInt(numTerms); idsToTermOut = fs.create(new Path(basePath, TERMS_ID_MAPPING_DATA), true); idsToTermOut.writeInt(numTerms); dfByTermOut = fs.create(new Path(basePath, DF_BY_TERM_DATA), true); dfByTermOut.writeInt(numTerms); cfByTermOut = fs.create(new Path(basePath, CF_BY_TERM_DATA), true); cfByTermOut.writeInt(numTerms); dfByIntOut = fs.create(new Path(basePath, DF_BY_ID_DATA), true); dfByIntOut.writeInt(numTerms); cfByIntOut = fs.create(new Path(basePath, CF_BY_ID_DATA), true); cfByIntOut.writeInt(numTerms); LOG.info("Finished setup."); } @Override public void reduce(Text key, Iterable<PairOfIntLong> values, Context context) throws IOException, InterruptedException { String term = key.toString(); Iterator<PairOfIntLong> iter = values.iterator(); PairOfIntLong p = iter.next(); int df = p.getLeftElement(); long cf = p.getRightElement(); WritableUtils.writeVInt(dfByTermOut, df); WritableUtils.writeVLong(cfByTermOut, cf); if (iter.hasNext()) { throw new RuntimeException("More than one record for term: " + term); } terms[curKeyIndex] = term; seqNums[curKeyIndex] = curKeyIndex; dfs[curKeyIndex] = -df; cfs[curKeyIndex] = cf; curKeyIndex++; context.getCounter(Terms.Total).increment(1); } @Override public void cleanup(Reducer<Text, PairOfIntLong, NullWritable, NullWritable>.Context context) throws IOException { LOG.info("Starting cleanup."); if (curKeyIndex != numTerms) { throw new RuntimeException( "Total expected Terms: " + numTerms + ", Total observed terms: " + curKeyIndex + "!"); } // Sort based on df and change seqNums accordingly. QuickSort.quicksortWithSecondary(seqNums, dfs, cfs, 0, numTerms - 1); // Write sorted dfs and cfs by int here. for (int i = 0; i < numTerms; i++) { WritableUtils.writeVInt(dfByIntOut, -dfs[i]); WritableUtils.writeVLong(cfByIntOut, cfs[i]); } cfs = null; // Encode the sorted dfs into ids ==> df values erased and become ids instead. Note that first // term id is 1. for (int i = 0; i < numTerms; i++) { dfs[i] = i + 1; } // Write current seq nums to be index into the term array. for (int i = 0; i < numTerms; i++) idsToTermOut.writeInt(seqNums[i]); // Sort on seqNums to get the right writing order. QuickSort.quicksort(dfs, seqNums, 0, numTerms - 1); for (int i = 0; i < numTerms; i++) { idsOut.writeInt(dfs[i]); } ByteArrayOutputStream bytesOut; ObjectOutputStream objOut; byte[] bytes; List<String> termList = Lists.newArrayList(terms); FrontCodedStringList frontcodedList = new FrontCodedStringList(termList, 8, true); bytesOut = new ByteArrayOutputStream(); objOut = new ObjectOutputStream(bytesOut); objOut.writeObject(frontcodedList); objOut.close(); bytes = bytesOut.toByteArray(); termsOut.writeInt(bytes.length); termsOut.write(bytes); ShiftAddXorSignedStringMap dict = new ShiftAddXorSignedStringMap(termList.iterator(), new TwoStepsLcpMonotoneMinimalPerfectHashFunction<CharSequence>(termList, DictionaryTransformationStrategy.getStrategy())); bytesOut = new ByteArrayOutputStream(); objOut = new ObjectOutputStream(bytesOut); objOut.writeObject(dict); objOut.close(); bytes = bytesOut.toByteArray(); termsOut.writeInt(bytes.length); termsOut.write(bytes); termsOut.close(); idsOut.close(); idsToTermOut.close(); dfByTermOut.close(); cfByTermOut.close(); dfByIntOut.close(); cfByIntOut.close(); LOG.info("Finished cleanup."); } } public static final String INPUT_OPTION = "input"; public static final String OUTPUT_OPTION = "output"; public static final String COUNT_OPTION = "count"; /** * 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_OPTION)); options.addOption( OptionBuilder.withArgName("path").hasArg().withDescription("output path").create(OUTPUT_OPTION)); options.addOption( OptionBuilder.withArgName("num").hasArg().withDescription("number of terms").create(COUNT_OPTION)); CommandLine cmdline; CommandLineParser parser = new GnuParser(); try { cmdline = parser.parse(options, args); } catch (ParseException exp) { HelpFormatter formatter = new HelpFormatter(); formatter.printHelp(this.getClass().getName(), options); ToolRunner.printGenericCommandUsage(System.out); System.err.println("Error parsing command line: " + exp.getMessage()); return -1; } if (!cmdline.hasOption(INPUT_OPTION) || !cmdline.hasOption(OUTPUT_OPTION) || !cmdline.hasOption(COUNT_OPTION)) { HelpFormatter formatter = new HelpFormatter(); formatter.printHelp(this.getClass().getName(), options); ToolRunner.printGenericCommandUsage(System.out); return -1; } String input = cmdline.getOptionValue(INPUT_OPTION); String output = cmdline.getOptionValue(OUTPUT_OPTION); LOG.info("Tool name: " + ComputeTermStatistics.class.getSimpleName()); LOG.info(" - input: " + input); LOG.info(" - output: " + output); Configuration conf = getConf(); conf.set(HADOOP_OUTPUT_OPTION, output); conf.setInt(HADOOP_TERMS_COUNT_OPTION, Integer.parseInt(cmdline.getOptionValue(COUNT_OPTION))); conf.set("mapreduce.map.memory.mb", "4096"); conf.set("mapreduce.map.java.opts", "-Xmx4096m"); conf.set("mapreduce.reduce.memory.mb", "4096"); conf.set("mapreduce.reduce.java.opts", "-Xmx4096m"); Job job = Job.getInstance(conf); job.setJobName(BuildDictionary.class.getSimpleName() + ":" + input); job.setJarByClass(BuildDictionary.class); job.setNumReduceTasks(1); FileInputFormat.setInputPaths(job, new Path(input)); FileOutputFormat.setOutputPath(job, new Path(output)); job.setInputFormatClass(SequenceFileInputFormat.class); job.setOutputFormatClass(NullOutputFormat.class); job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(PairOfIntLong.class); job.setOutputKeyClass(Text.class); job.setSortComparatorClass(DictionaryTransformationStrategy.WritableComparator.class); job.setMapperClass(Mapper.class); job.setReducerClass(MyReducer.class); FileSystem.get(getConf()).delete(new Path(output), true); long startTime = System.currentTimeMillis(); job.waitForCompletion(true); LOG.info("Job Finished in " + (System.currentTimeMillis() - startTime) / 1000.0 + " seconds"); return 0; } /** * Dispatches command-line arguments to the tool via the <code>ToolRunner</code>. */ public static void main(String[] args) throws Exception { LOG.info("Running " + BuildDictionary.class.getCanonicalName() + " with args " + Arrays.toString(args)); ToolRunner.run(new BuildDictionary(), args); } }