com.antbrains.crf.hadoop.InstanceGenerator.java Source code

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Here is the source code for com.antbrains.crf.hadoop.InstanceGenerator.java

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/**
 *  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 com.antbrains.crf.hadoop;

import gnu.trove.map.hash.TObjectIntHashMap;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.URI;

import org.apache.commons.codec.binary.Base64;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.filecache.DistributedCache;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;

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.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;

import com.antbrains.crf.BESB1B2MTagConvertor;
import com.antbrains.crf.FeatureDict;
import com.antbrains.crf.Instance;
import com.antbrains.crf.SgdCrf;
import com.antbrains.crf.TagConvertor;
import com.antbrains.crf.Template;
import com.google.gson.Gson;

import de.ruedigermoeller.serialization.FSTObjectInput;

public class InstanceGenerator {

    public static class CounterMapper extends Mapper<Object, Text, IntWritable, Text> {
        private FeatureDict fd = null;
        private Template template;
        private TagConvertor tc = new BESB1B2MTagConvertor();
        private TObjectIntHashMap<String> labelDict;
        private int reducerNum = 100;
        private long lineNumber = 0;
        private Gson gson = new Gson();

        @Override
        protected void setup(Context context) throws IOException, InterruptedException {
            FSTObjectInput foi = null;
            String dict = context.getConfiguration().get("dict");
            if (dict == null)
                throw new IOException("dict is null");
            Path[] paths = DistributedCache.getLocalCacheFiles(context.getConfiguration());
            if (paths.length != 1)
                throw new IOException("paths.length=" + paths.length);
            try {
                foi = new FSTObjectInput(new FileInputStream(paths[0].toString()));
                try {
                    fd = (FeatureDict) foi.readObject();
                    int size = fd.size();
                    context.getCounter(InstanceGenerator.class.getSimpleName(), "" + size).increment(1);
                } catch (ClassNotFoundException e) {
                    throw new IOException(e);
                }

            } finally {
                if (foi != null) {
                    foi.close();
                }
            }
            labelDict = new TObjectIntHashMap<String>();
            for (String tag : tc.getTags()) {
                labelDict.put(tag, labelDict.size());
            }
            try {
                template = (Template) string2Object(context.getConfiguration().get("template"));
            } catch (ClassNotFoundException e) {
                throw new IOException(e);
            }
            // reducerNum = context.getConfiguration().getInt("mapred.map.tasks",
            // reducerNum);
        }

        @Override
        protected void cleanup(final Context context) throws IOException, InterruptedException {
            // lineNumber=0;
        }

        @Override
        public void map(Object key, Text value, final Context context) throws IOException, InterruptedException {
            String[] tks = value.toString().split("\t");
            Instance instance = SgdCrf.buildInstance(tks, tc, fd, labelDict, template, false, false);
            int k = (int) ((lineNumber++) % this.reducerNum);
            context.write(new IntWritable(k), new Text(gson.toJson(instance)));
        }
    }

    public static String object2String(Object o) throws IOException {
        ByteArrayOutputStream bo = new ByteArrayOutputStream();
        ObjectOutputStream so = new ObjectOutputStream(bo);
        so.writeObject(o);
        so.flush();
        byte[] arr = Base64.encodeBase64(bo.toByteArray());
        return new String(arr, "UTF8");
    }

    public static Object string2Object(String s) throws IOException, ClassNotFoundException {
        byte b[] = s.getBytes("UTF8");
        byte[] bytes = Base64.decodeBase64(b);
        ByteArrayInputStream bi = new ByteArrayInputStream(bytes);
        ObjectInputStream si = new ObjectInputStream(bi);
        return si.readObject();
    }

    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();
        String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
        if (otherArgs.length != 4) {
            System.err.println("InstanceGenerator <in> <out> <featuredict> <template>");
            System.exit(-1);
        }
        Template template = new Template(otherArgs[3], "UTF8");
        conf.set("template", object2String(template));
        // conf.set("tc", object2String(tc));

        DistributedCache.addCacheFile(new URI(otherArgs[2]), conf);
        conf.set("dict", otherArgs[2]);
        conf.set("mapred.reduce.tasks", "0");
        Job job = new Job(conf, InstanceGenerator.class.getSimpleName());

        job.setJarByClass(InstanceGenerator.class);
        job.setMapperClass(CounterMapper.class);

        job.setOutputKeyClass(IntWritable.class);
        job.setOutputValueClass(Text.class);
        FileInputFormat.addInputPath(job, new Path(otherArgs[0]));
        FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));

        System.exit(job.waitForCompletion(true) ? 0 : 1);
    }
}