org.apache.accumulo.examples.mapreduce.NGramIngest.java Source code

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Here is the source code for org.apache.accumulo.examples.mapreduce.NGramIngest.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.accumulo.examples.mapreduce;

import java.io.IOException;
import java.util.SortedSet;
import java.util.TreeSet;

import org.apache.accumulo.core.client.mapreduce.AccumuloOutputFormat;
import org.apache.accumulo.core.data.Mutation;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.examples.cli.MapReduceClientOnRequiredTable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
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.TextInputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.beust.jcommander.Parameter;

/**
 * Map job to ingest n-gram files from http://storage.googleapis.com/books/ngrams/books/datasetsv2.html
 */
public class NGramIngest extends Configured implements Tool {

    private static final Logger log = LoggerFactory.getLogger(NGramIngest.class);

    static class Opts extends MapReduceClientOnRequiredTable {
        @Parameter(names = "--input", required = true)
        String inputDirectory;
    }

    static class NGramMapper extends Mapper<LongWritable, Text, Text, Mutation> {

        @Override
        protected void map(LongWritable location, Text value, Context context)
                throws IOException, InterruptedException {
            String parts[] = value.toString().split("\\t");
            if (parts.length >= 4) {
                Mutation m = new Mutation(parts[0]);
                m.put(parts[1], String.format("%010d", Long.parseLong(parts[2])),
                        new Value(parts[3].trim().getBytes()));
                context.write(null, m);
            }
        }
    }

    @Override
    public int run(String[] args) throws Exception {
        Opts opts = new Opts();
        opts.parseArgs(getClass().getName(), args);

        Job job = Job.getInstance(getConf());
        job.setJobName(getClass().getSimpleName());
        job.setJarByClass(getClass());

        opts.setAccumuloConfigs(job);
        job.setInputFormatClass(TextInputFormat.class);
        job.setOutputFormatClass(AccumuloOutputFormat.class);

        job.setMapperClass(NGramMapper.class);
        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(Mutation.class);

        job.setNumReduceTasks(0);
        job.setSpeculativeExecution(false);

        if (!opts.getConnector().tableOperations().exists(opts.getTableName())) {
            log.info("Creating table " + opts.getTableName());
            opts.getConnector().tableOperations().create(opts.getTableName());
            SortedSet<Text> splits = new TreeSet<>();
            String numbers[] = "1 2 3 4 5 6 7 8 9".split("\\s");
            String lower[] = "a b c d e f g h i j k l m n o p q r s t u v w x y z".split("\\s");
            String upper[] = "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z".split("\\s");
            for (String[] array : new String[][] { numbers, lower, upper }) {
                for (String s : array) {
                    splits.add(new Text(s));
                }
            }
            opts.getConnector().tableOperations().addSplits(opts.getTableName(), splits);
        }

        TextInputFormat.addInputPath(job, new Path(opts.inputDirectory));
        job.waitForCompletion(true);
        return job.isSuccessful() ? 0 : 1;
    }

    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new Configuration(), new NGramIngest(), args);
        if (res != 0)
            System.exit(res);
    }

}