content: /**
   * 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.apex.examples.mroperator;
  
  import java.io.IOException;
  import java.util.Iterator;
  import java.util.StringTokenizer;
  
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.io.LongWritable;
  import org.apache.hadoop.io.Text;
  import org.apache.hadoop.mapred.FileInputFormat;
  import org.apache.hadoop.mapred.FileOutputFormat;
  import org.apache.hadoop.mapred.FileSplit;
  import org.apache.hadoop.mapred.JobClient;
  import org.apache.hadoop.mapred.JobConf;
  import org.apache.hadoop.mapred.MapReduceBase;
  import org.apache.hadoop.mapred.Mapper;
  import org.apache.hadoop.mapred.OutputCollector;
  import org.apache.hadoop.mapred.Reducer;
  import org.apache.hadoop.mapred.Reporter;
  
  /**
   * <p>LineIndexer class.</p>
   *
   * @since 0.9.0
   */
  public class LineIndexer
  {
  
    public static class LineIndexMapper extends MapReduceBase
        implements Mapper<LongWritable, Text, Text, Text>
    {
      private static final Text word = new Text();
      private static final Text location = new Text();
  
      public void map(LongWritable key, Text val,
          OutputCollector<Text, Text> output, Reporter reporter) throws IOException
      {
        FileSplit fileSplit = (FileSplit)reporter.getInputSplit();
        String fileName = fileSplit.getPath().getName();
        location.set(fileName);
  
        String line = val.toString();
        StringTokenizer itr = new StringTokenizer(line.toLowerCase());
        while (itr.hasMoreTokens()) {
          word.set(itr.nextToken());
          output.collect(word, location);
        }
      }
    }
  
  
  
    public static class LineIndexReducer extends MapReduceBase
        implements Reducer<Text, Text, Text, Text>
    {
      public void reduce(Text key, Iterator<Text> values,
          OutputCollector<Text, Text> output, Reporter reporter) throws IOException
      {
        boolean first = true;
        StringBuilder toReturn = new StringBuilder();
        while (values.hasNext()) {
          if (!first) {
            toReturn.append(", ");
          }
          first = false;
          toReturn.append(values.next().toString());
        }
  
        output.collect(key, new Text(toReturn.toString()));
      }
    }
  
  
    /**
     * The actual main() method for our program; this is the
     * "driver" for the MapReduce job.
     */
    public static void main(String[] args)
    {
      JobClient client = new JobClient();
      JobConf conf = new JobConf(LineIndexer.class);
  
      conf.setJobName("LineIndexer");
  
      conf.setOutputKeyClass(Text.class);
      conf.setOutputValueClass(Text.class);
  
      FileInputFormat.addInputPath(conf, new Path("input"));
      FileOutputFormat.setOutputPath(conf, new Path("output"));
  
      conf.setMapperClass(LineIndexMapper.class);
      conf.setReducerClass(LineIndexReducer.class);
  
      client.setConf(conf);
  
      try {
        JobClient.runJob(conf);
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
  }
  