/**
 * Copyright 2015 Telefonica Investigación y Desarrollo, S.A.U
 *
 * This file is part of fiware-tidoop (FI-WARE project).
 *
 * fiware-tidoop is free software: you can redistribute it and/or modify it under the terms of the GNU Affero
 * General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 * fiware-tidoop is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Affero General Public License along with fiware-tidoop. If not, see
 * http://www.gnu.org/licenses/.
 *
 * For those usages not covered by the GNU Affero General Public License please contact with
 * francisco.romerobueno at telefonica dot com
 */
package com.telefonica.iot.tidoop.mrlib;

import com.telefonica.iot.tidoop.mrlib.utils.Constants;
import java.io.IOException;;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
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.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Logger;

/**
 *
 * @author frb
 */
public class MapOnly extends Configured implements Tool {
    
    private final static Logger logger = Logger.getLogger(MapOnly.class);
    
    /**
     * Mapper class.
     */
    public static class CustomMapper extends Mapper<Object, Text, NullWritable, Text> {
        
        private Function mapFunction = null;

        @Override
        public void setup(Context context) throws IOException, InterruptedException {
            mapFunction = new Function(context.getConfiguration().get(Constants.PARAM_FUNCTION, "long y = x"));
        } // setup

        @Override
        public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
            context.write(NullWritable.get(), mapFunction.eval(value));
        } // map
        
    } // CustomMapper
    
    /**
     * Main class.
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new Configuration(), new MapOnly(), args);
        System.exit(res);
    } // main
    
    @Override
    public int run(String[] args) throws Exception {
        // check the number of arguments, show the usage if it is wrong
        if (args.length != 3) {
            showUsage();
            return -1;
        } // if
        
        // get the arguments
        String input = args[0];
        String output = args[1];
        String mapFunction = args[2];
        
        // create and configure a MapReduce job
        Configuration conf = this.getConf();
        conf.set(Constants.PARAM_FUNCTION, mapFunction);
        Job job = Job.getInstance(conf, "tidoop-mr-lib-maponly");
        job.setNumReduceTasks(0);
        job.setJarByClass(MapOnly.class);
        job.setMapperClass(CustomMapper.class);
        job.setMapOutputKeyClass(NullWritable.class);
        job.setMapOutputValueClass(Text.class);
        job.setOutputKeyClass(NullWritable.class);
        job.setOutputValueClass(Text.class);
        FileInputFormat.addInputPath(job, new Path(input));
        FileOutputFormat.setOutputPath(job, new Path(output));
        
        // run the MapReduce job
        return job.waitForCompletion(true) ? 0 : 1;
    } // main
    
    private void showUsage() {
        System.out.println("Usage:");
        System.out.println();
        System.out.println("hadoop jar \\");
        System.out.println("   target/tidoop-mr-lib-x.y.z-jar-with-dependencies.jar \\");
        System.out.println("   com.telefonica.iot.tidoop.mrlib.MapOnly \\");
        System.out.println("   -libjars target/tidoop-mr-lib-x.y.z-jar-with-dependencies.jar \\");
        System.out.println("   <HDFS input> \\");
        System.out.println("   <HDFS output> \\");
        System.out.println("   <mapFunction>");
    } // showUsage
    
} // MapOnly

@@ -1052,17 +1052,16 @@
 ception;
-;
 %0Aimport 
@@ -1675,28 +1675,28 @@
 ate 
-final 
 static
+ final
  Logger 
 logg
@@ -1695,14 +1695,14 @@
 ger 
-logger
+LOGGER
  = L
@@ -2119,20 +2119,22 @@
 CTION, %22
-long
+double
  y = x%22)
@@ -4374,17 +4374,18 @@
 %22   %3Cmap
-F
+ f
 unction%3E

MODIFY the MapOnly class, minor changes