com.jbw.recommendsystem.add.AddMRD.java Source code

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Here is the source code for com.jbw.recommendsystem.add.AddMRD.java

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package com.jbw.recommendsystem.add;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
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.Reducer;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

// yarn jar target/RecommendSystem-0.jar com.jbw.recommendsystem.add.AddMRD -Dinput=/user/jiabw/out/rs/join_1/part-r-00000 -Doutput=/user/jiabw/out/rs/add_0
/**
 *
 * @author alvin
 */
public class AddMRD extends Configured implements Tool {

    static class AddMapper extends Mapper<LongWritable, Text, Text, Text> {

        @Override
        protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
            String[] dd = value.toString().split("\t");
            context.write(new Text(dd[0].trim()), new Text(dd[1].trim()));
        }

    }

    static class AddReducer extends Reducer<Text, Text, Text, Text> {

        @Override
        protected void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {

            Map<String, List<Double>> lm = new HashMap<>();
            for (Text t : values) {
                String s = t.toString();
                String ss = s.substring(1, s.length() - 1);
                String fs[] = ss.split(",");
                for (String st : fs) {
                    String hg[] = st.split(":");
                    if (lm.containsKey(hg[0].trim())) {
                        lm.get(hg[0].trim()).add(Double.parseDouble(hg[1].trim()));
                    } else {
                        List<Double> ll = new ArrayList<>();
                        ll.add(Double.parseDouble(hg[1].trim()));
                        lm.put(hg[0].trim(), ll);
                    }
                }
            }

            StringBuilder sb = new StringBuilder();
            sb.append("[");
            for (String fd : lm.keySet()) {
                double sum = 0;
                for (Double dd : lm.get(fd)) {
                    sum += dd;
                }
                sb.append(fd).append(":").append(sum).append(",");
            }
            sb.delete(sb.length() - 1, sb.length());
            sb.append("]");
            context.write(key, new Text(sb.toString()));
        }

    }

    @Override
    public int run(String[] strings) throws Exception {
        Configuration conf = getConf();
        Path in = new Path(conf.get("input"));
        Path out = new Path(conf.get("output"));

        Job job = Job.getInstance(conf);
        job.setJobName("5");
        job.setJarByClass(AddMRD.class);

        job.setMapperClass(AddMapper.class);
        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(Text.class);

        job.setReducerClass(AddReducer.class);
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(Text.class);

        job.setInputFormatClass(TextInputFormat.class);
        job.setOutputFormatClass(TextOutputFormat.class);

        TextInputFormat.addInputPath(job, in);
        TextOutputFormat.setOutputPath(job, out);

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

    public static void main(String[] args) throws Exception {
        System.exit(ToolRunner.run(new AddMRD(), args));
    }
}