com.jbw.recommendsystem.iteamlist.ItemMRD.java Source code

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Here is the source code for com.jbw.recommendsystem.iteamlist.ItemMRD.java

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package com.jbw.recommendsystem.iteamlist;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
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.iteamlist.ItemMRD -Dinput=/data/rmc/process/input/matrix.txt -Doutput=/user/jiabw/out/rs/item_1

/**
 *
 * @author alvin
 */
public class ItemMRD extends Configured implements Tool {

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

        private final FileParse parser = new FileParse();
        private final Text k = new Text();
        private final Text v = new Text();

        @Override
        protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
            parser.parse(value.toString());
            if (parser.isValid()) {
                k.set(parser.getGid());
                v.set(parser.getUid() + ":" + parser.getPre());
                context.write(k, v);
            }
        }
    }

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

        private final List<String> items = new ArrayList<>();

        @Override
        protected void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            items.clear();
            for (Text t : values) {
                items.add(t.toString());
            }
            context.write(key, new Text(items.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 surJob = Job.getInstance(conf);
        surJob.setJarByClass(ItemMRD.class);
        surJob.setJobName("item");

        surJob.setMapperClass(ItemMapper.class);
        surJob.setReducerClass(ItemReducer.class);

        surJob.setMapOutputKeyClass(Text.class);
        surJob.setMapOutputValueClass(Text.class);

        surJob.setOutputKeyClass(Text.class);
        surJob.setOutputValueClass(Text.class);

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

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

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

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