RollingTopWords.java

package com.realtimecep.storm.starter;

import backtype.storm.Config;
import backtype.storm.LocalCluster;
import backtype.storm.testing.TestWordSpout;
import backtype.storm.topology.TopologyBuilder;
import backtype.storm.tuple.Fields;
import com.realtimecep.storm.starter.bolts.MergeObjects;
import com.realtimecep.storm.starter.bolts.RankObjects;
import com.realtimecep.storm.starter.bolts.RollingCountObjects;


/**
 * 1차로 랭킹을 뽑고 topN을 모아서 topN을 뽑는다.
 *
 * This topology does a continuous computation of the top N words that the topology has seen
 * in terms of cardinality. The top N computation is done in a completely scalable way, and
 * a similar approach could be used to compute things like trending topics or trending images
 * on Twitter.
 */
public class RollingTopWords {

    public static void main(String[] args) throws Exception {

        final int TOP_N = 4;

        TopologyBuilder builder = new TopologyBuilder();

        builder.setSpout("word", new TestWordSpout(), 5);

        builder.setBolt("count", new RollingCountObjects(60, 10), 4)
                .fieldsGrouping("word", new Fields("word"));
        builder.setBolt("rank", new RankObjects(TOP_N), 4)
                .fieldsGrouping("count", new Fields("obj"));
        builder.setBolt("merge", new MergeObjects(TOP_N))
                .globalGrouping("rank");



        Config conf = new Config();
        conf.setDebug(true);

        LocalCluster cluster = new LocalCluster();
        cluster.submitTopology("rolling-demo", conf, builder.createTopology());
//        Thread.sleep(10000);

//        cluster.shutdown();

    }
}