global分组
        对目标target tasked进行排序，选择最小的taskId号进行发送tuple
        类似于direct,可以是特殊的direct分组。

package com.mao.storm.group.global;

import org.apache.storm.Config;
import org.apache.storm.LocalCluster;
import org.apache.storm.topology.TopologyBuilder;

/**
 * global是direct分组的特例，选择最小的taskId
 */
public class App {
    public static void main(String[] args) throws Exception {
        TopologyBuilder builder = new TopologyBuilder();
        //设置Spout
        builder.setSpout("wcspout", new WordCountSpout()).setNumTasks(2);
        //设置creator-Bolt
        builder.setBolt("split-bolt", new SplitBolt(),2).noneGrouping("wcspout").setNumTasks(2);

        Config conf = new Config();
        conf.setNumWorkers(2);
        conf.setDebug(true);

        /**
         * 本地模式storm
         */
        LocalCluster cluster = new LocalCluster();
        cluster.submitTopology("wc", conf, builder.createTopology());
        System.out.println("hello world");
        //Thread.sleep(20000);
//        StormSubmitter.submitTopology("wordcount", conf, builder.createTopology());
        //cluster.shutdown();

    }
}

package com.mao.storm.group.global;

import com.mao.storm.util.Util;
import org.apache.storm.task.OutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.IRichBolt;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Tuple;
import org.apache.storm.tuple.Values;

import java.util.Map;

/**
 */
public class SplitBolt implements IRichBolt {

    private TopologyContext context ;
    private OutputCollector collector ;

    public void prepare(Map stormConf, TopologyContext context, OutputCollector collector) {
        this.context = context ;
        this.collector = collector ;
    }

    public void execute(Tuple tuple) {
        String line = tuple.getString(0);
        Util.sendToLocalhost(this,line);
        String[] arr = line.split(" ");
        for(String s : arr){
            collector.emit(new Values(s,1));
        }
    }

    public void cleanup() {

    }

    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("word","count"));

    }

    public Map<String, Object> getComponentConfiguration() {
        return null;
    }
}

package com.mao.storm.group.global;

import org.apache.storm.spout.SpoutOutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.IRichSpout;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Values;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Random;

/**
 * Spout
 */
public class WordCountSpout implements IRichSpout{
    private TopologyContext context ;
    private SpoutOutputCollector collector ;

    private List<String> states ;

    private Random r = new Random();

    private int index = 0;

    public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
        this.context = context ;
        this.collector = collector ;
        states = new ArrayList<String>();
        states.add("hello world tom");
        states.add("hello world tomas");
        states.add("hello world tomasLee");
        states.add("hello world tomson");
    }

    public void close() {

    }

    public void activate() {

    }

    public void deactivate() {

    }

    public void nextTuple() {
        if(index < 3){
            String line = states.get(r.nextInt(4));
            collector.emit(new Values(line),index);
            index ++ ;
        }
    }

    public void ack(Object msgId) {
    }

    public void fail(Object msgId) {

    }

    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("line"));
    }

    public Map<String, Object> getComponentConfiguration() {
        return null;
    }
}