大数据（Storm）-WordCount

WordCountSplot

public class WCSpout extends BaseRichSpout{

    private SpoutOutputCollector collector;
    private String[] lines = {
            "this is first line",
            "this is second line",
            "this is third line"
    };

    @Override
    public void nextTuple() {
        Random random = new Random();
        System.out.println("aa");
        collector.emit(new Values(lines[random.nextInt(lines.length)]));
    }

    @SuppressWarnings("rawtypes")
    @Override
    public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
        this.collector = collector;
    }

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

}

WordCountSplitBlot

public class WCSplitBlot extends BaseRichBolt{
    private OutputCollector collector;
    @Override
    public void execute(Tuple tuple) {
        String line = tuple.getStringByField("line");
        String[] words = line.split(" ");
        for(String word : words) {
            collector.emit(new Values(word, 1));
        }
    }
    @Override
    public void prepare(Map conf, TopologyContext context, OutputCollector collector) {
        this.collector = collector;
    }
    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("word", "count"));
    }
}

WordCountCountBlot

public class WCCountBlot extends BaseRichBolt{
    private OutputCollector collector;
    private Map<String, Integer> map = new HashMap<String, Integer>();
    @Override
    public void execute(Tuple tuple) {
        String word = tuple.getStringByField("word");
        Integer count = tuple.getInteger(tuple.getIntegerByField("count"));
        if(!map.containsKey(word)) {
            map.put(word, count);
        }else{
            Integer currentCount = map.get(word);
            map.put(word, currentCount + count); 
        }
        System.out.println(map);
    }

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

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        //最终总计数量， 不输出结果
    }
}

MainTopology

public class WCTopology {

     public static void main( String[] args ) throws Exception {
         TopologyBuilder topologyBuilder = new TopologyBuilder();

         topologyBuilder.setSpout("mySpout",new WCSpout(),2);
         topologyBuilder.setBolt("mybolt1",new WCSplitBlot(),2).shuffleGrouping("mySpout");
         topologyBuilder.setBolt("mybolt2",new WCCountBlot(),4).fieldsGrouping("mybolt1", new Fields("word"));


          Config config =  new Config();
          config.setNumWorkers(2);

          //StormSubmitter.submitTopology("mywordcount",config,topologyBuilder.createTopology());
          LocalCluster localCluster = new LocalCluster();
          localCluster.submitTopology("mywordcount",config,topologyBuilder.createTopology());
    }
}