RandomSentenceSpout.java

package udacity.storm.spout;

import backtype.storm.spout.SpoutOutputCollector;
import backtype.storm.task.TopologyContext;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.topology.base.BaseRichSpout;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;
import backtype.storm.utils.Utils;

import java.util.Map;
import java.util.Random;

public class RandomSentenceSpout extends BaseRichSpout {
  SpoutOutputCollector _collector;
  Random _rand;


  @Override
  public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
    _collector = collector;
    _rand = new Random();
  }

  @Override
  public void nextTuple() {
    Utils.sleep(100);
    String[] sentences = new String[]{
      /* "the cow jumped over the moon",
      "an apple a day keeps the doctor away",
      "four score and seven years ago",
      "snow white and the seven dwarfs",
      "i am at two with nature" */
      "hello, everyone, and thank you for joining us",
      "we have a lot of news to share with you today",
      "i'd like to talk about our business and the road ahead",
      "we're now half way through our fiscal 2013",
      "we've introduced and ramped production of",
      "our revenue for the first half was over $98 billion",
      "during that time we sold 85 m iphones and 42 m ipads",
      "these are very, very large numbers",
      "despite producing results that met or beat our guidance"
      };
    String sentence = sentences[_rand.nextInt(sentences.length)];
    _collector.emit(new Values(sentence));
  }

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