gistfile1.java

public class WordCount implements IBasicBolt {
    private Map<String, Integer> _counts = new HashMap<String, Integer>();

    public void prepare(Map conf, TopologyContext context) {
    }

    public void execute(Tuple tuple, BasicOutputCollector collector) {
        String word = tuple.getString(0);
        int count;
        if(_counts.containsKey(word)) {
            count = _counts.get(word);
        } else {
            count = 0;
        }
        count++;
        _counts.put(word, count);
        collector.emit(new Values(word, count));
    }

    public void cleanup() {
    }

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