RandomSentenceSpout.java

/**
 * Random Sentence Spout is a spout which generates tuples of sentences randomly.
 *
 * @author Tarun Sharma
 * @version 1.0
 * @see <a href="http://www.dream-lab.in/">DREAM:Lab</a>
 * <p/>
 * Copyright 2014 DREAM:Lab, Indian Institute of Science, 2014
 * <p/>
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package mypackage.spouts;

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 org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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

public class RandomSentenceSpout extends BaseRichSpout {
    /**
     *
     */
    private static final long serialVersionUID = 3747139112340179001L;
    private static Logger LOG = LoggerFactory.getLogger(RandomSentenceSpout.class);
    SpoutOutputCollector collector;
    Random r;
    long myRandomMsgId;


    @Override
    public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
        this.collector = collector;
        this.r = 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"};
        String sentence = sentences[r.nextInt(sentences.length)];
        //this.collector.emit(new Values(sentence));
        //long myMessage = Long.decode("0xfe00000000000000");
        myRandomMsgId++;
        if (myRandomMsgId > 5) myRandomMsgId = 1;
        LOG.info("The value of in RandomSentenceSpout is " + myRandomMsgId);
        //this.collector.emit(new Values(sentence), myRandomMsgId);
        this.collector.emit(new Values(sentence), myRandomMsgId);
    }

    @Override
    public void ack(Object id) {
        LOG.info("The ACK value of in RandomSentenceSpout is " + id);
    }

    @Override
    public void fail(Object id) {
    }

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

}