examples/storm-starter/src/jvm/org/apache/storm/starter/spout/RandomIntegerSpout.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The ASF licenses this file to you 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
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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 org.apache.storm.starter.spout;

import java.util.Map;
import java.util.Random;
import org.apache.storm.spout.SpoutOutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.topology.base.BaseRichSpout;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Values;
import org.apache.storm.utils.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Emits a random integer and a timestamp value (offset by one day),
 * every 100 ms. The ts field can be used in tuple time based windowing.
 */
public class RandomIntegerSpout extends BaseRichSpout {
    private static final Logger LOG = LoggerFactory.getLogger(RandomIntegerSpout.class);
    private SpoutOutputCollector collector;
    private Random rand;
    private long msgId = 0;

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("value", "ts", "msgid"));
    }

    @Override
    public void open(Map<String, Object> conf, TopologyContext context, SpoutOutputCollector collector) {
        this.collector = collector;
        this.rand = new Random();
    }

    @Override
    public void nextTuple() {
        Utils.sleep(100);
        collector.emit(new Values(rand.nextInt(1000), System.currentTimeMillis() - (24 * 60 * 60 * 1000), ++msgId), msgId);
    }

    @Override
    public void ack(Object msgId) {
        LOG.debug("Got ACK for msgId : " + msgId);
    }

    @Override
    public void fail(Object msgId) {
        LOG.debug("Got FAIL for msgId : " + msgId);
    }
}