examples/storm-mongodb-examples/src/main/java/org/apache/storm/mongodb/topology/WordSpout.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.mongodb.topology;

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

import org.apache.storm.spout.SpoutOutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.IRichSpout;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Values;

public class WordSpout implements IRichSpout {
    boolean isDistributed;
    SpoutOutputCollector collector;
    public static final String[] words = new String[] { "apple", "orange", "pineapple", "banana", "watermelon" };

    public WordSpout() {
        this(true);
    }

    public WordSpout(boolean isDistributed) {
        this.isDistributed = isDistributed;
    }

    public boolean isDistributed() {
        return this.isDistributed;
    }

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

    @Override
    public void close() {

    }

    @Override
    public void nextTuple() {
        final Random rand = new Random();
        final String word = words[rand.nextInt(words.length)];
        this.collector.emit(new Values(word), UUID.randomUUID());
        Thread.yield();
    }

    @Override
    public void ack(Object msgId) {

    }

    @Override
    public void fail(Object msgId) {

    }

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

    @Override
    public void activate() {
    }

    @Override
    public void deactivate() {
    }

    @Override
    public Map<String, Object> getComponentConfiguration() {
        return null;
    }
}