Storm实战之HelloWorld

官网建议首先是WordCount,个人觉得，如果学习，看代码可以是WordCount,但如果是个人写Topology,首先应该HelloWorld，然后是WordCount.

闲话少说，上代码：

package helloworld;

import backtype.storm.Config;
import backtype.storm.LocalCluster;
import backtype.storm.StormSubmitter;
import backtype.storm.topology.TopologyBuilder;

/**
 * 定义了一个简单的topology，包括一个数据喷发节点spout和一个数据处理节点bolt。
 * 
 * @author Administrator
 *
 */
public class SimpleTopology {
    public static void main(String[] args) {
        try {
         System.out.println("1111111111111111111");
            // 实例化TopologyBuilder类。
            TopologyBuilder topologyBuilder = new TopologyBuilder();
            // 设置喷发节点并分配并发数，该并发数将会控制该对象在集群中的线程数。
            topologyBuilder.setSpout("SimpleSpout", new SimpleSpout(), 1);
            // 设置数据处理节点并分配并发数。指定该节点接收喷发节点的策略为随机方式。
            topologyBuilder.setBolt("SimpleBolt", new SimpleBolt(), 2).shuffleGrouping("SimpleSpout");
            Config config = new Config();
            config.setDebug(true);
            System.out.println("2222222222222222");
            if (args != null && args.length > 0) {
                config.setNumWorkers(1);
                StormSubmitter.submitTopology(args[0], config, topologyBuilder.createTopology());
            } else {
                // 这里是本地模式下运行的启动代码。
             System.out.println("3333333333333333");
                config.setMaxTaskParallelism(1);
                LocalCluster cluster = new LocalCluster();
                cluster.submitTopology("simple", config, topologyBuilder.createTopology());
                System.out.println("444444444444444444");
            }
            
        } catch (Exception e) {
            e.printStackTrace(); 
        }
    }
}

Spout:

package helloworld;

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

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;

/**
 * Spout起到和外界沟通的作用，他可以从一个数据库中按照某种规则取数据，也可以从分布式队列中取任务
 * 
 * @author Administrator
 *
 *	数据源为内置的一个数组，随机在数组中选择一条发射
 */
@SuppressWarnings("serial")
public class SimpleSpout extends BaseRichSpout{
    //用来发射数据的工具类
    private SpoutOutputCollector collector;
    private static String[] info = new String[]{
        "comaple\t,12424,44w46,654,12424,44w46,654,",
        "lisi\t,435435,6537,12424,44w46,654,",
        "lipeng\t,45735,6757,12424,44w46,654,",
        "hujintao\t,45735,6757,12424,44w46,654,",
        "jiangmin\t,23545,6457,2455,7576,qr44453",
        "beijing\t,435435,6537,12424,44w46,654,",
        "xiaoming\t,46654,8579,w3675,85877,077998,",
        "xiaozhang\t,9789,788,97978,656,345235,09889,",
        "ceo\t,46654,8579,w3675,85877,077998,",
        "cto\t,46654,8579,w3675,85877,077998,",
        "zhansan\t,46654,8579,w3675,85877,077998,"};
    
    Random random=new Random();
    
    /**
     * 初始化collector
     */
    public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
    	System.out.println("5555555555555555555555");
        this.collector = collector;
        System.out.println("6666666666666");
    }
    
    /**
     * 在SpoutTracker类中被调用，每调用一次就可以向storm集群中发射一条数据（一个tuple元组），该方法会被不停的调用
     */
    @Override
    public void nextTuple() {
        try {
            String msg = info[random.nextInt(11)];
            // 调用发射方法
            System.out.println("777777777777777777");
            collector.emit(new Values(msg));
            System.out.println("8888888888888888");
            // 模拟等待100ms
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    /**
     * 定义字段id，该id在简单模式下没有用处，但在按照字段分组的模式下有很大的用处。
     * 该declarer变量有很大作用，我们还可以调用declarer.declareStream();来定义stramId，该id可以用来定义更加复杂的流拓扑结构
     */
    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
    	System.out.println("99999999999999");
        declarer.declare(new Fields("source")); //collector.emit(new Values(msg));参数要对应
        System.out.println("aaaaaaaaaaaaaaaa");
    }

}

Bolt:

package helloworld;

import backtype.storm.topology.BasicOutputCollector;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.topology.base.BaseBasicBolt;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Tuple;
import backtype.storm.tuple.Values;

/**
 * 接收喷发节点(Spout)发送的数据进行简单的处理后，发射出去。
 * 
 * @author Administrator
 * 
 */
@SuppressWarnings("serial")
public class SimpleBolt extends BaseBasicBolt {

    public void execute(Tuple input, BasicOutputCollector collector) {
        try {
            String msg = input.getString(0);
            if (msg != null){
                //System.out.println("msg="+msg);
                collector.emit(new Values(msg + "msg is processed!"));
            }
                
        } catch (Exception e) {
            e.printStackTrace(); 
        }
    }

    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        declarer.declare(new Fields("info"));
    }

}