Storm整合Kafka Java API源码

1.Maven项目的pom.xml源码如下:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.yg</groupId>
    <artifactId>storm</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>storm</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>

        <dependency>
            <groupId>org.apache.storm</groupId>
            <artifactId>storm-core</artifactId>
            <version>1.1.3</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka_2.12</artifactId>
            <version>0.10.2.1</version>
        </dependency>

        <dependency>
            <groupId>org.apache.storm</groupId>
            <artifactId>storm-kafka</artifactId>
            <version>1.1.3</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <configuration>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                    <archive>
                        <manifest>
                            <mainClass>com.path.to.main.Class</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>

        </plugins>
    </build>

</project>

2.KafkaSpout.java源码如下:

package com.yg.storm.kafka.spouts;

import java.util.Arrays;
import java.util.Map;
import java.util.Properties;

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
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;

public class KafkaSpout extends BaseRichSpout {

    private static final long serialVersionUID = 7582771881226024741L;
    private KafkaConsumer<String, String> consumer;
    final private String TOPIC = "myTopic";
    SpoutOutputCollector collector;

    @Override
    public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
        this.collector = collector;

        Properties props = new Properties();
        props.put("bootstrap.servers", "hadoop211:9092,hadoop212:9092,hadoop213:9092");
        props.put("group.id", "test");
        props.put("enable.auto.commit", "true");
        props.put("auto.commit.interval.ms", "1000");
        props.put("session.timeout.ms", "30000");
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        consumer = new KafkaConsumer<String, String>(props);
        consumer.subscribe(Arrays.asList(TOPIC));

    }

    @Override
    public void nextTuple() {
        try {
            consumer.subscribe(Arrays.asList(TOPIC));//向topic订阅数据

            //无限循环拉取
            while (true) {
                ConsumerRecords<String, String> records = consumer.poll(10);//一次拉取10条数据
                for (ConsumerRecord<String, String> record : records) {
                    String key = record.key();
                    String value = record.value();
                    System.out.printf("offset = %d, key = %s, value = %s", record.offset(), key ,value);
                    collector.emit(new Values(value));//发射数据
                }
                Thread.sleep(1000*1);//每隔一秒拉取一次
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            consumer.close();
        }

    }

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {
        // TODO Auto-generated method stub
        declarer.declare(new Fields("sentence"));

    }

}

3.HelloWorldBolt.java源码如下:

package com.yg.storm.bolts;

import java.util.Map;

import org.apache.storm.task.OutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.topology.base.BaseRichBolt;
import org.apache.storm.tuple.Tuple;

public class HelloWorldBolt extends BaseRichBolt{

    /**
     * 功能：就收到spout发送的数据，打印并统计hello world的数量
     * 实现：打印，创建计数变量用于统计hello world
     */
    private static final long serialVersionUID = -5061906223048521415L;
    private int myCount = 0;//计数变量，不能在execute函数中初始化
    private TopologyContext context;//上下文变量
    private OutputCollector collector;

    //相当于spout中的open
    @Override
    public void prepare(Map stormConf,
            TopologyContext context,
            OutputCollector collector) {
        this.context = context;
        this.collector = collector;
    }

    //相当于spout中的nextTuple
    @Override
    public void execute(Tuple input) {
        //拿到数据，用字段名取出
        String text = input.getStringByField("sentence");
        System.out.println("One tuple gets in: " + context.getThisTaskId() + text);
        if ("Hello World".equals(text)){
            myCount++;
            System.out.println("Found a Hello World! My count is now:" + myCount);
        }
        collector.ack(input);//处理完成要通知Storm
//        collector.fail(input);//处理失败要通知Storm    

    }

    @Override
    public void declareOutputFields(OutputFieldsDeclarer declarer) {

    }
}

4.KafkaHelloWorldTopology.java源码如下:

package com.yg.storm.kafka.topologies;

import org.apache.storm.Config;
import org.apache.storm.LocalCluster;
import org.apache.storm.StormSubmitter;
import org.apache.storm.kafka.BrokerHosts;
import org.apache.storm.kafka.KafkaSpout;
import org.apache.storm.kafka.SpoutConfig;
import org.apache.storm.kafka.ZkHosts;
import org.apache.storm.spout.SchemeAsMultiScheme;
import org.apache.storm.topology.TopologyBuilder;
import org.apache.storm.utils.Utils;

import com.yg.storm.bolts.HelloWorldBolt;

public class KafkaHelloWorldTopology {

    //可以向main函数传入一个参数作为集群模式下Topology的名字，如果不传入任何参数则使用本地模式
    public static void main(String[] args) {

            final String brokerZkStr = "hadoop211:2181,hadoop212:2181,hadoop213:2181";
            final String topic  = "myTopic";

            BrokerHosts brokerHosts = new ZkHosts(brokerZkStr);

//          //使用KafkaConfig
//          KafkaConfig kafkaConfig = new KafkaConfig(
//                  brokerHosts,
//                  topic
//                  );

            //使用SpoutConfig，它继承自KafkaConfig，延伸了几个功能配置
            SpoutConfig spoutConfig = new SpoutConfig(
                    brokerHosts, //storm要连接的kafka的对应的zk列表
                    topic, //storm要消费的kafka的topic
                    "/HWTopo", //storm在kafka消费的过程中需要在zk中设置一个工作目录
                    "kafkaspout");  //storm在kafka中消费过程中生产一个标识ID

            //指定自定义的scheme
            spoutConfig.scheme = new SchemeAsMultiScheme(new MessageScheme());

            TopologyBuilder builder = new TopologyBuilder();
            builder.setSpout("spout", new KafkaSpout(spoutConfig));
            builder.setBolt("bolt1", new HelloWorldBolt()).shuffleGrouping("spout");

            Config conf = new Config();
//          Map<String, String> map = new HashMap<String, String>();
//
//          map.put("metadata.broker.list", "hadoop211:9092,hadoop212:9092,hadoop213:9092");
//          map.put("serializer.class", "kafka.serializer.StringEncoder");
//          conf.put("kafka.broker.properties", map);
//          conf.put("topic", topic);

            if(args != null && args.length > 0) {
                //提交到集群运行
                try {
                    StormSubmitter.submitTopology(args[0], conf, builder.createTopology());
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else {
                //本地模式运行
                LocalCluster cluster = new LocalCluster();
                cluster.submitTopology("SchemeTopo", conf, builder.createTopology());
                Utils.sleep(1000000);
                cluster.killTopology("SchemeTopo");
                cluster.shutdown();
            }

        }

}

5.自定义schema类MessageScheme.java源码如下:

package com.yg.storm.kafka.topologies;

import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.util.List;

import org.apache.storm.spout.Scheme;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Values;

//编写storm消费kafka的逻辑
/*
 * MultiScheme is an interface that dictates how the ByteBuffer consumed
 * from Kafka gets transformed into a storm tuple.
 * It also controls the naming of your output field.
 *
 * The default RawMultiScheme just takes the ByteBuffer and returns a tuple
 * with the ByteBuffer converted to a byte[].
 * The name of the outputField is "bytes".
 * There are alternative implementations like SchemeAsMultiScheme and
 * KeyValueSchemeAsMultiScheme which can convert the ByteBuffer to String.
 *
 */

public class MessageScheme implements Scheme {

    private static final long serialVersionUID = 1033379821285531859L;

    @Override
    public List<Object> deserialize(ByteBuffer buffer) {

        try {
            Charset charset = Charset.forName("UTF-8");
            CharsetDecoder decoder = charset.newDecoder();
            CharBuffer charBuffer = decoder.decode(buffer.asReadOnlyBuffer());

            String sentence = charBuffer.toString();
            return new Values(sentence);

        } catch (Exception e) {
            System.out.println(e);
            return null;
        }
    }

    @Override
    public Fields getOutputFields() {
        return new Fields("sentence");
    }

}

直接本地运行KafkaHelloWorldTopology类即可.