Java實現Kafka讀寫筆記

1.POM.XML

<dependencies>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>0.8.2.1</version>
        </dependency>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka_2.11</artifactId>
            <version>0.8.2.1</version>
        </dependency>
    </dependencies>

2.生成者

import kafka.javaapi.producer.Producer;
import kafka.producer.KeyedMessage;
import kafka.producer.ProducerConfig;

import java.util.Properties;

public class RunKafkaProduce {

    private final Producer<String, String> producer;
    public final static String TOPIC = "logstest";

    private RunKafkaProduce(){

        Properties props = new Properties();

        // 此處配置的是kafka的broker地址:埠列表
        props.put("metadata.broker.list", "172.19.4.230:9092");

        //配置value的序列化類
        props.put("serializer.class", "kafka.serializer.StringEncoder");

        //配置key的序列化類
        props.put("key.serializer.class", "kafka.serializer.StringEncoder");

        //request.required.acks
        //0, which means that the producer never waits for an acknowledgement from the broker (the same behavior as 0.7). This option provides the lowest latency but the weakest durability guarantees (some data will be lost when a server fails).
        //1, which means that the producer gets an acknowledgement after the leader replica has received the data. This option provides better durability as the client waits until the server acknowledges the request as successful (only messages that were written to the now-dead leader but not yet replicated will be lost).
        //-1, which means that the producer gets an acknowledgement after all in-sync replicas have received the data. This option provides the best durability, we guarantee that no messages will be lost as long as at least one in sync replica remains.
        props.put("request.required.acks","-1");

        producer = new Producer<String, String>(new ProducerConfig(props));
    }

    void produce() {
        int messageNo = 1;
        final int COUNT = 101;

        int messageCount = 0;
        while (messageNo < COUNT) {
            String key = String.valueOf(messageNo);
            String data = "Hello kafka message :" + key;
            producer.send(new KeyedMessage<String, String>(TOPIC, key ,data));
            System.out.println(data);
            messageNo ++;
            messageCount++;
        }

        System.out.println("Producer端一共產生了" + messageCount + "條訊息！");
    }

    public static void main( String[] args )
    {
        new RunKafkaProduce().produce();
    }

}

3.消費著

import kafka.consumer.ConsumerConfig;
import kafka.consumer.ConsumerIterator;
import kafka.consumer.KafkaStream;
import kafka.javaapi.consumer.ConsumerConnector;
import kafka.serializer.StringDecoder;
import kafka.utils.VerifiableProperties;
import org.apache.kafka.clients.producer.KafkaProducer;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;

/**
 * ////////////////////////////////////////////////////////////////////
 * //                          _ooOoo_                               //
 * //                         o8888888o                              //
 * //                         88" . "88                              //
 * //                         (| ^_^ |)                              //
 * //                         O\  =  /O                              //
 * //                      ____/`---'\____                           //
 * //                    .'  \\|     |//  `.                         //
 * //                   /  \\|||  :  |||//  \                        //
 * //                  /  _||||| -:- |||||-  \                       //
 * //                  |   | \\\  -  /// |   |                       //
 * //                  | \_|  ''\---/''  |   |                       //
 * //                  \  .-\__  `-`  ___/-. /                       //
 * //                ___`. .'  /--.--\  `. . ___                     //
 * //              ."" '<  `.___\_<|>_/___.'  >'"".                  //
 * //            | | :  `- \`.;`\ _ /`;.`/ - ` : | |                 //
 * //            \  \ `-.   \_ __\ /__ _/   .-` /  /                 //
 * //      ========`-.____`-.___\_____/___.-`____.-'========         //
 * //                           `=---='                              //
 * //      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^        //
 * //         佛祖保佑    			再無Bug				              //
 * ////////////////////////////////////////////////////////////////////
 * User:Klin
 * Date:2017/4/18 0018
 */
public class RunKafkaConsumer {

    private final ConsumerConnector consumer;

    private final static  String TOPIC="logstest";

    private RunKafkaConsumer(){
        Properties props=new Properties();
        //zookeeper
        props.put("zookeeper.connect","zero230:2181");
        //topic
        props.put("group.id","logstest");

        //Zookeeper 超時
        props.put("zookeeper.session.timeout.ms", "4000");
        props.put("zookeeper.sync.time.ms", "200");
        props.put("auto.commit.interval.ms", "1000");
        props.put("auto.offset.reset", "smallest");


        props.put("serializer.class", "kafka.serializer.StringEncoder");

        ConsumerConfig config=new ConsumerConfig(props);

        consumer= kafka.consumer.Consumer.createJavaConsumerConnector(config);
    }


    void consume(){
        Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
        topicCountMap.put(TOPIC, new Integer(1));

        StringDecoder keyDecoder = new StringDecoder(new VerifiableProperties());
        StringDecoder valueDecoder = new StringDecoder(new VerifiableProperties());

        Map<String, List<KafkaStream<String, String>>> consumerMap =
                consumer.createMessageStreams(topicCountMap,keyDecoder,valueDecoder);
        KafkaStream<String, String> stream = consumerMap.get(TOPIC).get(0);
        ConsumerIterator<String, String> it = stream.iterator();

        int messageCount = 0;
        while (it.hasNext()){
            System.out.println(it.next().message());
            messageCount++;
            if(messageCount == 100){
                System.out.println("Consumer端一共消費了" + messageCount + "條訊息！");
            }
        }
    }

    public static void main(String[] args) {
        new RunKafkaConsumer().consume();
    }

}