Window平台实现Kafka的生产者消费者Java版本示例

本文Window平台实现Kafka的生产者消费者Java版本示例，前提是已经安装好Kafka环境并启动zkserver和kafka

1)消费者代码实现（特别注意的是：文件命名为 KafkaConsumer.java  与消费者类名相同）

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

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 com.lin.demo.producer.KafkaProducer;


public class KafkaConsumer{

    private final ConsumerConnector consumer;
    public final static String TOPIC = "linlin";

    private KafkaConsumer() {
        Properties props = new Properties();
        // zookeeper 配置
        props.put("zookeeper.connect", "127.0.0.1:2181");

        // group 代表一个消费组
        props.put("group.id", "lingroup");

        // zk连接超时
        props.put("zookeeper.session.timeout.ms", "4000");
        props.put("zookeeper.sync.time.ms", "200");
        props.put("rebalance.max.retries", "5");
        props.put("rebalance.backoff.ms", "1200");


        props.put("auto.commit.interval.ms", "1000");
        props.put("auto.offset.reset", "smallest");
        // 序列化类
        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();
        while (it.hasNext())
            System.out.println("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<" + it.next().message() + "<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<");
    }

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

2）生产者代码实现（特别注意的是：文件命名为 KafkaProducerT.java  与生产者类名相同）

//package com.lin.demo.producer;

import java.util.Properties;

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

public class KafkaProducerT{
    private final Producer<String, String> producer;
    public final static String TOPIC = "linlin";

    private KafkaProducerT() {
        Properties props = new Properties();
        // 此处配置的是kafka的端口
        props.put("metadata.broker.list", "127.0.0.1:9092");
        props.put("zk.connect", "127.0.0.1:2181");

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

        props.put("request.required.acks", "-1");

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

    void produce() {
        int messageNo = 1000;
        final int COUNT = 10000;

        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++;
        }
    }

    public static void main(String[] args) {
        new KafkaProducerT().produce();
        //System.out.println("你好 KafkaProducer");
    }
}

3）编译并运行
将生产者（KafkaProducerT.java）与消费者（KafkaConsumer.java ）代码放在C:\kafka_2.12-1.0.0 下，这样放置程序文件方便引用
a)编译和运行消费者
C:\kafka_2.12-1.0.0>javac KafkaConsumer.java -cp ./libs/*
C:\kafka_2.12-1.0.0>java -cp .;./libs/*  KafkaConsumer

b)编译生产者
C:\kafka_2.12-1.0.0>javac KafkaProducerT.java -cp ./libs/*
C:\kafka_2.12-1.0.0>java -cp .;./libs/* KafkaProducerT