Kafka入门实例

<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.test</groupId>
	<artifactId>Kafka-Demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>

	<dependencies>
		<dependency>
			<groupId>org.apache.kafka</groupId>
			<artifactId>kafka_2.10</artifactId>
			<version>0.9.0.0</version>
		</dependency>

		<dependency>
			<groupId>io.appium</groupId>
			<artifactId>java-client</artifactId>
			<version>6.0.0-BETA5</version>
		</dependency>

		<dependency>
			<groupId>com.alibaba</groupId>
			<artifactId>fastjson</artifactId>
			<version>1.2.4</version>
		</dependency>

	</dependencies>
</project>  

2、生产者

package com;

import java.util.Properties;

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



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

	private KafkaProducer() {  
		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 KafkaProducer().produce();  
	}  
}

 右键：run as java application,执行前需要启动Zookeeper、kafka，具体操作详见

 http://zhangwenlongchina.iteye.com/admin/blogs/2420493

 运行结果：

3、消费者

package com;

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;  


public class KafkaConsumer {  

	private final ConsumerConnector consumer;  

	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(KafkaProducer.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(KafkaProducer.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();  
	}  
}  

 运行结果：