上篇文章中我们搭建了kafka的server,并能够使用Kafka的命令行工具创建topic,发送和接收消息。
以下我们来搭建kafka的开发环境。
加入依赖
搭建开发环境须要引入kafka的jar包,一种方式是将Kafka安装包中lib下的jar包增加到项目的classpath中,这样的比較简单了。
只是我们使用还有一种更加流行的方式:使用maven管理jar包依赖。
创建好maven项目后,在pom.xml中加入下面依赖:
<dependency> <groupId>org.apache.kafka</groupId> <artifactId>kafka_2.10</artifactId> <version>0.8.2.2</version> </dependency>
加入依赖后假设有两个jar包的依赖找不到。点击这里下载这两个jar包,解压后你有两种选择,第一种是使用mvn的install命令将jar包安装到本地仓库,还有一种是直接将解压后的目录复制到mvn本地仓库的com目录下,比方我的本地仓库是d:mvn,完毕后我的目录结构是这种:
配置程序
更新更全的API编程实例点这里:http://blog.csdn.net/honglei915/article/details/37697655
首先是一个充当配置文件作用的接口,配置了Kafka的各种连接參数:
package com.sohu.kafkademon; public interface KafkaProperties { final static String zkConnect = "10.22.10.139:2181"; final static String groupId = "group1"; final static String topic = "topic1"; final static String kafkaServerURL = "10.22.10.139"; final static int kafkaServerPort = 9092; final static int kafkaProducerBufferSize = 64 * 1024; final static int connectionTimeOut = 20000; final static int reconnectInterval = 10000; final static String topic2 = "topic2"; final static String topic3 = "topic3"; final static String clientId = "SimpleConsumerDemoClient"; }
producer
package com.sohu.kafkademon; import java.util.Properties; import kafka.producer.KeyedMessage; import kafka.producer.ProducerConfig; /** * @author leicui bourne_cui@163.com */ public class KafkaProducer extends Thread { private final kafka.javaapi.producer.Producer<Integer, String> producer; private final String topic; private final Properties props = new Properties(); public KafkaProducer(String topic) { props.put("serializer.class", "kafka.serializer.StringEncoder"); props.put("metadata.broker.list", "10.22.10.139:9092"); producer = new kafka.javaapi.producer.Producer<Integer, String>(new ProducerConfig(props)); this.topic = topic; } @Override public void run() { int messageNo = 1; while (true) { String messageStr = new String("Message_" + messageNo); System.out.println("Send:" + messageStr); producer.send(new KeyedMessage<Integer, String>(topic, messageStr)); messageNo++; try { sleep(3000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
consumer
package com.sohu.kafkademon; 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; /** * @author leicui bourne_cui@163.com */ public class KafkaConsumer extends Thread { private final ConsumerConnector consumer; private final String topic; public KafkaConsumer(String topic) { consumer = kafka.consumer.Consumer.createJavaConsumerConnector( createConsumerConfig()); this.topic = topic; } private static ConsumerConfig createConsumerConfig() { Properties props = new Properties(); props.put("zookeeper.connect", KafkaProperties.zkConnect); props.put("group.id", KafkaProperties.groupId); props.put("zookeeper.session.timeout.ms", "40000"); props.put("zookeeper.sync.time.ms", "200"); props.put("auto.commit.interval.ms", "1000"); return new ConsumerConfig(props); } @Override public void run() { Map<String, Integer> topicCountMap = new HashMap<String, Integer>(); topicCountMap.put(topic, new Integer(1)); Map<String, List<KafkaStream<byte[], byte[]>>> consumerMap = consumer.createMessageStreams(topicCountMap); KafkaStream<byte[], byte[]> stream = consumerMap.get(topic).get(0); ConsumerIterator<byte[], byte[]> it = stream.iterator(); while (it.hasNext()) { System.out.println("receive:" + new String(it.next().message())); try { sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); } } } }
简单的发送接收
执行以下这个程序,就能够进行简单的发送接收消息了:
package com.sohu.kafkademon; /** * @author leicui bourne_cui@163.com */ public class KafkaConsumerProducerDemo { public static void main(String[] args) { KafkaProducer producerThread = new KafkaProducer(KafkaProperties.topic); producerThread.start(); KafkaConsumer consumerThread = new KafkaConsumer(KafkaProperties.topic); consumerThread.start(); } }
高级别的consumer
以下是比較负载的发送接收的程序:
package com.sohu.kafkademon; 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; /** * @author leicui bourne_cui@163.com */ public class KafkaConsumer extends Thread { private final ConsumerConnector consumer; private final String topic; public KafkaConsumer(String topic) { consumer = kafka.consumer.Consumer.createJavaConsumerConnector( createConsumerConfig()); this.topic = topic; } private static ConsumerConfig createConsumerConfig() { Properties props = new Properties(); props.put("zookeeper.connect", KafkaProperties.zkConnect); props.put("group.id", KafkaProperties.groupId); props.put("zookeeper.session.timeout.ms", "40000"); props.put("zookeeper.sync.time.ms", "200"); props.put("auto.commit.interval.ms", "1000"); return new ConsumerConfig(props); } @Override public void run() { Map<String, Integer> topicCountMap = new HashMap<String, Integer>(); topicCountMap.put(topic, new Integer(1)); Map<String, List<KafkaStream<byte[], byte[]>>> consumerMap = consumer.createMessageStreams(topicCountMap); KafkaStream<byte[], byte[]> stream = consumerMap.get(topic).get(0); ConsumerIterator<byte[], byte[]> it = stream.iterator(); while (it.hasNext()) { System.out.println("receive:" + new String(it.next().message())); try { sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); } } } }