上篇文章中我们搭建了kafka的服务器,并可以使用Kafka的命令行工具创建topic,发送和接收消息。下面我们来搭建kafka的开发环境。
添加依赖
搭建开发环境需要引入kafka的jar包,一种方式是将Kafka安装包中lib下的jar包加入到项目的classpath中,这种比较简单了。不过我们使用另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中添加以下依赖:
- <dependency>
- <groupId> org.apache.kafka</groupId >
- <artifactId> kafka_2.10</artifactId >
- <version> 0.8.0</ version>
- </dependency>
添加依赖后你会发现有两个jar包的依赖找不到。没关系我都帮你想好了,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,另一种是直接将解压后的文件夹拷贝到mvn本地仓库的com文件夹下,比如我的本地仓库是d:mvn,完成后我的目录结构是这样的:
配置程序
首先是一个充当配置文件作用的接口,配置了Kafka的各种连接参数:
- 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
运行下面这个程序,就可以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
下面是比较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();
- }
- }
- }
- }