Kafka之生产者消费者示例

Posted 2021-02-09 zengnansheng

本例以kafka2.10_0.10.0.0为例，不同版本的kafka Java api有些区别!

 

增加maven依赖

<dependency>  
    <groupId>org.apache.kafka</groupId>  
    <artifactId>kafka_2.10</artifactId>  
    <version>0.10.0.0</version>  
</dependency>

生产者

package com.zns.kafka;

import java.util.Properties;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.serialization.StringSerializer;

public class KafkaProducerTest {
    public static String topicName = "test";

    public static void main(String[] args) {
        Properties props = new Properties();
        props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "127.0.0.1:9092");// 9092是kafka默认端口
        props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());

        KafkaProducer<String, String> producer = new KafkaProducer<String, String>(props);
        for (int i = 1; i <= 10; i++) {
            ProducerRecord<String, String> message = new ProducerRecord<String, String>(topicName, "hello world " + i);
            producer.send(message);
            producer.flush();
        }
    }
}

 

 

消费者

package com.zns.kafka;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.common.serialization.StringSerializer;
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 KafkaConsumerTest {
    public static String topicName = "test";

    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("zookeeper.connect", "127.0.0.1:2181");// 2181是zookeeper默认端口
        props.put("group.id", "test-group");
        props.put("zookeeper.session.timeout.ms", "100000");
        props.put("zookeeper.sync.time.ms", "200");
        props.put("auto.commit.interval.ms", "1000");
        props.put("auto.offset.reset", "smallest");
        props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());

        ConsumerConfig config = new ConsumerConfig(props);
        ConsumerConnector consumer = kafka.consumer.Consumer.createJavaConsumerConnector(config);

        Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
        topicCountMap.put(topicName, 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(topicName).get(0);
        ConsumerIterator<String, String> it = stream.iterator();
        while (it.hasNext()) {
            System.out.println("收到消息：" + it.next().message());
        }
    }
}

 

 

确保启动运行了zookeeper和kafka

先后启动运行生产者和消费者，可以看到消费者端接收到了消息...