Kafka 生产者消费者java示例代码详解编程语言

[Java]代码    

package com.cz.producer; 
 
/** 
 * Created by Administrator on 2015/10/10. 
 */ 
import java.util.Properties; 
 
import kafka.javaapi.producer.Producer; 
import kafka.producer.KeyedMessage; 
import kafka.producer.ProducerConfig; 
 
/** 
 * Hello world! 
 * 
 */ 
public class KafkaProducer 
{ 
    private final Producer<String, String> producer; 
    public final static String TOPIC = "com.cz.service.map.entryCity"; 
 
    private KafkaProducer(){ 
        Properties props = new Properties(); 
        // 
        props.put("metadata.broker.list", "192.168.0.208:9092"); 
 
        //����value������� 
        props.put("serializer.class", "kafka.serializer.StringEncoder"); 
        //����key������� 
        props.put("key.serializer.class", "kafka.serializer.StringEncoder"); 
 
        //request.required.acks 
        //0, which means that the producer never waits for an acknowledgement from the broker (the same behavior as 0.7). This option provides the lowest latency but the weakest durability guarantees (some data will be lost when a server fails). 
        //1, which means that the producer gets an acknowledgement after the leader replica has received the data. This option provides better durability as the client waits until the server acknowledges the request as successful (only messages that were written to the now-dead leader but not yet replicated will be lost). 
        //-1, which means that the producer gets an acknowledgement after all in-sync replicas have received the data. This option provides the best durability, we guarantee that no messages will be lost as long as at least one in sync replica remains. 
        props.put("request.required.acks","-1"); 
 
        producer = new Producer<String, String>(new ProducerConfig(props)); 
    } 
 
    void produce() { 
        int messageNo = 2000; 
        final int COUNT = 2100; 
 
        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(); 
    } 
}

[Java]代码    

package com.cz.producer; 
 
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; 
 
/** 
 * Created by Administrator on 2015/10/10. 
 */ 
public class KafkaConsumer { 
 
    private final ConsumerConnector consumer; 
 
    private KafkaConsumer() { 
        Properties props = new Properties(); 
        //zookeeper 配置 
        props.put("zookeeper.connect", "192.168.0.208:2181"); 
 
        //group 代表一个消费组 
        props.put("group.id", "jd-group"); 
 
        // 连接zk的session超时时间 
        props.put("zookeeper.session.timeout.ms", "4000"); 
        props.put("zookeeper.sync.time.ms", "200");//zk follower落后于zk leader的最长时间        props.put("auto.commit.interval.ms", "1000");//往zookeeper上写offset的频率        props.put("auto.offset.reset", "smallest");//如果offset出了返回，则 smallest: 自动设置reset到最小的offset. largest : 自动设置offset到最大的offset. 其它值不允许，会抛出异常         
        //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(); 
    } 
}