ConsumerExample.java

package com.digipepper.test.kafka.consumer;

import kafka.consumer.ConsumerConfig;
import kafka.consumer.ConsumerIterator;
import kafka.consumer.KafkaStream;
import kafka.message.Message;
import kafka.javaapi.consumer.ConsumerConnector;
import kafka.api.OffsetRequest;

import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ConsumerExample {
    private static ConsumerConnector consumer;

    public static void main(String[] args) {
        String zooKeeper = args[0];
        String groupId = args[1];
        String topic = args[2];
        int threads = Integer.parseInt(args[3]);

        // Create the connection to the cluster
        consumer = kafka.consumer.Consumer.createJavaConsumerConnector(
                createConsumerConfig( zooKeeper, groupId));

        // create 4 partitions of the stream for topic, to allow 4 threads to consume
        Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
        topicCountMap.put(topic, threads);
        Map<String, List<KafkaStream<Message>>> consumerMap = consumer.createMessageStreams(topicCountMap);
        List<KafkaStream<Message>> streams = consumerMap.get(topic);

        // create list of 4 threads to consume from each of the partitions
        ExecutorService executor = Executors.newFixedThreadPool(4);

        // consume the messages in the threads
        for (final KafkaStream<Message> stream: streams) {
            executor.submit(new Runnable() {
                public void run() {
                        ConsumerIterator<Message> it = stream.iterator();
                        while (it.hasNext())
                            System.out.println("Msg: " + getMessage(it.next().message()));
                    }
                }
            );
        }
    }


  private static ConsumerConfig createConsumerConfig(String a_zookeeper, String a_groupId) {

		Properties props = new Properties();
		props.put("zk.connect", a_zookeeper);
		props.put("groupid", a_groupId);
		props.put("zookeeper.session.timeout.ms", "400");
		props.put("zookeeper.sync.time.ms", "200");
		props.put("auto.commit.interval.ms", "1000");
		props.put("autooffset.reset", OffsetRequest.LargestTimeString());
		System.out.println("LargestTimeString:"+OffsetRequest.LargestTimeString());
		
		return new ConsumerConfig(props);
	}

	private static String getMessage(Message message) {
		ByteBuffer buffer = message.payload();
		byte [] bytes = new byte[buffer.remaining()];
		buffer.get(bytes);
		return new String(bytes);
	}
}

Kafkaのバージョンはv0.7.2でやってます。

なお、複数のGroup名を使ってしまうと、Group名Aで読んだ位置(読み進んだ位置)と、Gorup名Bで読んだ位置が異なってしまい、AがBより進んだ後にBが接続すると、Bにはその差分が、接続時に流れ込んでくることになります。

コメント書いたらメールとか飛ぶんですかね？