Kafka多线程生产消费

一、kafka生产者

       kafka目前在0.9版本后采用java版本实现，生产者KafkaProducer是线程安全对象，所以我们建议KafkaProducer采用单例模式,多个线程共享一个实例

    

package com.kafka.singleton;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import java.util.Random;

import org.apache.kafka.clients.producer.Callback;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.clients.producer.RecordMetadata;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public final class KafkaProducerSingleton {

	private static final Logger LOGGER = LoggerFactory
			.getLogger(KafkaProducerSingleton.class);

	private static KafkaProducer<String, String> kafkaProducer;

	private Random random = new Random();

	private String topic;

	private int retry;

	private KafkaProducerSingleton() {

	}
	

	/**
	 * 静态内部类
	 * 
	 * @author tanjie
	 *
	 */
	private static class LazyHandler {

		private static final KafkaProducerSingleton instance = new KafkaProducerSingleton();
	}

	/**
	 * 单例模式,kafkaProducer是线程安全的,可以多线程共享一个实例
	 * 
	 * @return
	 */
	public static final KafkaProducerSingleton getInstance() {
		return LazyHandler.instance;
	}

	/**
	 * kafka生产者进行初始化
	 * 
	 * @return KafkaProducer
	 */
	public void init(String topic,int retry) {
		this.topic = topic;
	    this.retry = retry;
		if (null == kafkaProducer) {
			Properties props = new Properties();
			InputStream inStream = null;
			try {
				inStream = this.getClass().getClassLoader()
						.getResourceAsStream("kafka.properties");
				props.load(inStream);
				kafkaProducer = new KafkaProducer<String, String>(props);
			} catch (IOException e) {
				LOGGER.error("kafkaProducer初始化失败:" + e.getMessage(), e);
			} finally {
				if (null != inStream) {
					try {
						inStream.close();
					} catch (IOException e) {
						LOGGER.error("kafkaProducer初始化失败:" + e.getMessage(), e);
					}
				}
			}
		}
	}

	/**
	 * 通过kafkaProducer发送消息
	 * 
	 * @param topic
	 *            消息接收主题
	 * @param p