之前寫了一篇關於kafka叢集搭建的點選開啟連結。想了解的可以看下。

今天這個實現是和前面叢集對應的。使用的是新版的API。屬性如果想定製自己的，需要到官方網址上面去檢視一下對應的值。

推介大家多去看看官方的介紹和demo。網上有些翻譯過來的例子並不完善，最好是知己知彼，才能百戰不殆

maven：

	<dependency>
    		<groupId>org.apache.kafka</groupId>
    		<artifactId>kafka-clients</artifactId>
    		<version>0.11.0.0</version>
    	</dependency>
   	    <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-streams</artifactId>
            <version>0.11.0.0</version>
    	</dependency>
 

生產者Producer：

package com.roncoo.example.kafka;

import java.util.Properties;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

public class ProducerDemo {

    private final KafkaProducer<String, String> producer;

    public final static String TOPIC = "test5";

    private ProducerDemo() {
        Properties props = new Properties();
        props.put("bootstrap.servers", "xxx:9092,1xxx:9092,xxx:9092");//xxx伺服器ip
        props.put("acks", "all");//所有follower都響應了才認為訊息提交成功，即"committed"
        props.put("retries", 0);//retries = MAX 無限重試，直到你意識到出現了問題:)
        props.put("batch.size", 16384);//producer將試圖批處理訊息記錄，以減少請求次數.預設的批量處理訊息位元組數
        //batch.size當批量的資料大小達到設定值後，就會立即傳送，不顧下面的linger.ms
        props.put("linger.ms", 1);//延遲1ms傳送，這項設定將通過增加小的延遲來完成--即，不是立即傳送一條記錄，producer將會等待給定的延遲時間以允許其他訊息記錄傳送，這些訊息記錄可以批量處理
        props.put("buffer.memory", 33554432);//producer可以用來快取資料的記憶體大小。
        props.put("key.serializer",
                "org.apache.kafka.common.serialization.IntegerSerializer");
        props.put("value.serializer",
              "org.apache.kafka.common.serialization.StringSerializer");

        producer = new KafkaProducer<String, String>(props);
    }

    public void produce() {
        int messageNo = 1;
        final int COUNT = 5;

        while(messageNo < COUNT) {
            String key = String.valueOf(messageNo);
            String data = String.format("hello KafkaProducer message %s from hubo 06291018 ", key);
            
            try {
                producer.send(new ProducerRecord<String, String>(TOPIC, data));
            } catch (Exception e) {
                e.printStackTrace();
            }

            messageNo++;
        }
        
        producer.close();
    }

    public static void main(String[] args) {
        new ProducerDemo().produce();
    }
}
 

消費者Consumer:

package com.roncoo.example.kafka;
import java.util.Arrays;
import java.util.Properties;

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;


public class UserKafkaConsumer extends Thread {

        public static void main(String[] args){
            Properties properties = new Properties();
            properties.put("bootstrap.servers", "xxx:9092,xxx:9092,xxx:9092");//xxx是伺服器叢集的ip
            properties.put("group.id", "jd-group");
            properties.put("enable.auto.commit", "true");
            properties.put("auto.commit.interval.ms", "1000");
            properties.put("auto.offset.reset", "latest");
            properties.put("session.timeout.ms", "30000");
            properties.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
            properties.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

            KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<>(properties);
            kafkaConsumer.subscribe(Arrays.asList("test5"));
            while (true) {
                ConsumerRecords<String, String> records = kafkaConsumer.poll(100);
                for (ConsumerRecord<String, String> record : records) {
                    System.out.println("-----------------");
                    System.out.printf("offset = %d, value = %s", record.offset(), record.value());
                    System.out.println();
                }
            }

        }
}