Kafka發布訂閱消息

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

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服務器ip
        props.put("acks", "all");//所有follower都響應了才認為消息提交成功，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將試圖批處理消息記錄，以減少請求次數.默認的批量處理消息字節數
        //batch.size當批量的數據大小達到設定值后，就會立即發送，不顧下面的linger.ms
        props.put("linger.ms", 1);//延遲1ms發送，這項設置將通過增加小的延遲來完成--即，不是立即發送一條記錄，producer將會等待給定的延遲時間以允許其他消息記錄發送，這些消息記錄可以批量處理
        props.put("buffer.memory", 33554432);//producer可以用來緩存數據的內存大小。
        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

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是服務器集群的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();
                }
            }
 
        }
}