java 實現kafka訊息生產者和消費者
阿新 • • 發佈:2018-12-23
一、概述
kafka原理這東西就不再贅述了,除了官網網上也是能找到一大堆,直接上程式碼,這裡實現的基本需求是 producer類利用for迴圈來產生訊息,然後consumer類來消費這些訊息,我的正確執行環境是:
centos-6.5
kafka-2.10_0.10
scala-2.10.4
二、程式碼
生產者:
package com.unisk.bigdata.kafka;
import java.util.Properties;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache .kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;
public class MyProducer {
public static void main(String[] args) {
Properties props = new Properties();
props.put("bootstrap.servers", "master:9092");
props.put("acks", "all");
props.put("retries" , 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
props.put("buffer.memory", 33554432);
props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
Producer<String, String> producer = null;
try {
producer = new KafkaProducer<>(props);
for (int i = 0; i < 100; i++) {
String msg = "Message " + i;
producer.send(new ProducerRecord<String, String>("HelloKafka", msg));
System.out.println("Sent:" + msg);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
producer.close();
}
}
}
消費者
package com.unisk.bigdata.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 MyConsumer {
public static void main(String[] args) {
Properties props = new Properties();
props.put("bootstrap.servers", "master:9092");
props.put("group.id", "group-1");
props.put("enable.auto.commit", "true");
props.put("auto.commit.interval.ms", "1000");
props.put("auto.offset.reset", "earliest");
props.put("session.timeout.ms", "30000");
props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<>(props);
kafkaConsumer.subscribe(Arrays.asList("HelloKafka"));
while (true) {
ConsumerRecords<String, String> records = kafkaConsumer.poll(100);
for (ConsumerRecord<String, String> record : records) {
System.out.printf("offset = %d, value = %s", record.offset(), record.value());
System.out.println();
}
}
}
}
三、結果展示
執行生產者之後
Sent:Message 0
Sent:Message 1
Sent:Message 2
Sent:Message 3
Sent:Message 4
Sent:Message 5
Sent:Message 6
Sent:Message 7
……
執行消費者後
offset = 67, value = Message 2
offset = 68, value = Message 5
offset = 69, value = Message 8
offset = 70, value = Message 11
offset = 71, value = Message 14
offset = 72, value = Message 17
offset = 73, value = Message 20
offset = 74, value = Message 23
offset = 75, value = Message 26
offset = 76, value = Message 29
……