前提:需要Kafka集群。
创建一个简单的gradle项目
build.gradle配置信息
buildscript {
repositories {
maven {
url 'http://maven.aliyun.com/nexus/content/groups/public/' }
maven{
url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
}
}
plugins {
id 'java'
}
version 'unspecified'
sourceCompatibility = 1.8
repositories {
mavenCentral()
}
dependencies {
testCompile group: 'junit', name: 'junit', version: '4.12'
compile group: 'org.apache.kafka', name: 'kafka_2.12', version: '2.6.0'
compile group: 'org.apache.kafka', name: 'kafka-clients', version: '2.6.0'
}
allprojects {
repositories {
maven {
url 'http://maven.aliyun.com/nexus/content/groups/public/' }
maven{
url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
}
}
创建生产者类
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.serialization.StringDeserializer;
import java.util.Properties;
import java.util.Random;
public class MsgKafkaProducer extends Thread {
private final KafkaProducer<Integer, String> producer;
private final String topic;
public MsgKafkaProducer(String topic) {
Properties props = new Properties();
props.put("metadata.broker.list", "192.168.88.62:9092");
props.put("bootstrap.servers", "192.168.88.62:9092");
props.put("retries", 0);
props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
producer = new KafkaProducer<>(props);
this.topic = topic;
}
@Override
public void run() {
int messageNo = 1;
Random random = new Random();
for (int i = 0; i < 1000; i++) {
String messageStr = "Message" + random.nextInt(10000) + " " + messageNo;
System.out.println("Send:" + messageStr);
producer.send(new ProducerRecord<>(topic, messageStr));
messageNo++;
}
}
public static void main(String[] args) {
MsgKafkaProducer producerThread = new MsgKafkaProducer("kafka_test");
producerThread.start();
}
}
创建消费者类
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.common.serialization.StringDeserializer;
import java.util.Collections;
import java.util.Properties;
public class MsgKafkaConsumer implements Runnable {
private final KafkaConsumer<String, String> consumer;
private static final String GROUP_ID = "groupA";
public MsgKafkaConsumer(String topicName) {
Properties props = new Properties();
props.put("bootstrap.servers", "192.168.88.62:9092");
props.put("group.id", GROUP_ID);
props.put("enable.auto.commit", "true");
props.put("auto.commit.interval.ms", "1000");
props.put("session.timeout.ms", "30000");
props.put("auto.offset.reset", "earliest");
props.put("key.deserializer", StringDeserializer.class.getName());
props.put("value.deserializer", StringDeserializer.class.getName());
this.consumer = new KafkaConsumer<String, String>(props);
this.consumer.subscribe(Collections.singletonList(topicName));
}
@Override
public void run() {
int messageNo = 1;
try {
while (true) {
ConsumerRecords<String, String> msgList = consumer.poll(1000);
if (null != msgList && msgList.count() > 0) {
for (ConsumerRecord<String, String> record : msgList) {
System.out.println("=> topic : kafka_test " + messageNo + "=> receive: key => " + record.key() + ", value => " + record.value() + " offset => " + record.offset());
messageNo++;
}
} else {
Thread.sleep(1000);
}
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
consumer.close();
}
}
public static void main(String args[]) {
MsgKafkaConsumer test1 = new MsgKafkaConsumer("kafka_test");
Thread thread1 = new Thread(test1);
thread1.start();
}
}