Kafka3.2教程（三）Java操作Kafka

在hp2上启动kafka
在IDEA中新建Maven项目，引入Kafka客户端依赖：

<dependency>
    <groupId>org.apache.kafkagroupId>
    <artifactId>kafka-clientsartifactId>
    <version>3.2.0version>
dependency>

生产者：

package com.alan;


import java.util.Properties;
import java.util.Random;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.serialization.StringSerializer;

public class Producer {
    public static String topic = "hello";//定义主题

    public static void main(String[] args) throws InterruptedException {
        Properties p = new Properties();
        p.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "hp2:9092");//kafka地址，多个地址用逗号分割
        p.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
        p.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
        KafkaProducer<String, String> kafkaProducer = new KafkaProducer<>(p);

        try {
            while (true) {
                String msg = "Hello," + new Random().nextInt(100);
                ProducerRecord<String, String> record = new ProducerRecord<String, String>(topic, msg);
                kafkaProducer.send(record);
                System.out.println("消息发送成功:" + msg);
                Thread.sleep(3000);
            }
        } finally {
            kafkaProducer.close();
        }

    }
}

消费者：

package com.alan;


import java.util.Collections;
import java.util.Properties;

import org.apache.kafka.clients.consumer.ConsumerConfig;
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;

@SuppressWarnings("deprecation")
public class Consumer {
    public static void main(String[] args) {
        Properties p = new Properties();
        p.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.150.102:9092");
        p.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        p.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        p.put(ConsumerConfig.GROUP_ID_CONFIG, "hello");

        KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<String, String>(p);
        kafkaConsumer.subscribe(Collections.singletonList(Producer.topic));// 订阅消息

        while (true) {
            ConsumerRecords<String, String> records = kafkaConsumer.poll(100);
            for (ConsumerRecord<String, String> record : records) {
                System.out.println(String.format("topic:%s,offset:%d,消息:%s", //
                        record.topic(), record.offset(), record.value()));
            }
        }
    }
}