依赖

<dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.3.0</version>
</dependency>

生产者

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;
import java.util.Properties;

public class HelloKafkaProducer {

    public static void main(String[] args) {
        //TODO 生产者三个属性必须指定(broker地址清单、key和value的序列化器)
        Properties properties = new Properties();
        properties.put("bootstrap.servers","192.168.100.14:9092");
        properties.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        properties.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        KafkaProducer<String,String> producer = new KafkaProducer(properties);
        try {
            ProducerRecord<String,String> record;
            try {
                //TODO 发送4条消息
                for(int i=0;i<4;i++){
                    record = new ProducerRecord("hello-topic", null,"hello");
                    producer.send(record);//发送并发忘记（重试会有）
                    System.out.println(i+"，message is sent");
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        } finally {
            producer.close();
        }
    }
}

消费者

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;
import java.time.Duration;
import java.util.Collections;
import java.util.Properties;

public class HelloKafkaConsumer {

    public static void main(String[] args) {
        //TODO 消费者三个属性必须指定(broker地址清单、key和value的反序列化器)
        Properties properties = new Properties();
        properties.put("bootstrap.servers","192.168.100.14:9092");
        properties.put("key.deserializer", StringDeserializer.class);
        properties.put("value.deserializer", StringDeserializer.class);

        //TODO 群组并非完全必须
        properties.put(ConsumerConfig.GROUP_ID_CONFIG,"test1");
        KafkaConsumer<String,String> consumer = new KafkaConsumer(properties);
        try {
            //TODO 消费者订阅主题（可以多个）
            consumer.subscribe(Collections.singletonList("hello-topic"));
            while(true){
                //TODO 拉取（新版本）,会把元数据获取也计入整个超时时间
                ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(500));
                for(ConsumerRecord<String, String> record:records){
                    System.out.println(String.format("topic:%s,分区：%d,偏移量：%d," + "key:%s,value:%s",record.topic(),record.partition(),
                            record.offset(),record.key(),record.value()));
                    //do my work
                    //打包任务投入线程池
                }
            }
        } finally {
            consumer.close();
        }
    }
}