<properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>3.0.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.7</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.3</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

package com.warybee;
import org.apache.kafka.clients.producer.*;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
/**
 * @author joy
 */
public class KafkaProducerDemo {
    public static void main(String[] args) throws ExecutionException, InterruptedException, TimeoutException {
        Map<String, Object> configs = new HashMap<>();
        // 設(shè)置連接Kafka的初始連接用到的服務(wù)器地址
        configs.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "http://192.168.235.132:9092");
        // 設(shè)置key的序列化類(lèi)
        configs.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.IntegerSerializer");
        // 設(shè)置value的序列化類(lèi)
        configs.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer");
        configs.put(ProducerConfig.ACKS_CONFIG,"all");
        KafkaProducer<Integer,String> kafkaProducer=new KafkaProducer<Integer, String>(configs);
        //發(fā)送100條消息
        for (int i = 0; i < 100; i++) {
            ProducerRecord<Integer,String> producerRecord=new ProducerRecord<>
                    (       "test_topic_1",
                            0,
                            i,
                            "test topic msg "+i);
            //消息的異步確認(rèn)
            kafkaProducer.send(producerRecord, new Callback() {
                @Override
                public void onCompletion(RecordMetadata recordMetadata, Exception exception) {
                    if (exception==null){
                        System.out.println("消息的主題："+recordMetadata.topic());
                        System.out.println("消息的分區(qū)："+recordMetadata.partition());
                        System.out.println("消息的偏移量："+recordMetadata.offset());
                    }else {
                        System.out.println("發(fā)送消息異常");
                    }
                }
            });
        }
        // 關(guān)閉生產(chǎn)者
        kafkaProducer.close();
    }
}

package com.warybee;
import org.apache.kafka.clients.consumer.*;
import org.apache.kafka.common.TopicPartition;
import java.time.Duration;
import java.util.*;
/**
 * @author joy
 */
public class KafkaConsumerDemo {
    public static void main(String[] args) {
        Map<String, Object> configs = new HashMap<>();
        // 設(shè)置連接Kafka的初始連接用到的服務(wù)器地址
        // 如果是集群，則可以通過(guò)此初始連接發(fā)現(xiàn)集群中的其他broker
        configs.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "http://192.168.235.132:9092");
        //KEY反序列化類(lèi)
        configs.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.IntegerDeserializer");
        //value反序列化類(lèi)
        configs.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringDeserializer");
        configs.put(ConsumerConfig.GROUP_ID_CONFIG, "consumer.demo");
        configs.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
        //創(chuàng)建消費(fèi)者對(duì)象
        KafkaConsumer<Integer, String> consumer = new KafkaConsumer<Integer, String>(configs);
        List<String> topics = new ArrayList<>();
        topics.add("test_topic_1");
        //消費(fèi)者訂閱主題
        consumer.subscribe(topics);
        while (true){
            //批量拉取主題消息,每3秒拉取一次
            ConsumerRecords<Integer, String> records = consumer.poll(3000);
            //變量消息
            for (ConsumerRecord<Integer, String> record : records) {
                System.out.println("主題："+record.topic() + "\t"
                       +"分區(qū)：" + record.partition() + "\t"
                        +"偏移量：" +  + record.offset() + "\t"
                        +"Key："+ record.key() + "\t"
                        +"Value："+ record.value());
            }
        }
    }
}

java.net.ConnectException: Connection refused: no further information
   ............................省略其他錯(cuò)誤信息...................

# The address the socket server listens on. It will get the value returned from 
# java.net.InetAddress.getCanonicalHostName() if not configured.
#   FORMAT:
#     listeners = listener_name://host_name:port
#   EXAMPLE:
#     listeners = PLAINTEXT://your.host.name:9092
#listeners=PLAINTEXT://:9092
listeners = PLAINTEXT://localhost:9092