kafka demo最简单的实现

包的结构

pom.xml相关的依赖：

  <dependencies>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.0.0</version>
        </dependency>
    </dependencies>

Producer类：

package com;

import org.apache.kafka.clients.producer.*;
import org.apache.kafka.common.serialization.StringSerializer;

import java.util.Properties;
import java.util.concurrent.ExecutionException;

/**
 * @author Modesty.P.Gao
 * @version 1.0
 * @description: TODO
 * @date 11/11/2021 3:25 PM
 */
public class Producer {
    
    

    private static final String TOPIC="demo";
    private static final String BPOKER_LIST="localhost:9092";
    private static KafkaProducer<String,String> producer=null;
    static {
    
    
        Properties configs=initConfig();
        producer=new KafkaProducer<String, String>(configs);
    }

    private static Properties initConfig() {
    
    
        Properties properties=new Properties();
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,BPOKER_LIST);
        properties.put(ProducerConfig.ACKS_CONFIG,"all");
        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,StringSerializer.class.getName());
        return properties;

    }

    public static void main(String[] args) {
    
    
        final String message="hello world Modesty";
        ProducerRecord<String,String> record =new ProducerRecord<String, String>(TOPIC,message);
        try {
    
    
            producer.send(record, new Callback() {
    
    
                public void onCompletion(RecordMetadata metadata, Exception exception) {
    
    
                    if (null==exception){
    
    
                        System.out.println("perfect");
                    }
                    if (null!=metadata){
    
    
                        System.out.println("offset:"+metadata.offset()+";partition:"+metadata.partition());
                    }
                }
            }).get();
        } catch (InterruptedException e) {
    
    
            e.printStackTrace();
        } catch (ExecutionException e) {
    
    
            e.printStackTrace();
        }finally {
    
    
            producer.close();
        }
    }

}

Consumer类

package com;


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

import java.util.Arrays;
import java.util.Properties;

/**
 * @author Modesty.P.Gao
 * @version 1.0
 * @description: TODO
 * @date 11/11/2021 4:02 PM
 */
public class Consumer {
    
    
    private static final String TOPIC="demo";
    private static final String BPOKER_LIST="localhost:9092";
    private static KafkaConsumer<String, String> consumer = null;

    static {
    
    
        Properties properties = initConfig();
        consumer = new KafkaConsumer<String, String>(properties);
        consumer.subscribe(Arrays.asList(TOPIC));
    }

    private static Properties initConfig() {
    
    
        Properties properties = new Properties();
        properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,BPOKER_LIST);
        properties.put(ConsumerConfig.GROUP_ID_CONFIG,"test");
        properties.put(ConsumerConfig.CLIENT_ID_CONFIG,"test");
        properties.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
        properties.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG,StringDeserializer.class.getName());
        return properties;

    }

    public static void main(String[] args) {
    
    
        try {
    
    
            while (true) {
    
    
                ConsumerRecords<String, String> records = consumer.poll(100);
                for (ConsumerRecord<String, String> record : records) {
    
    
                    try {
    
    
                        System.out.println(record.value());
                    } catch (Exception e) {
    
    
                        e.printStackTrace();
                    }
                }
            }
        } catch (Exception e) {
    
    
            e.printStackTrace();
        } finally {
    
    
            consumer.close();
        }
    }
}

运行结果