kafka复习:(23)事务

一、生产者,开启事务。

复制代码
package com.cisdi.dsp.modules.metaAnalysis.rest.kafka2023;


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

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

public class KafkaTest22 {
    public static void main(String[] args) {
        Properties properties= new Properties();

        properties.setProperty(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        properties.setProperty(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        properties.setProperty(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"xx.xx.xx.xx:9092");
        properties.setProperty(ProducerConfig.ENABLE_IDEMPOTENCE_CONFIG, "true");
        properties.setProperty(ProducerConfig.RETRIES_CONFIG, "2");
        properties.setProperty(ProducerConfig.MAX_IN_FLIGHT_REQUESTS_PER_CONNECTION, "4");
        properties.setProperty(ProducerConfig.TRANSACTIONAL_ID_CONFIG, "myTransaction");

        KafkaProducer<String,String> kafkaProducer=new KafkaProducer<String, String>(properties);
        ProducerRecord<String,String> producerRecord=new ProducerRecord<>("study2024",0,"fff","hello sister,now is: "+ new Date());
        kafkaProducer.initTransactions();
        kafkaProducer.beginTransaction();
        try{
            Future<RecordMetadata> future = kafkaProducer.send(producerRecord);
            long offset = 0;
            try {
                offset = future.get().offset();
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (ExecutionException e) {
                e.printStackTrace();
            }
            System.out.println(offset);

            Thread.sleep(60000);
            kafkaProducer.commitTransaction();
        } catch (Exception ex){
            kafkaProducer.abortTransaction();
        }


        kafkaProducer.close();
    }
}

二、消费者,设置隔离级别为"read_committed"

复制代码
package com.cisdi.dsp.modules.metaAnalysis.rest.kafka2023;

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.TopicPartition;
import org.apache.kafka.common.serialization.StringDeserializer;
import org.apache.kafka.common.serialization.StringSerializer;

import java.time.Duration;
import java.time.temporal.TemporalUnit;
import java.util.Arrays;
import java.util.Properties;
import java.util.concurrent.TimeUnit;

public class KafkaTest23 {

    private static Properties getProperties(){
        Properties properties=new Properties();

        properties.setProperty(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
        properties.setProperty(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
        properties.setProperty(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,"xx.xx.xx.xx:9092");
        properties.setProperty(ConsumerConfig.GROUP_ID_CONFIG,"testGroup");
        properties.setProperty(ConsumerConfig.ISOLATION_LEVEL_CONFIG, "read_committed");
        //properties.setProperty(ConsumerConfig.ISOLATION_LEVEL_CONFIG, "read_uncommitted");
        return properties;
    }
    public static void main(String[] args) {

        KafkaConsumer<String,String> myConsumer=new KafkaConsumer<String, String>(getProperties());
        String topic="study2024";
        myConsumer.subscribe(Arrays.asList(topic));

        while(true){
            ConsumerRecords<String,String> consumerRecords=myConsumer.poll(Duration.ofMillis(5000));
            for(ConsumerRecord record: consumerRecords){
                System.out.println(record.value());
                System.out.println("record offset is: "+record.offset());
            }

        }



    }
}

三、运行结果,按照上述配置,当生产者发送消息并从kafka broker获取到offset后就会sleep,在生产者sleep的时候,消费者是获取不到消息的,只有sleep完成并提交事务之后,消费者才会获取到消息

相关推荐
Cachel wood9 天前
Spark教程6:Spark 底层执行原理详解
大数据·数据库·分布式·计算机网络·spark
找不到、了9 天前
kafka消费的模式及消息积压处理方案
java·kafka
超级小忍9 天前
Spring Boot 集成 Apache Kafka 实战指南
spring boot·kafka·apache
Ting-yu9 天前
零基础学习RabbitMQ(1)--概述
分布式·学习·rabbitmq
寒山李白9 天前
分布式ID生成方式及优缺点详解
数据库·分布式·分布式id生成方式
acrel158215962219 天前
光伏电站 “智慧大脑”:安科瑞 Acrel-1000DP 分布式监控系统技术解析
分布式·分布式光伏·安科瑞电气
Cachel wood10 天前
Spark教程1:Spark基础介绍
大数据·数据库·数据仓库·分布式·计算机网络·spark
沉着的码农10 天前
【分布式】Redisson滑动窗口限流器原理
java·redis·分布式·redisson
小葛呀10 天前
在大数据求职面试中如何回答分布式协调与数据挖掘问题
大数据·分布式·机器学习·面试·数据挖掘·互联网·技术栈
阳光下是个孩子10 天前
基于 Spark 实现 COS 海量数据处理
大数据·分布式·spark