idea maven项目操作kafka--生产者和消费者

一、创建maven项目

二、添加依赖pom.xml

https://maven.aliyun.com/mvn/search

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>kafka_cnn</artifactId>
    <version>1.0-SNAPSHOT</version>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>

        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.2.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-streams</artifactId>
            <version>2.2.1</version>
        </dependency>

        <dependency>
            <groupId> org.apache.cassandra</groupId>
            <artifactId>cassandra-all</artifactId>
            <version>0.8.1</version>

            <exclusions>
                <exclusion>
                    <groupId>org.slf4j</groupId>
                    <artifactId>slf4j-log4j12</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>log4j</groupId>
                    <artifactId>log4j</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

</project>

　　

三、创建消费者类ConsumerDemo.java

　

package com.kafka.consumer;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.clients.consumer.ConsumerRecords;
import org.apache.kafka.clients.consumer.KafkaConsumer;

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

/**
 * @program: kafka consumer test
 * @Date: 2021/05/15 21:55
 * @Author: kq
 * @Description:
 */
public class ConsumerDemo {
    public static void main(String[] args){
        Properties properties = new Properties();
      properties.put("bootstrap.servers", "192.168.1.12:9092");
        /**
         * consumer分组id
         */
        properties.put("group.id", "zabbix_perf");
        properties.put("enable.auto.commit", "true");
        properties.put("auto.commit.interval.ms", "1000");
        /**
         * earliest
         *   当各分区下有已提交的offset时，从提交的offset开始消费；无提交的offset时，从头开始消费
         *   latest
         *   当各分区下有已提交的offset时，从提交的offset开始消费；无提交的offset时，消费新产生的该分区下的数据
         *   none
         *   topic各分区都存在已提交的offset时，从offset后开始消费；只要有一个分区不存在已提交的offset，则抛出异常
         *
         */
        properties.put("auto.offset.reset", "earliest");
        properties.put("session.timeout.ms", "30000");
        /**
         * 反序列化
         * 把kafka集群二进制消息反序列化指定类型。
         */
        properties.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        properties.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> kafkaConsumer = new KafkaConsumer<>(properties);
        kafkaConsumer.subscribe(Arrays.asList("my-kafka-topic5"));
        while (true) {
            ConsumerRecords<String, String> records = kafkaConsumer.poll(100);//100是超时时间
            for (ConsumerRecord<String, String> record : records) {
                System.out.printf("offset = %d, value = %s", record.offset(), record.value());
                System.out.println();
            }
        }

    }
}

　　

　　

四、创建生产者类ProducerDemo.java

package com.kafka.producer;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;

import java.util.Properties;

/**
 * @program: kafka producer test
 * @Date: 2021/05/15 21:55
 * @Author: kq
 * @Description:
 */
public class ProducerDemo {
    public static void main(String[] args){

        Properties properties = new Properties();
        /**
         *bootstrap.server用于建立到Kafka集群的初始连接的主机/端口对的列表，如果有两台以上的机器，逗号分隔
         */
        properties.put("bootstrap.servers", "192.168.1.12:9092");
        /**
         * acks有三种状态
         * acks=0 不等待服务器确认直接发送消息，无法保证服务器收到消息数据
         * acks=1 把消息记录写到本地，但不会保证所有的消息数据被确认记录的情况下进行释放
         * acks=all 确认所有的消息数据被同步副本确认，这样保证了记录不会丢失
         *
         */
        properties.put("acks", "all");
        /**
         * 设置成大于0将导致客户端重新发送任何发送失败的记录
         *
         */
        properties.put("retries", 0);
        /**
         *16384字节是默认设置的批处理的缓冲区
         */
        properties.put("batch.size", 16384);

        properties.put("linger.ms", 1);
        properties.put("buffer.memory", 33554432);
        /**
         * 序列化类型。
         * kafka是以键值对的形式发送到kafka集群的，其中key是可选的，value可以是任意类型，Message再被发送到kafka之前，Producer需要
         * 把不同类型的消息转化成二进制类型。
         */
        properties.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        properties.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        Producer<String, String> producer = null;
        try {
            producer = new KafkaProducer<String, String>(properties);
            for (int i = 0; i < 5; i++) {
                String msg = "{Message " + i+"[{"partitions": [{"topic": "my-kafka-topic5", "partition": 4, "offset": 27}], "version":1 },{"partitions": [{"topic": "my-kafka-topic5", "partition": 4, "offset": 27}], "version":1 },{"partitions": [{"topic": "my-kafka-topic5", "partition": 4, "offset": 27}], "version":1 }]";
                producer.send(new ProducerRecord<String, String>("my-kafka-topic5", msg));
                System.out.println("Sent:" + msg);
            }
        } catch (Exception e) {
            e.printStackTrace();

        } finally {
            producer.close();
        }

    }
}