Kafka（七）------Kafka实战

àì夳堔傛蜴生んèń 2022-12-20 11:15 156阅读 0赞

## 1、概述 ##

消息生产者发送消息，消费消费者消费消息  
![在这里插入图片描述][20201111223651597.png_pic_center]

**准备工作：kafak环境搭建部署**

参考

[Kafka（一）------Linux环境下Kafka集群安装][Kafka_------Linux_Kafka]  
[Kafka（二）------Windows环境下Kafka安装][Kafka_------Windows_Kafka]

**创建topic与partitions**

bin/kafka-topics.sh --create --zookeeper localhost:2181 --replication-factor 1 --partitions 1 --topic kafkaTopic1

选项说明：

–topic ： topic名称  
–replication ： 副本数  
–partitions : 分区数

## 2、spring-boot-kafka-producer生产者创建 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70_pic_center]

server:
      servlet:
        context-path: /spring-boot-kafka-producer
      port: 8888
    spring:
      kafka:
        bootstrap-servers: 127.0.0.1:9092
        #生产者的配置，大部分我们可以使用默认的，这里列出几个比较重要的属性
        producer:
          #每批次发送消息的数量
          batch-size: 16
          #设置大于0的值将使客户端重新发送任何数据，一旦这些数据发送失败。注意，这些重试与客户端接收到发送错误时的重试没有什么不同。允许重试将潜在的改变数据的顺序，如果这两个消息记录都是发送到同一个partition，则第一个消息失败第二个发送成功，则第二条消息会比第一条消息出现要早。
          retries: 0
          #producer可以用来缓存数据的内存大小。如果数据产生速度大于向broker发送的速度，producer会阻塞或者抛出异常，以“block.on.buffer.full”来表明。这项设置将和producer能够使用的总内存相关，但并不是一个硬性的限制，因为不是producer使用的所有内存都是用于缓存。一些额外的内存会用于压缩（如果引入压缩机制），同样还有一些用于维护请求。
          buffer-memory: 33554432
          #key序列化方式
          key-serializer: org.apache.kafka.common.serialization.StringSerializer
          value-serializer: org.apache.kafka.common.serialization.StringSerializer

package com.kafka.producer;
    
    import java.util.Date;
    
    /**
     * 自定义发送消息格式实体类
     *
     * @author yl
     * @version 1.0
     * @className Message
     * @date 2020/7/23 21:53
     **/
    public class Message {
    
        private String id;
    
        private String msg;
    
        private Date sendTime;
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getMsg() {
            return msg;
        }
    
        public void setMsg(String msg) {
            this.msg = msg;
        }
    
        public Date getSendTime() {
            return sendTime;
        }
    
        public void setSendTime(Date sendTime) {
            this.sendTime = sendTime;
        }
    
        @Override
        public String toString() {
            return "Message{" +
                    "id='" + id + '\'' +
                    ", msg='" + msg + '\'' +
                    ", sendTime=" + sendTime +
                    '}';
        }
    }

package com.kafka.producer;
    
    import com.alibaba.fastjson.JSONObject;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.kafka.core.KafkaTemplate;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    import java.util.Date;
    import java.util.UUID;
    
    /**
     * 生产者消息发送控制层
     *
     * @author yl
     * @version 1.0
     * @className SendController
     * @date 2020/7/23 21:55
     **/
    @RestController
    @RequestMapping("/kafka")
    public class ProducerController {
    
        @Autowired
        private KafkaTemplate kafkaTemplate;
    
        @GetMapping(value = "/send")
        public String send() {
            Message message = new Message();
            message.setId(UUID.randomUUID().toString());
            message.setMsg("kakfa消息内容");
            message.setSendTime(new Date());
            System.out.println("消息发送成功==" + message.toString());
            kafkaTemplate.send("kafkaTopic1", JSONObject.toJSONString(message));
            return "消息发送成功！";
        }
    }

package com.kafka;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SpringBootKafkaProducerApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(SpringBootKafkaProducerApplication.class, args);
        }
    
    }

## 3、spring-boot-kafka-consumer 消费者创建 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70_pic_center 1]

server:
      servlet:
        context-path: /spring-boot-kafka-consumer
      port: 9999
    spring:
      kafka:
        bootstrap-servers: 127.0.0.1:9092
        #消费者的配置
        consumer:
          #Kafka中没有初始偏移或如果当前偏移在服务器上不再存在时,默认区最新 ，有三个选项 【latest, earliest, none】
          auto-offset-reset: latest
          #是否开启自动提交
          enable-auto-commit: true
          #自动提交的时间间隔
          auto-commit-interval: 100
          #key的解码方式
          key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
          #value的解码方式
          value-deserializer: org.apache.kafka.common.serialization.StringDeserializer
          #在/usr/local/etc/kafka/consumer.properties中有配置
          group-id: test-consumer-group

package com.kafka.consumer;
    
    import com.alibaba.fastjson.JSONObject;
    import org.apache.kafka.clients.consumer.ConsumerRecord;
    import org.springframework.kafka.annotation.KafkaListener;
    import org.springframework.stereotype.Component;
    import java.util.Optional;
    
    /**
     * 消费者端消费消息
     * @className ConsumerMessageHandler
     * @author yl
     * @date 2020/7/23 21:57
     * @version 1.0
     **/
    @Component
    public class ConsumerMessageHandler {
    
        @KafkaListener(topics = {"kafkaTopic1"})
        public void listen(ConsumerRecord<?, ?> record){
            Optional<?> kafkaMessage = Optional.ofNullable(record.value());
            if (kafkaMessage.isPresent()) {
                Object object = kafkaMessage.get();
                System.out.println("---->"+record);
                System.out.println("消费者端消费消息：---->"+object.toString());
            }
        }
    }

package com.kafka.consumer;
    
    import java.util.Date;
    
    /**
     * 自定义发送消息格式实体类
     *
     * @author yl
     * @version 1.0
     * @className Message
     * @date 2020/7/23 21:53
     **/
    public class Message {
    
        private String id;
    
        private String msg;
    
        private Date sendTime;
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getMsg() {
            return msg;
        }
    
        public void setMsg(String msg) {
            this.msg = msg;
        }
    
        public Date getSendTime() {
            return sendTime;
        }
    
        public void setSendTime(Date sendTime) {
            this.sendTime = sendTime;
        }
    
        @Override
        public String toString() {
            return "Message{" +
                    "id='" + id + '\'' +
                    ", msg='" + msg + '\'' +
                    ", sendTime=" + sendTime +
                    '}';
        }
    }

package com.kafka;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class SpringBootKafkaConsumerApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(SpringBootKafkaConsumerApplication.class, args);
        }
    
    }

--------------------

git项目源码地址：[https://github.com/yilei111/spring-boot-kafka.git][https_github.com_yilei111_spring-boot-kafka.git]

[20201111223651597.png_pic_center]: /images/20221120/e2a1661576b14a44917eee4864383962.png
[Kafka_------Linux_Kafka]: https://blog.csdn.net/qq_29914837/article/details/106741120
[Kafka_------Windows_Kafka]: https://blog.csdn.net/qq_29914837/article/details/106845925
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70_pic_center]: https://img-blog.csdnimg.cn/20201111223947801.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3,size_16,color_FFFFFF,t_70#pic_center
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3_size_16_color_FFFFFF_t_70_pic_center 1]: https://img-blog.csdnimg.cn/20201111224155166.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI5OTE0ODM3,size_16,color_FFFFFF,t_70#pic_center
[https_github.com_yilei111_spring-boot-kafka.git]: https://github.com/yilei111/spring-boot-kafka.git