1、SpringBoot集成kafka接收消息

生产者

package com.power.producer;

import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;

@Component
public class EventProducer {

    @Resource
    private KafkaTemplate<String,String> kafkaTemplate;

    public void sendEvent(){
        kafkaTemplate.send("helloTopic","hello kafka");
    }

}

application.yml配置文件

spring:
  application:
    #应用名称
    name: spring-boot-02-kafka-base

  #kafka连接地址（ip+port）
  kafka:
    bootstrap-servers: 47.116.35.15:9092
    #配置生产者(有24个配置)
#    producer:


    #配置消费者(有24个配置)
#    consumer:

测试类

package com.power;

import com.power.producer.EventProducer;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;

import javax.annotation.Resource;

@SpringBootTest
public class SpringBoot02KafkaBaseApplication {

    @Resource
    private EventProducer eventProducer;

    @Test
    void sendInterceptor(){
        eventProducer.sendEvent();
    }

}

2、@Payload注解接收消息体内容

消费者：

package com.power.consumer;

import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.stereotype.Component;

@Component
public class EventConsumer {

    //采用监听的方式接收事件（消息，数据）
    @KafkaListener(topics = {"helloTopic"},groupId="helloGroup")
    public void onEvent(@Payload String event){
        System.out.println("读取/消费到的事件："+event);
    }
}

测试结果：

3、@Header注解接收消息头内容

注意，不太版本kafak使用@Header注解读取partition时不一样：

• kafka3.0以下版本使用KafkaHeaders.RECEIVED_PARTITION_ID获取分区
• kafka3.0以上版本使用KafkaHeaders.RECEIVED_PARTITION获取分区

消费者：

package com.power.consumer;

import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.kafka.support.KafkaHeaders;
import org.springframework.messaging.handler.annotation.Header;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.stereotype.Component;

@Component
public class EventConsumer {

    //采用监听的方式接收事件（消息，数据）
    @KafkaListener(topics = {"helloTopic"},groupId="helloGroup")
        public void onEvent(@Payload String event,
                            @Header(value=KafkaHeaders.RECEIVED_TOPIC) String topic,
                            @Header(value=KafkaHeaders.RECEIVED_PARTITION_ID) String partition){
        System.out.println("读取/消费到的事件："+event+",topic："+topic+",partition："+partition);
    }
}

测试结果：

4、接收消息所有内容

消费者：

package com.power.consumer;

import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.kafka.support.KafkaHeaders;
import org.springframework.messaging.handler.annotation.Header;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.stereotype.Component;

import java.util.function.Consumer;

@Component
public class EventConsumer {

    //采用监听的方式接收事件（消息，数据）
    @KafkaListener(topics = {"helloTopic"},groupId="helloGroup")
        public void onEvent(@Payload String event,
                            @Header(value=KafkaHeaders.RECEIVED_TOPIC) String topic,
                            @Header(value=KafkaHeaders.RECEIVED_PARTITION_ID) String partition,
                            ConsumerRecord<String,String> record){
        System.out.println("读取/消费到的事件："+event+",topic："+topic+",partition："+partition);
        System.out.println("读取/消费到的事件："+record.toString());
    }
}

测试打印所有消息：