SpringBoot+RabbitMQ实现发布订阅模式消息队列

文章目录

• 一、适用场景
• 二、前提条件
• 三、执行流程
• 四、实现方法
• • 1.依赖包
  • 2.application配置文件
  • 3.创建一个接收消息的对象
  • 4.创建三个消息队列绑定到一个发布订阅交换机上
  • 5.创建三个队列的消费者
  • 6.controller中创建一个生产者
• 五、测试结果

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一、适用场景

高并发场景下，多个耗时业务顺序执行会浪费大量时间，多线程又会导致过高的cpu占用，较好的方式是采用消息队列。

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二、前提条件

需要先部署一个RabbitMQ，可以参考这个教程
https://blog.csdn.net/weixin_43721000/article/details/124587795

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三、执行流程

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四、实现方法 1.依赖包

 <dependency>
     <groupId>org.springframework.bootgroupId>
     <artifactId>spring-boot-starter-amqpartifactId>
 dependency>


<dependency>
     <groupId>org.springframework.bootgroupId>
     <artifactId>spring-boot-starter-webartifactId>
 dependency>
 <dependency>
     <groupId>org.projectlombokgroupId>
     <artifactId>lombokartifactId>
 dependency>
 <dependency>
     <groupId>com.alibabagroupId>
     <artifactId>fastjsonartifactId>
     <version>1.2.9version>
 dependency>
 

2.application配置文件

server:
  port: 8080

spring:
  rabbitmq:
    host: 192.168.0.231			# RabbitMQ主机ip
    port: 5672					# RabbitMQ端口
    username: admin				# 用户名
    password: 123456			# 密码
    virtual-host: my_vhost		# 虚拟主机名【用于隔离不同用户创建的消息队列】

3.创建一个接收消息的对象

package com.cxstar.bean;

import lombok.Data;

@Data
public class MsgBean {
    private String searchKey;
    private Integer curPage;
	
	// fastjson的json转对象的方法需要一个无参构造
    public MsgBean() {}

    public MsgBean(String searchKey, Integer curPage) {
        this.searchKey = searchKey;
        this.curPage = curPage;
    }

}

4.创建三个消息队列绑定到一个发布订阅交换机上

package com.cxstar.config;

import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.FanoutExchange;
import org.springframework.amqp.core.Queue;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class FanoutExchangeConfig {

    // 新建发布订阅交换机，并将队列A B C绑定到该交换机

    // 命名 ------------------------------------------------------------------------
    // 交换机名
    public static final String FANOUT_EXCHANGE = "fanout_exchange";
    // 队列名
    public static final String FANOUT_EXCHANGE_QUEUE_A = "fanout_exchange_queue_a";
    public static final String FANOUT_EXCHANGE_QUEUE_B = "fanout_exchange_queue_b";
    public static final String FANOUT_EXCHANGE_QUEUE_C = "fanout_exchange_queue_c";
    // -----------------------------------------------------------------------------

    // 创建 ------------------------------------------------------------------------
    // 创建交换机
    @Bean
    FanoutExchange fanoutExchange() {
        return new FanoutExchange(FANOUT_EXCHANGE);
    }
    // 创建队列
    @Bean
    public Queue queueA(){
        return new Queue(FANOUT_EXCHANGE_QUEUE_A);
    }
    @Bean
    public Queue queueB(){
        return new Queue(FANOUT_EXCHANGE_QUEUE_B);
    }
    @Bean
    public Queue queueC(){
        return new Queue(FANOUT_EXCHANGE_QUEUE_C);
    }
    // -----------------------------------------------------------------------------

    // 将三个队列绑定到交换机上【队列订阅交换机】 ------------------------------------------------------------------
    @Bean
    Binding bindingExchangeA() {
        return BindingBuilder.bind(queueA()).to(fanoutExchange());
    }
    @Bean
    Binding bindingExchangeB() {
        return BindingBuilder.bind(queueB()).to(fanoutExchange());
    }
    @Bean
    Binding bindingExchangeC() {
        return BindingBuilder.bind(queueC()).to(fanoutExchange());
    }
    // ---------------------------------------------------------------------------------------
}

5.创建三个队列的消费者

package com.cxstar.consumer;

import com.alibaba.fastjson.JSONObject;
import com.cxstar.bean.MsgBean;
import com.cxstar.config.FanoutExchangeConfig;
import com.rabbitmq.client.Channel;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

import java.io.IOException;

@Slf4j
@Component
public class Consumer {
	
	// 消费者A
    @RabbitListener(queues = FanoutExchangeConfig.FANOUT_EXCHANGE_QUEUE_A)
    public void receiverQueueA(String msg, Channel channel, Message message) throws IOException {

        // 消息转对象
        MsgBean msgBean = JSONObject.toJavaObject(JSONObject.parseObject(msg), MsgBean.class);
		
		// 消费
        log.info("receiverQueueA 消费对象："+msgBean.toString());

    }
	
	// 消费者B
    @RabbitListener(queues = FanoutExchangeConfig.FANOUT_EXCHANGE_QUEUE_B)
    public void receiverQueueB(String msg, Channel channel, Message message) throws IOException {

        // 消息转对象
        MsgBean msgBean = JSONObject.toJavaObject(JSONObject.parseObject(msg), MsgBean.class);
		
		// 消费
        log.info("receiverQueueB 消费对象："+msgBean.toString());

    }
	
	// 消费者C
    @RabbitListener(queues = FanoutExchangeConfig.FANOUT_EXCHANGE_QUEUE_C)
    public void receiverQueueC(String msg, Channel channel, Message message) throws IOException {

        // 消息转对象
        MsgBean msgBean = JSONObject.toJavaObject(JSONObject.parseObject(msg), MsgBean.class);
		
		// 消费
        log.info("receiverQueueC 消费对象："+msgBean.toString());

    }
}

6.controller中创建一个生产者

package com.cxstar.controller;

import com.alibaba.fastjson.JSONObject;
import com.cxstar.bean.MsgBean;
import com.cxstar.config.FanoutExchangeConfig;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

@RestController
public class Controller {

    @Resource
    private RabbitTemplate rabbitTemplate;

    @GetMapping("/send_msg")
    public void sendExchange(){
		
		// 创建消息
        MsgBean msgBean = new MsgBean();
        msgBean.setSearchKey("python");
        msgBean.setCurPage(1);
        String msgBeanJsonString = JSONObject.toJSONString(msgBean);
		
		// 生产者发布消息到交换机
        rabbitTemplate.convertAndSend(FanoutExchangeConfig.FANOUT_EXCHANGE, null, msgBeanJsonString);

    }
}

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五、测试结果

启动 SpringBoot
访问 127.0.0.1:8080/send_msg