28、springboot整合RabbitMQ（2）

1、监听

1.1、监听队列

如订单系统和库存系统

订单系统下订单之后将消息存放在消息队列中

库存系统需要时刻进行监听消息队列的内容，有新的订单就需要进行库存相关的操作

 

此时模拟监听消息队列中的Book信息

 

监听类：

@RabbitListener监听相关的消息队列

@Service
public class BookService {
    @RabbitListener(queues = "atguigu.news")
    public void receive(Book book){
        System.out.println("收到消息：" + book);
    }
}

开启关于RabbitMq注解

//开启基于注解RabbitMq模式
@EnableRabbit
@SpringBootApplication
public class AmqpApplication {

    public static void main(String[] args) {
        SpringApplication.run(AmqpApplication.class, args);
    }
}

后台的监听结果

1.2、获取消息头、消息体相关的参数

import org.springframework.stereotype.Service;

@Service
public class BookService {
    @RabbitListener(queues = "atguigu.news")
    public void receive(Book book){
        System.out.println("收到消息：" + book);
    }

    //import org.springframework.amqp.core.Message;
    @RabbitListener(queues = "atguigu")
    public void receive02(Message message){
        System.out.println(message.getBody());
        System.out.println(message.getMessageProperties());
    }

}

打印的数据

[B@2d4a67c8
MessageProperties [headers={__TypeId__=com.cr.amqp.pojo.Book}, contentType=application/json, contentEncoding=UTF-, contentLength=, receivedDeliveryMode=PERSISTENT, priority=, redelivered=true, receivedExchange=exchange.fanout, receivedRoutingKey=, deliveryTag=, consumerTag=amq.ctag-193ojwCpIAgVmLfB52Prkg, consumerQueue=atguigu]
收到消息：com.cr.amqp.pojo.Book@74095f6e

2、创建

假设有些信道活着队列不存在的情况

可以使用AmqpAdmin进行创建交换器，转换规则、队列（Queue、Exchange、Binding）

@Autowired
AmqpAdmin amqpAdmin;

//创建交换器
@Autowired
AmqpAdmin amqpAdmin;

public void createExchange(){

    //package org.springframework.amqp.core;
    //public interface Exchange extends Declarable
    amqpAdmin.declareExchange(new DirectExchange("amqp.exchange"));
}

结果：

交换器的类：

创建队列：

amqpAdmin.declareQueue(new Queue("amqpadmin.queue"));

绑定规则：

//绑定规则
amqpAdmin.declareBinding(new Binding("amqpadmin.queue",Binding.DestinationType.QUEUE,"amqp.exchange","amqp.aa",null));