记录spring rabbitmq简单的使用遇到的问题

写了个最简单的例子，用默认的交换机。

准备：pom.xm的配置

<?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>com.neo</groupId>
    <artifactId>spring-boot-rabbitmq</artifactId>
    <version>1.0.0</version>
    <packaging>jar</packaging>

    <name>spring-boot-rabbitmq</name>
    <description>Demo project for Spring Boot and rabbitmq</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.0.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
    
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
    

</project>

1.配置类

package com.neo.rabbit;

import org.springframework.amqp.core.Queue;
import org.springframework.amqp.rabbit.connection.CachingConnectionFactory;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;


@Configuration
public class RabbitConfig {

    @Bean
    public ConnectionFactory getConn(){
        CachingConnectionFactory factory = new CachingConnectionFactory("127.0.0.1");
        factory.setUsername("guest");
        factory.setPassword("guest");
        return factory;
    }

    @Bean
    public Queue helloQueue() {
        return new Queue("hello");
    }

}

2.消息发送者:注意下划线的那栏

package com.neo.rabbit.hello;

import org.springframework.amqp.core.AmqpTemplate;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.Date;

@Component
public class HelloSender {

    @Autowired
    private AmqpTemplate rabbitTemplate;

    public void send() {
        String context = "hello " + new Date();
        System.out.println("Sender : " + context);
        this.rabbitTemplate.convertAndSend("msg", context);
    }

}

3.消息接收者

package com.neo.rabbit.hello;

import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Component;

import java.util.Date;

@Component
@RabbitListener(queues = "hello")
public class HelloReceiver {

    @RabbitHandler
    public void process(String msg) {
        System.out.println("Receiver  : " + msg);
    }

}

4.写个控制器测试

package com.neo.controller;

import com.neo.rabbit.hello.HelloSender;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class RabbitController {

    @Autowired
    private HelloSender helloSender;

    @RequestMapping("/hello")
    public String hello(String msg){
        helloSender.send();
        return "success";
    }


}

运行：localhost:8080/hello

结果发送消息可以，但是收不到消息，代码研究了半天，后面发现是消息发送者HelloSender 

里面的下划线部分问题。

发送消息的时候，需要对应的已注入队列：queue名称。

代码修改为：

this.rabbitTemplate.convertAndSend("hello", context);

即可。