关于RabbitMQ服务器整合(二)

准备工作

15min
IDEA
maven 3.0

在开始构建项目之前，机器需要安装rabbitmq，你可以去官网下载，http://www.rabbitmq.com/download.html ，如果你是用的Mac（程序员都应该用mac吧），你可以这样下载：

1	`brew install rabbitmq`

安装完成后开启服务器：

1	`rabbitmq-server`

开启服务器成功，你可以看到以下信息：

RabbitMQ 3.1.3. Copyright (C) 2007-2013 VMware, Inc.

## ## Licensed under the MPL. See http://www.rabbitmq.com/

## ##

########## Logs: /usr/local/var/log/rabbitmq/rabbit@localhost.log

###### ## /usr/local/var/log/rabbitmq/rabbit@localhost-sasl.log

##########

Starting broker... completed with 6 plugins.

构建工程

构架一个SpringBoot工程，其pom文件依赖加上spring-boot-starter-amqp的起步依赖：

<dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-amqp</artifactId>

</dependency>

创建消息接收者

在任何的消息队列程序中，你需要创建一个消息接收者，用于响应发送的消息。

@Component

public class Receiver {

private CountDownLatch latch = new CountDownLatch(1);

public void receiveMessage(String message) {

System.out.println("Received <" + message + ">");

latch.countDown();

}

public CountDownLatch getLatch() {

return latch;

}

消息接收者是一个简单的POJO类，它定义了一个方法去接收消息，当你注册它去接收消息，你可以给它取任何的名字。其中，它有CountDownLatch这样的一个类，它是用于告诉发送者消息已经收到了，你不需要在应用程序中具体实现它，只需要latch.countDown()就行了。

创建消息监听，并发送一条消息

在spring程序中，RabbitTemplate提供了发送消息和接收消息的所有方法。你只需简单的配置下就行了：

需要一个消息监听容器
声明一个quene,一个exchange,并且绑定它们
一个组件去发送消息

代码清单如下：

package com.forezp;

import com.forezp.message.Receiver;

import org.springframework.amqp.core.Binding;

import org.springframework.amqp.core.BindingBuilder;

import org.springframework.amqp.core.Queue;

import org.springframework.amqp.core.TopicExchange;

import org.springframework.amqp.rabbit.connection.ConnectionFactory;

import org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer;

import org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.context.annotation.Bean;

@SpringBootApplication

public class SpringbootRabbitmqApplication {

final static String queueName = "spring-boot";

@Bean

Queue queue() {

return new Queue(queueName, false);

}

@Bean

TopicExchange exchange() {

return new TopicExchange("spring-boot-exchange");

}

@Bean

Binding binding(Queue queue, TopicExchange exchange) {

return BindingBuilder.bind(queue).to(exchange).with(queueName);

}

@Bean

SimpleMessageListenerContainer container(ConnectionFactory connectionFactory,

MessageListenerAdapter listenerAdapter) {

SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();

container.setConnectionFactory(connectionFactory);

container.setQueueNames(queueName);

container.setMessageListener(listenerAdapter);

return container;

}

@Bean

MessageListenerAdapter listenerAdapter(Receiver receiver) {

return new MessageListenerAdapter(receiver, "receiveMessage");

}

public static void main(String[] args) {

SpringApplication.run(SpringbootRabbitmqApplication.class, args);

}

创建一个测试方法：

@Component

public class Runner implements CommandLineRunner {

private final RabbitTemplate rabbitTemplate;

private final Receiver receiver;

private final ConfigurableApplicationContext context;

public Runner(Receiver receiver, RabbitTemplate rabbitTemplate,

ConfigurableApplicationContext context) {

this.receiver = receiver;

this.rabbitTemplate = rabbitTemplate;

this.context = context;

}

@Override

public void run(String... args) throws Exception {

System.out.println("Sending message...");

rabbitTemplate.convertAndSend(Application.queueName, "Hello from RabbitMQ!");

receiver.getLatch().await(10000, TimeUnit.MILLISECONDS);

context.close();

}

启动程序，你会发现控制台打印：

1 2	`Sending message...` `Received <Hello from RabbitMQ!>`