Java使用RabbitMQ发送和接收消息

RabbitMQ 是采用 Erlang 语言实现 AMQP（Advanced Message Queuing Protocol，高级消息队列协议）的消息中间件，它最初起源于金融系统，用于在分布式系统中存储转发消息。RabbitMQ 凭借其高可靠、易扩展、高可用及丰富的功能特性收到越来越多企业的青睐。下面介绍 Java 中如何使用 RabbitMQ 发送和接收消息。

使用Maven添加依赖文件

在pom.xml配置信息文件中，添加 RabbitMQ 客户端依赖：

<!-- RabbitMQ客户端 -->
<dependency>
    <groupId>com.rabbitmq</groupId>
    <artifactId>amqp-client</artifactId>
    <version>5.10.0</version>
</dependency>

1、发送者客户端代码

首先发送者发送一条消息至 RabbitMQ 中，之后由接收者消费。下面是发送者客户端代码：

package com.pjb.demo;

import com.rabbitmq.client.*;
import java.io.IOException;
import java.util.concurrent.TimeoutException;

/**
 * 发送者客户端
 * @author pan_junbiao
 **/
public class RabbitProducer
{
    private static final String EXCHANGE_NAME = "exchange_demo";
    private static final String ROUTING_KEY = "routingkey_demo";
    private static final String QUEUE_NAME = "queue_demo";
    private static final String IP_ADDRESS = "127.0.0.1";
    private static final int PORT = 5672; //RabbitMQ 服务端默认端口号为 5672
    private static final String USER_NAME = "guest";
    private static final String PASSWORD = "guest";

    public static void main(String[] args) throws IOException, TimeoutException
    {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost(IP_ADDRESS);
        factory.setPort(PORT);
        factory.setUsername(USER_NAME);
        factory.setPassword(PASSWORD);
        Connection connection = factory.newConnection(); //创建连接
        Channel channel = connection.createChannel(); //创建信道
        //创建一个 type = DIRECT、持久化的、非自动删除的交换器
        channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT, true, false, null);
        //创建一个持久化、非排他的、非自动删除的队列
        channel.queueDeclare(QUEUE_NAME,true,false,false,null);
        //将交换器与队列通过路由键绑定
        channel.queueBind(QUEUE_NAME,EXCHANGE_NAME,ROUTING_KEY);
        //发送一条持久化的信息
        String message = "您好，欢迎访问 pan_junbiao的博客";
        channel.basicPublish(EXCHANGE_NAME,ROUTING_KEY, MessageProperties.PERSISTENT_TEXT_PLAIN,message.getBytes());
        //关闭资源
        channel.close();
        connection.close();
    }
}

2、接收者客户端代码

这里采用继承 DefaultConsumer 的方式来实现接收者。下面是接收者客户端代码：

package com.pjb.demo;

import com.rabbitmq.client.*;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * 接收者客户端
 * @author pan_junbiao
 **/
public class RabbitConsumer
{
    private static final String QUEUE_NAME = "queue_demo";
    private static final String IP_ADDRESS = "127.0.0.1";
    private static final int PORT = 5672; //RabbitMQ 服务端默认端口号为 5672
    private static final String USER_NAME = "guest";
    private static final String PASSWORD = "guest";

    public static void main(String[] args) throws IOException, TimeoutException,InterruptedException
    {
        Address[] addresses = new Address[]{new Address(IP_ADDRESS, PORT)};
        ConnectionFactory factory = new ConnectionFactory();
        factory.setUsername(USER_NAME);
        factory.setPassword(PASSWORD);
        Connection connection = factory.newConnection(addresses); //创建连接
        final Channel channel = connection.createChannel(); //创建信道
        channel.basicQos(64); //设置客户端最多接收未被ack的消息的个数
        Consumer consumer = new DefaultConsumer(channel)
        {
            @Override
            public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException
            {
                System.out.println("接收信息：" + new String(body));
                try
                {
                    TimeUnit.SECONDS.sleep(1);
                }
                catch (InterruptedException ie)
                {
                    ie.printStackTrace();
                }
                channel.basicAck(envelope.getDeliveryTag(), false);
            }
        };
        channel.basicConsume(QUEUE_NAME, consumer);
        //等待回调函数执行完毕之后，关闭资源
        TimeUnit.SECONDS.sleep(5);
        channel.close();
        connection.close();
    }
}

执行结果：