Java使用RabbitMQ发送和接收消息

红太狼 2021-07-24 18:04 432阅读 0赞

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：

<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：**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3Bhbl9qdW5iaWFv_size_16_color_FFFFFF_t_70][]

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