RabbitMQ高级特性-Return消息机制

Return消息机制

• Return Listener用于处理一些不可路由的消息

• 正常情况下消息生产者通过指定一个Exchange和RoutingKey, 把消息送到某一个队列中去, 然后消费者监听队列, 进行消费

• 但在某些情况下, 如果在发送消息的时候, 当前的exchange不存在或者指定的路由key路由不到, 这个时候如果我们需要监听这种不可达的消息, 就要使用Return Listener

• 在基础API中有一个关键的配置项Mandatory : 如果为true, 则监听器会接收到路由不可达的消息, 然后进行后续处理, 如果为false, 那么broker端自动删除该消息

  

代码演示

Producer

package com.qiyexue.returnlistener;

import com.rabbitmq.client.*;

/**
 * Return Listener模式生产者
 *
 * @author 七夜雪
 * @create 2018-12-15 19:56
 */
public class Producer {

    public static void main(String[] args) throws Exception {
        // 1. 创建ConnectionFactory, 并设置属性
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("192.168.72.138");
        factory.setPort(5672);
        factory.setVirtualHost("/");

        // 2. 创建连接
        Connection connection = factory.newConnection();

        // 3. 创建channel
        Channel channel = connection.createChannel();

        // 4. 设置Return Listener监听
        channel.addReturnListener(new ReturnListener() {
            public void handleReturn(int replyCode, String replyText, String exchange, String routingKey, AMQP.BasicProperties properties, byte[] body) throws IOException {
                System.out.println("--------------Return Listener--------------");
                System.out.println(replyCode);
                System.out.println(replyText);
                System.out.println(exchange);
                System.out.println(routingKey);
                System.out.println(properties);
                System.out.println(new String(body));
            }
        });

        String exchangeName = "test_return_exchange";
        String routingKey = "return.qiye";
        String routingErrorKey = "error.qiye";

        // 发送消息
        String msg = "Send Msg And Return Listener By RoutingKey : ";
        channel.basicPublish(exchangeName, routingKey, true, null, (msg + routingKey).getBytes());
        channel.basicPublish(exchangeName, routingErrorKey,true, null, (msg + routingErrorKey).getBytes());

    }

}

Consumer

package com.qiyexue.returnlistener;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.QueueingConsumer;

/**
 * Return Listener模式消费者
 *
 * @author 七夜雪
 * @create 2018-12-15 20:07
 */
public class Consumer {

    public static void main(String[] args) throws Exception {
        // 1. 创建连接工厂并设置属性
        ConnectionFactory factory = new ConnectionFactory();;
        factory.setHost("192.168.72.138");
        factory.setPort(5672);
        factory.setVirtualHost("/");

        // 2. 创建连接
        Connection connection = factory.newConnection();

        // 3. 创建channel
        Channel channel = connection.createChannel();

        // 4. 声明Exchange
        String exchangeName = "test_return_exchange";
        String exchangeType = "topic";
        String routingKey = "return.*";
        channel.exchangeDeclare(exchangeName, exchangeType, true, false, null);

        // 5. 声明消息队列
        String queueName = "test_return_queue";
        channel.queueDeclare(queueName, true, false, false, null);

        // 6. 绑定队列和Exchange
        channel.queueBind(queueName, exchangeName, routingKey);

        // 7. 创建一个消费者
        QueueingConsumer consumer = new QueueingConsumer(channel);

        // 8. 设置消费者从哪个队列开始消费, 设置自动ACK
        channel.basicConsume(queueName, true, consumer);

        while (true) {
            QueueingConsumer.Delivery delivery = consumer.nextDelivery();
            String msg = new String(delivery.getBody());
            System.out.println(msg);
        }

    }

}

相关链接

RabbitMQ入门与AMQP协议简介
RabbitMQ成员简介
RabbitMQ高级特性-消息可靠性投递
RabbitMQ高级特性-幂等性保障
RabbitMQ高级特性-Confirm确认消息
RabbitMQ高级特性-Return消息机制
RabbitMQ高级特性-消费端自定义监听
RabbitMQ高级特性-消费端限流
RabbitMQ高级特性-消费端ACK与重回队列
RabbitMQ高级特性-TTL队列/消息
RabbitMQ高级特性-死信队列(DLX)
Spring AMQP整合RabbitMQ
SpringBoot整合RabbitMQ
RabbitMQ集群架构模式介绍
从零开始搭建高可用RabbitMQ镜像模式集群
RabbitMQ集群恢复与故障转移
RabbitMQ-基础组件封装
Git代码地址

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