6、RabbitMQ-路由模式

Exchange(交换机 转换器）

Exchange分发消息时根据类型的不同分发策略有区别，

目前共四种类型：direct、fanout、topic、headers 。

 

一方面是接受生产者的消息，一方面是向队列推送消息

 

basicPublish(String exchange, String routingKey, BasicProperties props, byte[] body) throws IOException

queueBind(String queue, String exchange, String routingKey) throws IOException

“”匿名转发

 

fanout：不处理路由键

每个发到 fanout 类型交换器的消息都会分到所有绑定的队列上去。fanout 交换器不处理路由键，

只是简单的将队列绑定到交换器上，每个发送到交换器的消息都会被转发到与该交换器绑定的所有

队列上。很像子网广播，每台子网内的主机都获得了一份复制的消息。fanout 类型转发消

息是最快的。

direct：

消息中的路由键（routing key）如果和 Binding 中的 binding key 一致，

 交换器就将消息发到对应的队列中。路由键与队列名完全匹配，

如果一个队列绑定到交换机要求路由键为“dog”，则只转发 routing key

 标记为“dog”的消息，不会转发“dog.puppy”，也不会转发“dog.guard”等等。

它是完全匹配、单播的模式

 

topic：

topic 交换器通过模式匹配分配消息的路由键属性，将路由键和某个模式进行匹配，此时队列需要绑

定到一个模式上。它将路由键和绑定键的字符串切分成单词，这些单词之间用点隔开。它同样也会识

别两个通配符：符号“#”和符号“*”。#匹配0个或多个单词，*匹配一个单词

 

 路由模式

 http://www.rabbitmq.com/tutorials/tutorial-four-java.html

 1、模型

 

2、代码实践

 生产者

import java.io.IOException;
import java.util.concurrent.TimeoutException;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.util.ConnectionUtils;
public class Send {
     
     private static final String EXCHANGE_NAME =  "exchange_routing_direct";
     
     public static void main(String[] args) throws IOException,  TimeoutException {
           
           Connection conn = ConnectionUtils.getConnection();
           Channel channel = conn.createChannel();
           
           //exchange
           channel.exchangeDeclare(EXCHANGE_NAME, "direct");
           
           String msg = "hello direct";
           
           //绑定路由
           String routingKey = "error";
           channel.basicPublish(EXCHANGE_NAME, routingKey, null,  msg.getBytes());
           
           channel.close();
           conn.close();
     }
}

消费者1：

import java.io.IOException;
import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Consumer;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;
import com.rabbitmq.client.AMQP.BasicProperties;
import com.rabbitmq.util.ConnectionUtils;

public class Receive {
    
    private static final String QUEUE_NAME="test_route";
    private static final String EXCHANGE_NAME = "exchange_routing_direct";
    
    public static void main(String[] args) throws IOException, TimeoutException {
        
        Connection conn = ConnectionUtils.getConnection();
        
        Channel channel = conn.createChannel();
        
        //队列声明
        channel.queueDeclare(QUEUE_NAME, false, false, false, null);
        
        channel.basicQos(1);
        
        //绑定队列到交换机转发器
        String routingKey = "error";
        channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, routingKey);

                //定义一个消费者
                Consumer consumer = new DefaultConsumer(channel){
                    //收到消息就会触发这个方法
                    @Override
                    public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body)
                            throws IOException {
                        String msg = new String(body,"utf-8");
                        System.out.println("消费者1接收到的消息" + msg);
                        
                        try {
                            Thread.sleep(1500);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }finally{
                            System.out.println("消费者1处理完成！");
                            //手动回执
                            channel.basicAck(envelope.getDeliveryTag(), false);
                        }
                    }
                };
                //监听队列
                //自动应答false
                boolean autoAck = false;
                channel.basicConsume(QUEUE_NAME, autoAck, consumer);
    }
}

消费者2：

import java.io.IOException;
import java.util.concurrent.TimeoutException;

import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.Consumer;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;
import com.rabbitmq.client.AMQP.BasicProperties;
import com.rabbitmq.util.ConnectionUtils;

public class Receive2 {
    
    private static final String QUEUE_NAME="test_queue";
    private static final String EXCHANGE_NAME = "exchange_routing_direct";
    
    public static void main(String[] args) throws IOException, TimeoutException {
        
        Connection conn = ConnectionUtils.getConnection();
        
        Channel channel = conn.createChannel();
        
        //队列声明
        channel.queueDeclare(QUEUE_NAME, false, false, false, null);
        
        channel.basicQos(1);
        
        //绑定队列到交换机转发器
        //可以同时绑定多个
        channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "error");
        channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "info");
        channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "warning");
        
                //定义一个消费者
                Consumer consumer = new DefaultConsumer(channel){
                    //收到消息就会触发这个方法
                    @Override
                    public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body)
                            throws IOException {
                        String msg = new String(body,"utf-8");
                        System.out.println("消费者2接收到的消息" + msg);
                        
                        try {
                            Thread.sleep(1500);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }finally{
                            System.out.println("消费者2处理完成！");
                            //手动回执
                            channel.basicAck(envelope.getDeliveryTag(), false);
                        }
                    }
                };
                //监听队列
                //自动应答false
                boolean autoAck = false;
                channel.basicConsume(QUEUE_NAME, autoAck, consumer);
    }
}

此时的测试只有在error的情况下两者均可收到信息

在其他的模式下只有消费者2可以获取消息