rabbitmq学习记录（五）交换机Exchange-fanout

之前学习的都是一条消息发给一个消费者，下面开始记录如何把一条信息发给多个消费者

这边我们用到了交换机Exchange

交换机模式：fanout

模式特点：生产者把消息发送给Exchange之后，Exchange则会把这些消息添加到与自己绑定的所有队列之中，监听这些队列的消费者就可以收到这些消息。

注：Exchange并不能保存信息，如果没有绑定的队列，那么生产者发送数据就会丢失，只有队列才能存储生产者的消息。

生产者：声明交换机后指定交换机模式fanout

package com.example.demo.queue.exchangeToQueue.fanout;

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

import com.example.demo.utils.ConnectionUtil;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;

public class Producer {

	// exchange名称
	private static final String EXCHANGE_NAME = "exchange_fanout"; 
	
	public static void main(String[] args) {
		Connection connection = null;
		Channel channel = null;
		try {
			// 获取连接
			connection = ConnectionUtil.getConnection();
			// 创建通道
			channel = connection.createChannel();
			// 声明交换机
			channel.exchangeDeclare(EXCHANGE_NAME, "fanout", true);
			// 生产者发送的信息
			String msg = "msg from producer:";
			for(int i=0;i<10;i++) {
				msg = "msg from producer :" + i;
				System.out.println("send msg : "+msg);
				// 发送信息
				channel.basicPublish(EXCHANGE_NAME, "", null, msg.getBytes());
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			// 关闭通道
			try {
				channel.close();
			} catch (IOException e) {
				e.printStackTrace();
			} catch (TimeoutException e) {
				e.printStackTrace();
			}
			// 关闭连接
			try {
				connection.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		
	}
	
}

消费者1：声明队列fanout_exchange_to_queue_01并绑定到交换机exchange_fanout

package com.example.demo.queue.exchangeToQueue.fanout;

import java.io.IOException;

import com.example.demo.utils.ConnectionUtil;
import com.rabbitmq.client.AMQP.BasicProperties;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

public class Consumer01 {

	// 交换机名称
	private static final String EXCHANGE_NAME = "exchange_fanout"; 
	
	// 监听队列名称
	private static final String QUEUE_NAME = "fanout_exchange_to_queue_01";
	
	public static void main(String[] args) {
		try {
			// 获取连接
			Connection connection = ConnectionUtil.getConnection();
			// 创建通道
			final Channel channel = connection.createChannel();
			// 声明队列
			channel.queueDeclare(QUEUE_NAME, true, false, false, null);
			// 绑定队列到交换机
			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "");
			// 定义消费者
			DefaultConsumer consumer = new DefaultConsumer(channel) {
				@Override
				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {
					String msg = new String(body,"UTF-8");
					System.out.println("[1]:receive msg:"+msg);
					System.out.println("[1]:deal msg successful.");
				}
				
			};
			// 接收信息
			channel.basicConsume(QUEUE_NAME, true, consumer);
			
			
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
}

消费者2：声明队列fanout_exchange_to_queue_02并绑定到交换机exchange_fanout

package com.example.demo.queue.exchangeToQueue.fanout;

import java.io.IOException;

import com.example.demo.utils.ConnectionUtil;
import com.rabbitmq.client.AMQP.BasicProperties;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

public class Consumer02 {

	// 交换机名称
	private static final String EXCHANGE_NAME = "exchange_fanout"; 
	
	// 监听队列名称
	private static final String QUEUE_NAME = "fanout_exchange_to_queue_02";
	
	public static void main(String[] args) {
		try {
			// 获取连接
			Connection connection = ConnectionUtil.getConnection();
			// 创建通道
			final Channel channel = connection.createChannel();
			// 声明队列
			channel.queueDeclare(QUEUE_NAME, true, false, false, null);
			// 绑定队列到交换机
			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "");
			// 定义消费者
			DefaultConsumer consumer = new DefaultConsumer(channel) {
				@Override
				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {
					String msg = new String(body,"UTF-8");
					System.out.println("[2]:receive msg:"+msg);
					System.out.println("[2]:deal msg successful.");
				}
			};
			// 接收信息
			channel.basicConsume(QUEUE_NAME, true, consumer);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
}

消费者3：声明队列fanout_exchange_to_queue_03，没有绑定到交换机exchange_fanout

package com.example.demo.queue.exchangeToQueue.fanout;

import java.io.IOException;

import com.example.demo.utils.ConnectionUtil;
import com.rabbitmq.client.AMQP.BasicProperties;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

public class Consumer03 {

	// 交换机名称
	private static final String EXCHANGE_NAME = "exchange_fanout"; 
	
	// 监听队列名称
	private static final String QUEUE_NAME = "fanout_exchange_to_queue_03";
	
	public static void main(String[] args) {
		try {
			// 获取连接
			Connection connection = ConnectionUtil.getConnection();
			// 创建通道
			final Channel channel = connection.createChannel();
			// 声明队列
			channel.queueDeclare(QUEUE_NAME, true, false, false, null);
			// 绑定队列到交换机
//			channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "");
			// 定义消费者
			DefaultConsumer consumer = new DefaultConsumer(channel) {
				@Override
				public void handleDelivery(String consumerTag, Envelope envelope, BasicProperties properties, byte[] body) throws IOException {
					String msg = new String(body,"UTF-8");
					System.out.println("[3]:receive msg:"+msg);
					System.out.println("[3]:deal msg successful.");
				}
			};
			// 接收信息
			channel.basicConsume(QUEUE_NAME, true, consumer);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
}

这次，涉及到了交换机，而在消费者类中中并没有声明交换机，所以需要先执行生产者类的main方法