1.Direct

直连(路由)交换机,生产者将消息发送到交换机，并指定消息的Routing Key（路由键）。交换机会将Routing Key与队列绑定进行匹配，如果匹配成功，则将该消息路由到对应的队列中。如果没有匹配成功，该消息将被丢弃或返回给生产者。在Direct模式中，每个消息只能被一个消费者接收。
通过使用Exchange和Routing Key来进行消息传输，Direct模式实现了消息的有选择性地路由，提高了消息传输的效率，减少了系统负载.


如上图中的routingKey为error绑定队列disk,routingKey为info或warning绑定队列console。

2.生产者

package com.hong.rabbitmq7;import com.hong.utils.RabbitMQUtil;
import com.rabbitmq.client.BuiltinExchangeType;
import com.rabbitmq.client.Channel;import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;/*** @Description: 直连模式消息发送者* @Author: hong* @Date: 2024-01-15 22:24* @Version: 1.0**/
public class DirectSend {public static final String EXCHANGE_NAME = "direct_logs";public static void main(String[] args) throws Exception {Channel channel = RabbitMQUtil.getChannel();channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT);Map<String,String> map = new HashMap<>();map.put("info","我是info信息");map.put("debug","我是debug信息");map.put("warning","我是warning信息");map.put("error","我是error信息");for(Map.Entry<String,String> bindingKeys : map.entrySet()){String bindingKey = bindingKeys.getKey();String message = bindingKeys.getValue();channel.basicPublish(EXCHANGE_NAME,bindingKey,null,message.getBytes(StandardCharsets.UTF_8));System.out.println("消息发送完成------" + message);}}
}

3.消费者1-disk只接受error消息

package com.hong.rabbitmq7;import com.hong.utils.RabbitMQUtil;
import com.rabbitmq.client.BuiltinExchangeType;
import com.rabbitmq.client.CancelCallback;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;import java.nio.charset.StandardCharsets;/*** @Description: 直连模式消息接收者1-disk接收error消息* @Author: hong* @Date: 2024-01-15 20:22* @Version: 1.0**/
public class Receiver1 {public static final String EXCHANGE_NAME = "direct_logs";public static void main(String[] args) throws Exception {Channel channel = RabbitMQUtil.getChannel();/**声明交换机*第1个参数:交换机名称*第2个参数:交换机类型*/channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT);//声明队列String queueName = "disk";channel.queueDeclare(queueName,false,false,false,null);/** 绑定队列与交换机* 第1个参数:队列名称* 第2个参数:交换机名称* 第3个参数:routingKey*/channel.queueBind(queueName,EXCHANGE_NAME,"error");DeliverCallback deliverCallback = (comsumerTag, message) -> {System.out.println("disk中的:"+  new String(message.getBody(), StandardCharsets.UTF_8));};CancelCallback cancelCallback = var -> {};channel.basicConsume(queueName,true,deliverCallback,cancelCallback);}
}

4.消费2-console接收info和warning消息

package com.hong.rabbitmq7;import com.hong.utils.RabbitMQUtil;
import com.rabbitmq.client.BuiltinExchangeType;
import com.rabbitmq.client.CancelCallback;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;import java.nio.charset.StandardCharsets;/*** @Description: 直连模式消息接收者2-console接收info和warning消息* @Author: hong* @Date: 2024-01-15 20:22* @Version: 1.0**/
public class Receiver2 {public static final String EXCHANGE_NAME = "direct_logs";public static void main(String[] args) throws Exception {Channel channel = RabbitMQUtil.getChannel();/**声明交换机*第1个参数:交换机名称*第2个参数:交换机类型*/channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT);//声明队列String queueName = "console";channel.queueDeclare(queueName,false,false,false,null);/** 绑定队列与交换机* 第1个参数:队列名称* 第2个参数:交换机名称* 第3个参数:routingKey*/channel.queueBind(queueName,EXCHANGE_NAME,"info");channel.queueBind(queueName,EXCHANGE_NAME,"warning");DeliverCallback deliverCallback = (comsumerTag, message) -> {System.out.println("console中的:"+  new String(message.getBody(), StandardCharsets.UTF_8));};CancelCallback cancelCallback = var -> {};channel.basicConsume(queueName,true,deliverCallback,cancelCallback);}
}