注意事项:
1.队列设置优先级 权制范围(0-255)推荐0-10 否则浪费CPU与内存
2.发消息时给消息设置优先级
3.消息需要完全事先在队列中,在被消费者消费 会被排序,否则边生产边消费不会达到预期的队列优先效果。
优先级队列:
0-255越大越优先
推荐:0-10 CPU性能友好
先生产者生产消息:
package com.esint.rabbitmq.work07;import com.esint.rabbitmq.RabbitMQUtils;
import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.Channel;import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;public class Producer {public static final String QUEUE_NAME = "hello";public static void main(String[] args) throws Exception {Channel channel = RabbitMQUtils.getChannel();Map<String, Object> arguments = new HashMap<>();//队列设置优先即参数范围arguments.put("x-max-priority",10);//官方允许0-255 此处设置10 允许优先级范围 0-10 不设置过大 浪费CPU和内存channel.queueDeclare(QUEUE_NAME,false,false,false,arguments);//注意上面要求的 需要事先 发送完毕消息 才能体显现优先级的消息优化排序for (int i = 0; i < 10; i++) {String message = "msssage" + i;if(i == 3 ){//本实验的核心操作再次 在这里构建优先级设置参数 设置这个优先级的值需要在前面设置对立参数范围内AMQP.BasicProperties properties = new AMQP.BasicProperties().builder().priority(5).build();channel.basicPublish("",QUEUE_NAME,properties,message.getBytes(StandardCharsets.UTF_8));}else{channel.basicPublish("",QUEUE_NAME,null,message.getBytes(StandardCharsets.UTF_8));}}}
}
消费者消费消息:
package com.esint.rabbitmq.work07;import com.esint.rabbitmq.RabbitMQUtils;
import com.rabbitmq.client.CancelCallback;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;
import com.rabbitmq.client.Delivery;public class Comsumer {public static final String QUEUE_NAME = "hello";public static void main(String[] args) throws Exception {Channel channel = RabbitMQUtils.getChannel();DeliverCallback deliverCallback = ( consumerTag, message)->{System.out.println(new String(message.getBody(),"UTF-8"));};CancelCallback cancelCallback = (consumerTag)->{};channel.basicConsume(QUEUE_NAME,true,deliverCallback,cancelCallback);}
}
用到的工具类:
package com.esint.rabbitmq;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;public class RabbitMQUtils {public static Channel getChannel()throws Exception{//创建链接工厂ConnectionFactory connectionFactory = new ConnectionFactory();//设置链接connectionFactory.setHost("192.168.43.37");connectionFactory.setUsername("admin");connectionFactory.setPassword("admin");//链接工厂创建链接Connection connection = connectionFactory.newConnection();//获取信道Channel channel = connection.createChannel();return channel;}public static final void Sleep(int nums) {try {Thread.sleep(nums * 1000);}catch (InterruptedException _ignored){Thread.currentThread().interrupt();}}
}
产生的结果:
Connected to the target VM, address: '127.0.0.1:59793', transport: 'socket'
msssage3
msssage0
msssage1
msssage2
msssage4
msssage5
msssage6
msssage7
msssage8
msssage9