《RabbitMQ篇》消费者轮询消费消息

news2024/10/11 16:56:55

当有多个消费者都在同一个队列中拿取消息时，会轮询从队列中拿取消息消费。

RabbitMQUtil类为工具类，获取Channel。

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

public class RabbitMQUtil {
    public static Channel getChannel() throws Exception {
        //得到工厂
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        factory.setUsername("guest");
        factory.setPassword("guest");
        //生成连接
        Connection connection = factory.newConnection();
        //获取信道
        return connection.createChannel();
    }
}

创建一个生产者，并启动

import com.rabbitmq.client.Channel;

import java.util.Scanner;

public class Producer {
    private final static String QUEUE_NAME = "hello";

    public static void main(String[] args) throws Exception {
        Channel channel = RabbitMQUtil.getChannel();
        channel.queueDeclare(QUEUE_NAME, false, false, false, null);
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String message = sc.next();
            channel.basicPublish("", QUEUE_NAME, null, message.getBytes());
        }
    }
}

创建两个消费者，并启动

import com.rabbitmq.client.CancelCallback;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;

public class Consumer1 {
    private final static String QUEUE_NAME = "hello";

    public static void main(String[] args) throws Exception {
        Channel channel = RabbitMQUtil.getChannel();
        DeliverCallback deliverCallback = (consumerTag, message) -> {
            System.out.println("接收到信息：" + new String(message.getBody()));
        };
        CancelCallback cancelCallback = consumerTag -> {
            System.out.println("消息消费被中断");
        };
        System.out.println("C1消费者启动等待消费......");
        channel.basicConsume(QUEUE_NAME, true, deliverCallback, cancelCallback);
    }
}

import com.rabbitmq.client.CancelCallback;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DeliverCallback;

public class Consumer2 {
    private final static String QUEUE_NAME = "hello";

    public static void main(String[] args) throws Exception {
        Channel channel = RabbitMQUtil.getChannel();
        DeliverCallback deliverCallback = (consumerTag, message) -> {
            System.out.println("接收到信息：" + new String(message.getBody()));
        };
        CancelCallback cancelCallback = consumerTag -> {
            System.out.println("消息消费被中断");
        };
        System.out.println("C2消费者启动等待消费......");
        channel.basicConsume(QUEUE_NAME, true, deliverCallback, cancelCallback);
    }
}