メッセージモード2 rabiitmq

消費者側の制限

何が消費者側を制限していますか？

まず、我々はRabbitMQの、シーンを想定1万を介してサーバ未処理のメッセージを、私たちは消費者のクライアントを開いて、以下の条件を表示されます。

すべてのプッシュオーバーのインスタントメッセージの膨大な量は、しかし、我々は、単一のクライアントが同時にので、多くのデータを扱うことができない持っています！

制限消費者エンドのRabbitMQ 提供ソリューション

RabbitMQのは提供したQoS （サービス品質）を備えてい、すなわち非自動受信確認メッセージを、メッセージの特定の数ならばという前提の下（もとを通じて消費者やチャンネルた設定QoSが前に確認されていない、新しいニュースの消費値）

ボイドBasicQos（UINT PREFETCHSIZE、USHORT prefetchCount、BOOLグローバル）。

PREFETCHSIZE ：0は、メッセージのサイズを制限しません

PREFETCHSIZE ：「言うでしょRabbitMQのより多くの消費者にプッシュしていないが、N個の一回という、メッセージNのメッセージはしていないACK 、消費者がしますブロックのメッセージまでオフ（遮断）ACK

Global：true\false是否将上面设置应用于Channel；简单来说，就是上面限制是Channel级别的还是Consumer级别

 

注意：

 

　　prefetchSize和global这两项，RabbitMQ没有实现，暂且不研究；

 

　　prefetch_count在no_ask=false的情况下生效，即在自动应答的情况下，这两个值是不生效的；

 

 

自定义消费端代码

 

 

package com.huang.rabbitmqapi.limit;

import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

import java.io.IOException;

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 16:13
 */
public class MyConsumer extends DefaultConsumer {
    private Channel channel ;

    public MyConsumer(Channel channel) {
        super(channel);
        this.channel = channel;
    }

    @Override
    public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
        System.err.println("-----------consume message----------");
        System.err.println("consumerTag: " + consumerTag);
        System.err.println("envelope: " + envelope);
        System.err.println("properties: " + properties);
        System.err.println("body: " + new String(body));

        channel.basicAck(envelope.getDeliveryTag(), false);
    }

}

 

消费端代码

 

 

package com.huang.rabbitmqapi.limit;

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

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 16:17
 */
public class Consumer {
    public static void main(String[] args) throws Exception {
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        Connection connection = connectionFactory.newConnection();
        Channel channel = connection.createChannel();


        String exchangeName = "test_qos_exchange";
        String queueName = "test_qos_queue";
        String routingKey = "qos.#";

        channel.exchangeDeclare(exchangeName, "topic", true, false, null);
        channel.queueDeclare(queueName, true, false, false, null);
        channel.queueBind(queueName, exchangeName, routingKey);

        //1 限流方式  第一件事就是 autoAck设置为 false
        channel.basicQos(0, 1, false);

        channel.basicConsume(queueName, false, new MyConsumer(channel));
    }
}

 

提供方代码

 

 

package com.huang.rabbitmqapi.limit;

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

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:00
 */
public class Producer {
    public static void main(String[] args) throws Exception {
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        Connection connection = connectionFactory.newConnection();
        Channel channel = connection.createChannel();

        String exchange = "test_qos_exchange";
        String routingKey = "qos.save";

        String msg = "Hello RabbitMQ QOS Message";

        for(int i =0; i<5; i ++){
            channel.basicPublish(exchange, routingKey, true, null, msg.getBytes());
        }

    }
}

 

消息的ACK与重回队列

 

 

消费端手工ACK与NACK

 

消费端进行消费的时候，如果由于业务异常我们可以进行日志的记录，然后进行补偿

 

如果由于服务器宕机等严重问题，那么我们就需要手工进行ACK，保障消费端消费成功！

 

消费端的重回队列

 

消费端重回队列是为了对没有处理成功的消息，把消息重新回递给Broker！

 

一般我们在实际应用中，都会关闭重回队列，也就是设置为False；因为重回队列消息有很大概率依然会处理失败！

 

自定义消费者代码

package com.huang.rabbitmqapi.ack;

import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

import java.io.IOException;

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:03
 */
public class MyConsumer extends DefaultConsumer {


    private Channel channel ;

    public MyConsumer(Channel channel) {
        super(channel);
        this.channel = channel;
    }

    @Override
    public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
        System.err.println("-----------consume message----------");
        System.err.println("body: " + new String(body));
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        if((Integer)properties.getHeaders().get("num") == 0) {
//            手动签收，重回队列
            channel.basicNack(envelope.getDeliveryTag(), false, true);
        } else {
            channel.basicAck(envelope.getDeliveryTag(), false);
        }

    }


}

消费者代码

 

 

package com.huang.rabbitmqapi.ack;

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

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:05
 */
public class Consumer {
    public static void main(String[] args) throws Exception {
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        Connection connection = connectionFactory.newConnection();
        Channel channel = connection.createChannel();


        String exchangeName = "test_ack_exchange";
        String queueName = "test_ack_queue";
        String routingKey = "ack.#";

        channel.exchangeDeclare(exchangeName, "topic", true, false, null);
        channel.queueDeclare(queueName, true, false, false, null);
        channel.queueBind(queueName, exchangeName, routingKey);

        // 手工签收 必须要关闭 autoAck = false
        channel.basicConsume(queueName, false, new MyConsumer(channel));
    }
}

 

生产者代码

 

 

package com.huang.rabbitmqapi.ack;

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

import java.util.HashMap;
import java.util.Map;

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:07
 */
    public class Producer {
    public static void main(String[] args) throws Exception {
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        Connection connection = connectionFactory.newConnection();
        Channel channel = connection.createChannel();

        String exchange = "test_ack_exchange";
        String routingKey = "ack.save";

        for(int i =0; i<5; i ++){
            Map<String, Object> headers = new HashMap<String, Object>();
            headers.put("num", i);
            AMQP.BasicProperties properties = new AMQP.BasicProperties.Builder()
                    .deliveryMode(2)
                    .contentEncoding("UTF-8")
                    .headers(headers)
                    .build();
            String msg = "Hello RabbitMQ ACK Message " + i;
            channel.basicPublish(exchange, routingKey, true, properties, msg.getBytes());
        }
    }
}

 

TTL消息

TTL是Time To Live的缩写，也就是生存时间

RabbitMQ支持消息的过期时间，在消息发送时可以进行指定

RabbitMQ支持队列的过期时间，从消息入队列开始计算，只要超过了队列的超时时间配置，那么消息自动的清除

纯控制台操作（演示TTL队列消息特点）

针对队列，只要是这个队列的消息，就只有这么长的存活时间

注意：主要针对消息设置，跟交换机、队列、消费者设置毫无关系

 

 

消费端代码

package com.huang.rabbitmqapi.ttl;

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

import java.util.Map;

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:05
 */
public class Consumer {
    public static void main(String[] args) throws Exception {

        //1 创建一个ConnectionFactory, 并进行配置
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        //2 通过连接工厂创建连接
        Connection connection = connectionFactory.newConnection();

        //3 通过connection创建一个Channel
        Channel channel = connection.createChannel();

        //4 声明（创建）一个队列
        String queueName = "test001";
        channel.queueDeclare(queueName, true, false, false, null);

        //5 创建消费者
        QueueingConsumer queueingConsumer = new QueueingConsumer(channel);

        //6 设置Channel
        channel.basicConsume(queueName, true, queueingConsumer);

        while(true){
            //7 获取消息
            QueueingConsumer.Delivery delivery = queueingConsumer.nextDelivery();
            String msg = new String(delivery.getBody());
            System.err.println("消费端: " + msg);
            Map<String, Object> headers = delivery.getProperties().getHeaders();
            System.err.println("headers get my1 value: " + headers.get("my1"));

            //Envelope envelope = delivery.getEnvelope();
        }

    }
}

生产端代码

package com.huang.rabbitmqapi.ttl;

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

import java.util.HashMap;
import java.util.Map;

/**
 * @auther 宇晨
 * @site www.cnblogs.com/bf6rc9qu/
 * @company
 * @create 2019-12-28 17:05
 */
public class Procuder {
    public static void main(String[] args) throws Exception {
        //1 创建一个ConnectionFactory, 并进行配置
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("192.168.188.131");
        connectionFactory.setPort(5672);
        connectionFactory.setVirtualHost("/");

        //2 通过连接工厂创建连接
        Connection connection = connectionFactory.newConnection();

        //3 通过connection创建一个Channel
        Channel channel = connection.createChannel();

        Map<String, Object> headers = new HashMap<>();
        headers.put("my1", "111");
        headers.put("my2", "222");


        AMQP.BasicProperties properties = new AMQP.BasicProperties.Builder()
                .deliveryMode(2)
                .contentEncoding("UTF-8")
                .expiration("10000")
                .headers(headers)
                .build();

        //4 通过Channel发送数据
        for(int i=0; i < 5; i++){
            String msg = "Hello RabbitMQ!";
            //1 exchange   2 routingKey
            channel.basicPublish("", "test001", properties, msg.getBytes());
        }

        //5 记得要关闭相关的连接
        channel.close();
        connection.close();
    }
}