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RabbitMQ的5种消息队列

1、七种模式介绍与应用场景

1.1 简单模式(Hello World)

一个生产者对应一个消费者，RabbitMQ 相当于一个消息代理，负责将 A 的消息转发给 B。

应用场景：将发送的电子邮件放到消息队列，然后邮件服务在队列中获取邮件并发送给收件人。

1.2 工作队列模式(Work queues)

在多个消费者之间分配任务(竞争的消费者模式)，一个生产者对应多个消费者，一般适用于执行资源密集型任务，

单个消费者处理不过来，需要多个消费者进行处理。

应用场景：一个订单的处理需要10s，有多个订单可以同时放到消息队列，然后让多个消费者同时处理，这样就是

并行了，而不是单个消费者的串行情况。

1.3 订阅模式(Publish/Subscribe)

一次向许多消费者发送消息，一个生产者发送的消息会被多个消费者获取，也就是将消息将广播到所有的消费者

中。

应用场景：更新商品库存后需要通知多个缓存和多个数据库，这里的结构应该是：

• 一个 fanout 类型交换机扇出两个个消息队列，分别为缓存消息队列、数据库消息队列
• 一个缓存消息队列对应着多个缓存消费者
• 一个数据库消息队列对应着多个数据库消费者

1.4 路由模式(Routing)

有选择地 (Routing key) 接收消息，发送消息到交换机并且要指定路由 key，消费者将队列绑定到交换机时需要指

定路由 key，仅消费指定路由 key 的消息。

应用场景：如在商品库存中增加了 1 台 iphone12，iphone12 促销活动消费者指定 routing key 为 iphone12，只

有此促销活动会接收到消息，其它促销活动不关心也不会消费此 routing key 的消息。

1.5 主题模式(Topics)

根据主题 (Topics) 来接收消息，将路由 key 和某模式进行匹配，此时队列需要绑定在一个模式上，#匹配一个词

或多个词，*只匹配一个词。

应用场景：同上 iphone 促销活动可以接收主题为 iphone 的消息，如 iphone12、iphone13 等。

1.6 远程过程调用(RPC)

如果我们需要在远程计算机上运行功能并等待结果就可以使用 RPC，具体流程可以看图。

应用场景：需要等待接口返回数据，如订单支付。

1.7 发布者确认(Publisher Confirms)

与发布者进行可靠的发布确认，发布者确认是 RabbitMQ 扩展，可以实现可靠的发布。在通道上启用发布者确认

后，RabbitMQ 将异步确认发送者发布的消息，这意味着它们已在服务器端处理。

应用场景：对于消息可靠性要求较高，比如钱包扣款。

2、代码演示

<dependency><groupId>com.rabbitmq</groupId><artifactId>amqp-client</artifactId><version>5.6.0</version>
</dependency>

2.1 简单模式

package simple;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String QUEUE_NAME = "simple_queue";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 声明队列// queue: 队列名// durable: 是否持久化// exclusive: 是否排外,即只允许该channel访问该队列,一般等于true的话用于一个队列只能有一个消费者来消费的场景// autoDelete: 是否自动删除,消费完删除// arguments: 其他属性channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 消息内容String message = "simplest mode message";channel.basicPublish("", QUEUE_NAME, null, message.getBytes());System.out.println("[x]Sent '" + message + "'");// 最后关闭通关和连接channel.close();connection.close();}
}

package simple;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver {private final static String QUEUE_NAME = "simple_queue";public static void main(String[] args) throws IOException, TimeoutException {// 获取连接ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

[x]Sent 'simplest mode message'[x] Received 'simple_queue':'simplest mode message'

2.2 工作队列模式

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 同一时刻服务器只会发送一条消息给消费者channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 同一时刻服务器只会发送一条消息给消费者channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package work;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String QUEUE_NAME = "queue_work";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 声明队列channel.queueDeclare(QUEUE_NAME, false, false, false, null);for (int i = 0; i < 10; i++) {String message = "work mode message" + i;channel.basicPublish("", QUEUE_NAME, null, message.getBytes());System.out.println("[x] Sent '" + message + "'");Thread.sleep(i * 10);}channel.close();connection.close();}
}

[x] Sent 'work mode message0'
[x] Sent 'work mode message1'
[x] Sent 'work mode message2'
[x] Sent 'work mode message3'
[x] Sent 'work mode message4'
[x] Sent 'work mode message5'
[x] Sent 'work mode message6'
[x] Sent 'work mode message7'
[x] Sent 'work mode message8'
[x] Sent 'work mode message9'[x-1] Received 'queue_work':'work mode message0'
[x-1] Received 'queue_work':'work mode message2'
[x-1] Received 'queue_work':'work mode message4'
[x-1] Received 'queue_work':'work mode message6'
[x-1] Received 'queue_work':'work mode message8'[x-2] Received 'queue_work':'work mode message1'
[x-2] Received 'queue_work':'work mode message3'
[x-2] Received 'queue_work':'work mode message5'
[x-2] Received 'queue_work':'work mode message7'
[x-2] Received 'queue_work':'work mode message9'

2.3 发布订阅模式

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;public class Receive1 {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String queueName = channel.queueDeclare().getQueue();channel.queueBind(queueName, EXCHANGE_NAME, "");System.out.println(" [*] Waiting for messages. To exit press CTRL+C");// 订阅消息的回调函数DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + message + "'");};// 消费者，有消息时出发订阅回调函数channel.basicConsume(queueName, true, deliverCallback, consumerTag -> {});}
}

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;public class Receive2 {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String queueName = channel.queueDeclare().getQueue();channel.queueBind(queueName, EXCHANGE_NAME, "");System.out.println(" [*] Waiting for messages. To exit press CTRL+C");// 订阅消息的回调函数DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received2 '" + message + "'");};// 消费者，有消息时出发订阅回调函数channel.basicConsume(queueName, true, deliverCallback, consumerTag -> {});}
}

package publishsubscribe;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;public class Sender {private static final String EXCHANGE_NAME = "logs";public static void main(String[] argv) throws Exception {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, "fanout");String message = "publish subscribe message";channel.basicPublish(EXCHANGE_NAME, "", null, message.getBytes("UTF-8"));System.out.println(" [x] Sent '" + message + "'");channel.close();connection.close();}
}

[x] Sent 'publish subscribe message'[*] Waiting for messages. To exit press CTRL+C
[x-1] Received 'publish subscribe message'[*] Waiting for messages. To exit press CTRL+C
[x-2] Received2 'publish subscribe message'

2.4 路由模式

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_routing";private final static String EXCHANGE_NAME = "exchange_direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 指定路由的key,接收key和key2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key");channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key2");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_routing2";private final static String EXCHANGE_NAME = "exchange_direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 仅接收key2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key2");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" +delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package router;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String EXCHANGE_NAME = "exchange_direct";private final static String EXCHANGE_TYPE = "direct";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();// 交换机声明channel.exchangeDeclare(EXCHANGE_NAME, EXCHANGE_TYPE);// 只有routingKey相同的才会消费String message = "routing mode message";channel.basicPublish(EXCHANGE_NAME, "key2", null, message.getBytes());System.out.println("[x] Sent '" + message + "'");// channel.basicPublish(EXCHANGE_NAME, "key", null, message.getBytes());// System.out.println("[x] Sent '" + message + "'");channel.close();connection.close();}
}

[x] Sent 'routing mode message'[x-1] Received 'key2':'routing mode message'[x-2] Received 'key2':'routing mode message'

2.5 主题模式

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver1 {private final static String QUEUE_NAME = "queue_topic";private final static String EXCHANGE_NAME = "exchange_topic";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// 可以接收key.1channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "key.*");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-1] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.DeliverCallback;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Receiver2 {private final static String QUEUE_NAME = "queue_topic2";private final static String EXCHANGE_NAME = "exchange_topic";private final static String EXCHANGE_TYPE = "topic";public static void main(String[] args) throws IOException, InterruptedException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.queueDeclare(QUEUE_NAME, false, false, false, null);// *号代表单个单词，可以接收key.1channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "*.*");// #号代表多个单词，可以接收key.1.2channel.queueBind(QUEUE_NAME, EXCHANGE_NAME, "*.#");channel.basicQos(1);DeliverCallback deliverCallback = (consumerTag, delivery) -> {String message = new String(delivery.getBody(), "UTF-8");System.out.println(" [x-2] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");};channel.basicConsume(QUEUE_NAME, true, deliverCallback, consumerTag -> {});}
}

package topic;import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Connection;
import com.rabbitmq.client.ConnectionFactory;import java.io.IOException;
import java.util.concurrent.TimeoutException;public class Sender {private final static String EXCHANGE_NAME = "exchange_topic";private final static String EXCHANGE_TYPE = "topic";public static void main(String[] args) throws IOException, TimeoutException {ConnectionFactory factory = new ConnectionFactory();factory.setHost("localhost");factory.setPort(5672);Connection connection = factory.newConnection();Channel channel = connection.createChannel();channel.exchangeDeclare(EXCHANGE_NAME, EXCHANGE_TYPE);String message = "topics model message with key.1";channel.basicPublish(EXCHANGE_NAME, "key.1", null, message.getBytes());System.out.println("[x] Sent '" + message + "'");String message2 = "topics model message with key.1.2";channel.basicPublish(EXCHANGE_NAME, "key.1.2", null, message2.getBytes());System.out.println("[x] Sent '" + message2 + "'");channel.close();connection.close();}
}

[x] Sent 'topics model message with key.1'
[x] Sent 'topics model message with key.1.2'[x-1] Received 'key.1':'topics model message with key.1'[x-2] Received 'key.1':'topics model message with key.1'
[x-2] Received 'key.1.2':'topics model message with key.1.2'

3、四种交换机介绍

• 直连交换机( Direct exchange )：具有路由功能的交换机，绑定到此交换机的时候需要指定一个

  routing_key，交换机发送消息的时候需要 routing_key，会将消息发送道对应的队列。

• 扇形交换机( Fanout exchange )：广播消息到所有队列，没有任何处理，速度最快。

• 主题交换机( Topic exchange )：在直连交换机基础上增加模式匹配，也就是对 routing_key 进行模式匹配，

  * 代表一个单词，# 代表多个单词。

• 首部交换机( Headers exchange )：忽略 routing_key，使用 Headers 信息(一个 Hash 的数据结构)进行匹

  配，优势在于可以有更多更灵活的匹配规则。