RabbitMQ交换机规则实例

　　RabbitMQ Exchange分发消息时根据类型的不同分发策略有区别，目前共四种类型：direct、fanout、topic、headers 。headers 匹配 AMQP 消息的 header 而不是路由键，此外 headers 交换器和 direct 交换器完全一致，但性能差很多，目前几乎用不到了。下面分别以实例的方式对这几种exchange进行讲解。

direct

　　首先我们以路由的方式对消息进行过滤，代码如下：

生产者

 public class RoutingSendDirect {

     private static final String EXCHANGE_NAME = "direct_test";

     private static final String[] routingKeys = new String[]{"info" ,"warning", "error"};

     public static void main(String[] args) throws IOException, TimeoutException {
         ConnectionFactory connectionFactory = new ConnectionFactory();
         connectionFactory.setHost("localhost");
         Connection connection = connectionFactory.newConnection();
         Channel channel = connection.createChannel();
         channel.exchangeDeclare(EXCHANGE_NAME,"direct");
         for(String key : routingKeys){
             String message = "RoutingSendDirect Send the message level:" + key;
             channel.basicPublish(EXCHANGE_NAME,key,null,message.getBytes());
             System.out.println("RoutingSendDirect Send"+key +"':'" + message);
         }
         channel.close();
         connection.close();
     }
 }

消费者

 public class ReceiveDirect1 {
     // 交换器名称
     private static final String EXCHANGE_NAME = "direct_test";
     // 路由关键字
     private static final String[] routingKeys = new String[]{"info" ,"warning"};

     public static void main(String[] args) throws IOException, TimeoutException {
         ConnectionFactory connectionFactory = new ConnectionFactory();
         connectionFactory.setHost("localhost");
         Connection connection = connectionFactory.newConnection();
         Channel channel = connection.createChannel();
         channel.exchangeDeclare(EXCHANGE_NAME,"direct");
         //获取匿名队列名称
         String queueName=channel.queueDeclare().getQueue();
         for(String key : routingKeys){
             channel.queueBind(queueName,EXCHANGE_NAME,key);
             System.out.println("ReceiveDirect1 exchange:"+EXCHANGE_NAME+"," +
                     " queue:"+queueName+", BindRoutingKey:" + key);
         }

         System.out.println("ReceiveDirect1  Waiting for messages");
         Consumer consumer = new DefaultConsumer(channel){
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
                 String msg = new String(body,"UTF-8");
                 System.out.println("ReceiveDirect1 Received '" + envelope.getRoutingKey() + "':'" + msg + "'");
             }
         };

         channel.basicConsume(queueName, true, consumer);
     }
 }

 public class ReceiveDirect2 {
     // 交换器名称
     private static final String EXCHANGE_NAME = "direct_test";
     // 路由关键字
     private static final String[] routingKeys = new String[]{"error"};

     public static void main(String[] args) throws IOException, TimeoutException {
         ConnectionFactory connectionFactory = new ConnectionFactory();
         connectionFactory.setHost("localhost");
         Connection connection = connectionFactory.newConnection();
         Channel channel = connection.createChannel();
         channel.exchangeDeclare(EXCHANGE_NAME,"direct");
         //获取匿名队列名称
         String queueName=channel.queueDeclare().getQueue();
         for(String key : routingKeys){
             channel.queueBind(queueName,EXCHANGE_NAME,key);
             System.out.println("ReceiveDirect2 exchange:"+EXCHANGE_NAME+"," +
                     " queue:"+queueName+", BindRoutingKey:" + key);
         }

         System.out.println("ReceiveDirect2  Waiting for messages");
         Consumer consumer = new DefaultConsumer(channel){
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
                 String msg = new String(body,"UTF-8");
                 System.out.println("ReceiveDirect2 Received '" + envelope.getRoutingKey() + "':'" + msg + "'");
             }
         };

         channel.basicConsume(queueName, true, consumer);
     }
 }

运行结果如下：

 RoutingSendDirect Sendinfo':'RoutingSendDirect Send the message level:info
 RoutingSendDirect Sendwarning':'RoutingSendDirect Send the message level:warning
 RoutingSendDirect Senderror':'RoutingSendDirect Send the message level:error

 ReceiveDirect1 exchange:direct_test, queue:amq.gen-HsUrzbjzto-K7HeigXSEfQ, BindRoutingKey:info
 ReceiveDirect1 exchange:direct_test, queue:amq.gen-HsUrzbjzto-K7HeigXSEfQ, BindRoutingKey:warning
 ReceiveDirect1  Waiting for messages
 ReceiveDirect1 Received 'info':'RoutingSendDirect Send the message level:info'
 ReceiveDirect1 Received 'warning':'RoutingSendDirect Send the message level:warning'

 ReceiveDirect2 exchange:direct_test, queue:amq.gen-i3NY12l3DqWjGapaBOCdwQ, BindRoutingKey:error
 ReceiveDirect2  Waiting for messages
 ReceiveDirect2 Received 'error':'RoutingSendDirect Send the message level:error'

fanout

　　fanout和别的ＭＱ的发布/订阅模式类似，实例如下：

生产者　　

 public class Pub {
     private static final String EXCHANGE_NAME = "logs";
     public static void main(String[] args) throws IOException, TimeoutException {
         ConnectionFactory factory=new ConnectionFactory();
         factory.setHost("localhost");
         Connection connection=factory.newConnection();
         Channel channel=connection.createChannel();
         //fanout表示分发，所有的消费者得到同样的队列信息
         channel.exchangeDeclare(EXCHANGE_NAME,"fanout");
         //分发信息
         for (int i=;i<;i++){
             String message="Hello World"+i;
             channel.basicPublish(EXCHANGE_NAME,"",null,message.getBytes());
             System.out.println("Pub Sent '" + message + "'");
         }
         channel.close();
         connection.close();
     }
 }

消费者

public class Sub {
    private static final String EXCHANGE_NAME = "logs";

    public static void main(String[] args) throws IOException, TimeoutException {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = factory.newConnection();
        Channel channel = connection.createChannel();

        channel.exchangeDeclare(EXCHANGE_NAME, "fanout");

        //产生一个随机的队列名称
        String queueName = channel.queueDeclare().getQueue();
        channel.queueBind(queueName, EXCHANGE_NAME, "");//对队列进行绑定

        System.out.println("Sub Waiting for messages");
        Consumer consumer = new DefaultConsumer(channel) {
            @Override
            public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
                String message = new String(body, "UTF-8");
                System.out.println("Sub Received '" + message + "'");
            }
        };
        channel.basicConsume(queueName, true, consumer);//队列会自动删除
    }
}

Topics

这种应该属于模糊匹配，* ：可以替代一个词，#：可以替代0或者更多的词，现在我们继续看看代码来理解

生产者　　

 public class TopicSend {
     private static final String EXCHANGE_NAME = "topic_logs";

     public static void main(String[] args) throws IOException, TimeoutException {
         Connection connection = null;
         Channel channel = null;
         try{
             ConnectionFactory factory=new ConnectionFactory();
             factory.setHost("localhost");
             connection=factory.newConnection();
             channel=connection.createChannel();

             //声明一个匹配模式的交换机
             channel.exchangeDeclare(EXCHANGE_NAME,"topic");
             //待发送的消息
             String[] routingKeys=new String[]{
                     "quick.orange.rabbit",
                     "lazy.orange.elephant",
                     "quick.orange.fox",
                     "lazy.brown.fox",
                     "quick.brown.fox",
                     "quick.orange.male.rabbit",
                     "lazy.orange.male.rabbit"
             };
             //发送消息
             for(String severity :routingKeys){
                 String message = "From "+severity+" routingKey' s message!";
                 channel.basicPublish(EXCHANGE_NAME, severity, null, message.getBytes());
                 System.out.println("TopicSend Sent '" + severity + "':'" + message + "'");
             }
         }catch (Exception e){
             e.printStackTrace();
             if (connection!=null){
                 channel.close();
                 connection.close();
             }
         }finally {
             if (connection!=null){
                 channel.close();
                 connection.close();
             }
         }
     }
 }

消费者　

 public class ReceiveLogsTopic1 {
     private static final String EXCHANGE_NAME = "topic_logs";

     public static void main(String[] args) throws IOException, TimeoutException {
         ConnectionFactory factory = new ConnectionFactory();
         factory.setHost("localhost");
         Connection connection = factory.newConnection();
         Channel channel = connection.createChannel();

         //声明一个匹配模式的交换机
         channel.exchangeDeclare(EXCHANGE_NAME, "topic");
         String queueName = channel.queueDeclare().getQueue();
         //路由关键字
         String[] routingKeys = new String[]{"*.orange.*"};
         //绑定路由
         for (String routingKey : routingKeys) {
             channel.queueBind(queueName, EXCHANGE_NAME, routingKey);
             System.out.println("ReceiveLogsTopic1 exchange:" + EXCHANGE_NAME + ", queue:" + queueName + ", BindRoutingKey:" + routingKey);
         }
         System.out.println("ReceiveLogsTopic1 Waiting for messages");

         Consumer consumer = new DefaultConsumer(channel) {
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
                 String message = new String(body, "UTF-8");
                 System.out.println("ReceiveLogsTopic1 Received '" + envelope.getRoutingKey() + "':'" + message + "'");
             }
         };
         channel.basicConsume(queueName, true, consumer);
     }
 }

  public class ReceiveLogsTopic2 {
     private static final String EXCHANGE_NAME = "topic_logs";

     public static void main(String[] argv) throws IOException, TimeoutException {
         ConnectionFactory factory = new ConnectionFactory();
         factory.setHost("localhost");
         Connection connection = factory.newConnection();
         Channel channel = connection.createChannel();
 //      声明一个匹配模式的交换器
         channel.exchangeDeclare(EXCHANGE_NAME, "topic");
         String queueName = channel.queueDeclare().getQueue();
         // 路由关键字
         String[] routingKeys = new String[]{"*.*.rabbit", "lazy.#"};
 //      绑定路由关键字
         for (String bindingKey : routingKeys) {
             channel.queueBind(queueName, EXCHANGE_NAME, bindingKey);
             System.out.println("ReceiveLogsTopic2 exchange:"+EXCHANGE_NAME+", queue:"+queueName+", BindRoutingKey:" + bindingKey);
         }

         System.out.println("ReceiveLogsTopic2 Waiting for messages");

         Consumer consumer = new DefaultConsumer(channel) {
             @Override
             public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws UnsupportedEncodingException  {
                 String message = new String(body, "UTF-8");
                 System.out.println("ReceiveLogsTopic2 Received '" + envelope.getRoutingKey() + "':'" + message + "'");
             }
         };
         channel.basicConsume(queueName, true, consumer);
     }
 }