RabbitMQ - About ExchangeTypes 总结

总结一下几种ExchangeTypes。之前写发布/订阅模式时第一次提到了exchange type（见 http://www.linuxidc.com/Linux/2014-08/105107.htm）。即producer不是将消息直接放到队列中，而是先到exchange中，exchange主要用于控制消息到队列的路由,根据具体的exchange type将消息传给需要的队列或者直接废弃。在这一篇中总结一下那些用到的exchange type。一.Direct Exchangedirect exchange算是最基本的了。direct exchange用于将带上routing key的消息传值拥有相同routing key的队列中。当我们想用一个简单的标识符区别所有传入同一个exchange中的消息时direct exchange就非常合适。代码如下：
private static String DIRECT_EXCHANGE = "DIRECT_EXCHAGNE"; static class FanoutProducer { public static void main（String[] args） throws IOException { ConnectionFactory connectionFactory = new ConnectionFactory（）; Connection connection = connectionFactory.newConnection（）; Channel channel= connection.createChannel（）;; String content = "I miss the conversation"; channel.exchangeDeclare（DIRECT_EXCHANGE, ExchangeTypes.DIRECT）; channel.basicPublish（DIRECT_EXCHANGE, "alvez", null, content.getBytes（））; } } static class FanoutConsumer { public static void main（String[] args） throws IOException, InterruptedException { ConnectionFactory connectionFactory = new ConnectionFactory（）; Connection connection = connectionFactory.newConnection（）; Channel channel= connection.createChannel（）; String queueName = channel.queueDeclare（）.getQueue（）; channel.queueBind（queueName, DIRECT_EXCHANGE, "alvez"）; QueueingConsumer consumer = new QueueingConsumer（channel）; String s = channel.basicConsume（queueName, true, consumer）; System.out.println（s）; while （true） { QueueingConsumer.Delivery delivery = consumer.nextDelivery（）; String message = new String（delivery.getBody（））; String routingKey = delivery.getEnvelope（）.getRoutingKey（）; System.out.println（"From:" + routingKey + "":"" + message + """）; } }CentOS 5.6 安装RabbitMQ http://www.linuxidc.com/Linux/2013-02/79508.htmRabbitMQ客户端C++安装详细记录 http://www.linuxidc.com/Linux/2012-02/53521.htm用Python尝试RabbitMQ http://www.linuxidc.com/Linux/2011-12/50653.htmRabbitMQ集群环境生产实例部署 http://www.linuxidc.com/Linux/2012-10/72720.htmUbuntu下PHP + RabbitMQ使用 http://www.linuxidc.com/Linux/2010-07/27309.htm在CentOS上安装RabbitMQ流程 http://www.linuxidc.com/Linux/2011-12/49610.htm二.Fanout Exchangefanout和routing key无关，它将消息无差别地（indiscriminately）传送给所有队列。fanout exchange通常用于发布/订阅模式。将消息传送给不同的队列，不同的队列对同一种消息采取不同的行为。比如，现在有一个客户订单消息被三个队列接收，队列1完成该订单，队列2将订单写入日志，队列3将订单发给别的部门什么的。比如下面的代码，消费者可以获得routing key并输出，但能否获取与routing key无关：private static String FANOUT_EXCHANGE = "FANOUT_EXCHANGE"; static class DirectProducer {public static void main（String[] args） throws IOException {ConnectionFactory connectionFactory = new ConnectionFactory（）;Connection connection = connectionFactory.newConnection（）;Channel channel= connection.createChannel（）;; String content = "I miss the conversation";channel.exchangeDeclare（FANOUT_EXCHANGE, ExchangeTypes.FANOUT）;channel.basicPublish（FANOUT_EXCHANGE, "alvez", null, content.getBytes（））;}} static class DirectConsumer {public static void main（String[] args） throws IOException, InterruptedException {ConnectionFactory connectionFactory = new ConnectionFactory（）;Connection connection = connectionFactory.newConnection（）;Channel channel= connection.createChannel（）; String queueName = channel.queueDeclare（）.getQueue（）;channel.queueBind（queueName, FANOUT_EXCHANGE, ""）; QueueingConsumer consumer = new QueueingConsumer（channel）;String s = channel.basicConsume（queueName, true, consumer）;System.out.println（s）;while （true） {QueueingConsumer.Delivery delivery = consumer.nextDelivery（）;String message = new String（delivery.getBody（））;String routingKey = delivery.getEnvelope（）.getRoutingKey（）; System.out.println（"From:" + routingKey + "":"" + message + """）;} } }更多详情见请继续阅读下一页的精彩内容： http://www.linuxidc.com/Linux/2014-08/105107p2.htm