RabbitMQ学习(三)订阅/发布
1.RabbitMQ模型
前面所学都只用到了生产者、队列、消费者。如上图所示,其实生产者并不直接将信息传输到队列中,在生产者和队列中间有一个交换机(Exchange),我们之前没有使用到交换机是应为我们没有配置交换机,使用了默认的交换机。
有几个可供选择的交换机类型:直连交换机(direct), 主题交换机(topic), (头交换机)headers和 扇型交换机(fanout)
这里我们使用扇形交换机做一个简单的广播模型:一个生产者和多个消费者接受相同消息;
生产者代码:
public class Productor { public static void main(String[] //配置rabbitmq服务器地址 ConnectionFactory factory.setHost("localhost"); factory.setPort(5672); factory.setUsername("starktan"); factory.setPassword("starktan"); factory.setVirtualHost("/"); //建立连接和通道 Connection Channel channel = //声明一个扇形交换机 channel.exchangeDeclare("fanout", System.out.println("发送信息!"); String message = "WorkQueue channel.basicPublish("fanout", "", true, null, channel.close(); connection.close(); } } |
消费者代码:
public class Consumer { public static void main(String[] args) throws IOException, InterruptedException, TimeoutException { //创建连接和通道 ConnectionFactory factory = new ConnectionFactory(); factory.setHost("localhost"); final Connection connection = factory.newConnection(); ExecutorService service = Executors.newFixedThreadPool(10); for (int i = 0; i < 4; i++) { final int cur = i; service.submit(new Runnable() { Channel channel = connection.createChannel(); String queryname = channel.queueDeclare().getQueue(); public void run() { //创建队列消费者 QueueingConsumer consumer = new QueueingConsumer(channel); try { channel.queueBind(queryname,"fanout",""); channel.basicConsume(queryname,consumer); while (true) { QueueingConsumer.Delivery delivery = consumer.nextDelivery(); String message = new String(delivery.getBody()); System.out.println("线程 " + cur + " 获取到消息 " + message); } } catch (Exception e) { e.printStackTrace(); } } }); } service.shutdown(); } } |
运行效果: