RabbitMQ学习（三）订阅/发布

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[] args) throws IOException, TimeoutException {
        //配置rabbitmq服务器地址
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        factory.setPort(5672);
        factory.setUsername("starktan");
        factory.setPassword("starktan");
        factory.setVirtualHost("/");
        //建立连接和通道
        Connection connection = factory.newConnection();
        Channel channel = connection.createChannel();
        //声明一个扇形交换机
        channel.exchangeDeclare("fanout", BuiltinExchangeType.FANOUT);
        System.out.println("发送信息！");
        String message = "WorkQueue Message number " + System.currentTimeMillis();
        channel.basicPublish("fanout", "", true, null, message.getBytes());
        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：