RabbitMQ订阅

Question

我使用RabbitMQ来连接我的程序。 RMQ版本（3.3.5）。它与repo的java客户端一起使用。

// Connection part
@Inject
public AMQService(RabbitMQConfig mqConfig) throws IOException {
    this.mqConfig = mqConfig;
    connectionFactory.setHost(mqConfig.getRABBIT_HOST());
    connectionFactory.setUsername(mqConfig.getRABBIT_USERNAME());
    connectionFactory.setPassword(mqConfig.getRABBIT_PASSWORD());
    connectionFactory.setAutomaticRecoveryEnabled(true);
    connectionFactory.setPort(mqConfig.getRABBIT_PORT());
    connectionFactory.setVirtualHost(mqConfig.getRABBIT_VHOST());
    Connection connection = connectionFactory.newConnection();
    channel = connection.createChannel();
    channel.basicQos(1);
}

//Consume part
private static void consumeResultQueue() {
    final QueueingConsumer consumer = new QueueingConsumer(channel);
    Future resultQueue = EXECUTOR_SERVICE.submit((Callable<Object>) () -> {
        channel.basicConsume("resultQueue", true, consumer);
        while (true) {
            try {
                QueueingConsumer.Delivery delivery = consumer.nextDelivery();
                String message = new String(delivery.getBody(), "UTF-8");
                resultListener.onMessage(message);
            } catch (IOException | InterruptedException e) {
                e.printStackTrace();
            }
        }
    });
}

我想留下使用inifinty循环。当消息可以从队列中读取时，RMQ可以通知客户端吗？没有检查？

Answer 1

您可以创建一个扩展DefaultConsumer并覆盖handleDelivery。

的类

public class MyConsumer extends DefaultConsumer {

    public MyConsumer(Channel channel) {
        super(channel);
    }

    @Override
    public void handleDelivery(String consumerTag, Envelope envelope,
                           AMQP.BasicProperties properties, byte[] body) throws IOException {
        // do your computation
    }
}

使用channel.basicConsume(queueName, myConsumerInstance);

注册此消费者

请注意，通过这样做，handleDelivery将在rabbitmq客户端线程池中运行，因此您应该避免在此函数内进行任何长时间的计算。