.Net NMS.ActiveMQ should I store session and connection between message send calls

Question

I just started with the ActiveMQ thing and got several questions.

I should send messages using ActiveMQ

What I did for now :

public class ActiveMQSender
{
    private readonly Uri connectionUri;
    private readonly IConnectionFactory connectionFactory;

    private readonly string destinationName;

    public ActiveMQSender()
    {
        this.connectionUri = new Uri("activemq:tcp://localhost:61616");
        this.connectionFactory = new NMSConnectionFactory(this.connectionUri);
        this.destinationName = "queue://testQ";
    }

    public void Send(string msg)
    {
        using (var connection = this.connectionFactory.CreateConnection())
        using (var session = connection.CreateSession())
        {
            var destination = SessionUtil.GetDestination(session, this.destinationName);

            using (var producer = session.CreateProducer(destination))
            {
                connection.Start();
                var message = session.CreateTextMessage(msg);
                producer.Send(message);
            }
        }
    }
}

There will be only one instance of this class which will be injected as a constructor parameter.

I am affraid of overhead for connection, session and producer creation, because messages will be sent frequently (often than one message per 10 seconds) Should I reuse connection, session or producer instances, and how should I react to the connection failures? What is the common pattern in such scenarios?

score 2 · Accepted Answer · answered Dec 13 '12 at 23:48

NMS.ActiveMQ like the java client provides a failover transport which will automatically attempt to reconnect to the broker should the connection be lost. You can use that to minimize you failure handling code. Do some Google searching on the topic of failover transport in AMQ.

Recreating the connection and associated resources is not a lightweight operation so you're best bet is to cache them and reuse them for as long as you need that connection. In combination with failover you can reliably reuse the same MessageProducer over and over.

The model of NMS is much the same as JMS so doing some reading on JMS should provide enlightening.

score 1 · Answer 2 · answered Dec 13 '12 at 15:31

Presumably you're using NMS for this? As a suggestion you might want to consider using a blocking queue to throttle the messages and then send a chunk of n messages in a batch... Then you can keep your code and just publish the batch whilst disposing your connection and session and producer when you've finished as you are doing...

As for the connection failures - you should be able to hook up the exception listener to your session so that you get notified of any problems.

.Net NMS.ActiveMQ should I store session and connection between message send calls

2 Answers2