批量使用JMS消息

Question

The MessageListener interface only defines a method onMessage that receives a single Message as argument. I'm looking for a way to get multiple Message s from a queue so that I can process the batch and then acknowledge all the Message s in the batch.

Is there such feature in JMS world? If no, is it supported by ActiveMQ as an extension?

Thanks, Mickael

Answer 1

This is explained in JMS 1.1 spec section 4.5.1 Synchronous Delivery :

A client can request the next message from a MessageConsumer using one of its receive methods. There are several variations of receive that allow a client to poll or wait for the next message.

There is even a code example in Section 9.2.2 Receiving a Message Synchronously :

TextMessage stockMessage;
stockMessage = (TextMessage)receiver.receive();

Note that you should also have a look into acknowledgement when using polling and batch processing - see section 4.4.11 Message Acknowledgment for further information on this. Especially interesting could be the following:

CLIENT_ACKNOWLEDGE - With this option, a client acknowledges a message by calling the message's acknowledge method. Acknowledging a consumed message automatically acknowledges the receipt of all messages that have been delivered by its session.

Answer 2

Yes this is part of the regular JMS API. Instead of doing your consumption in a MessageListener do it in a loop using MessageConsumer.receive() . For it to be transactionally batched, you need to use the SESSION_TRANSACTED acknowledgement mode, and call Session.commit() when you want to send the batch acknowledgement.

Take a look at the source code for the sjms-batch component in Apache Camel to see how this is done.