JMS Redelivery Configuration

I recently had to help a client tune JMS redelivery on rollback. The application would post a message to a Queue with persistence, and a set of MDB's would pull these messages and tries to send them over to another point using Web Services, SMS, Email etc. However, if the sending fails, the requirement is to retry the operation by rolling back the read, so that the redelivery count could be used to discard messages on a threshold, or place them into a dead letter queue for manual action etc.

However, if a redelivery time is not specified, the messages keeps rollingback, and immidiately redelievred, which is of no use whatsoever! Though some JMS providers lets you easily configure this (e.g. WebLogic), I came across a JIRA for ActiveMQ, and a set of links that suggested incapability for JBoss.

It will also be impossible to write a MessageSelector, that is expected to pull only messages with say: (JMS_JBOSS_REDELIVERY_COUNT < 3) OR (JMSRedelivered IS FALSE)etc.

The correct trick, is to set the following properties, when placing the message on the Queue, and let the subscribers simply pull the messages out without any selectors etc..

message.setIntProperty("JMS_JBOSS_REDELIVERY_DELAY", 10000);
message.setIntProperty("JMS_JBOSS_REDELIVERY_LIMIT", 3);

The above correctly delays redeliveries to 10 seconds, with a maximum of 3 redeliveries, until the message is placed into the dead letter queue.

Logger for Axis2 now available too

I have just uploaded the Logger for Apache Axis2 to the utilities here. See the sample client found here on how to integrate this with a typical Axis2 client. Basically you will need to copy the deployable MAR file into your Axis2 repository/modules directory. Configuration of the module will be via your axis2.xml in the form shown below:

...

<module ref="logger"/>
<moduleConfig name="logger">
<parameter name="rootPath">/tmp/x/y</parameter>
<parameter name="identifier">cfg1</parameter>
<parameter name="enabled">true</parameter>
<parameter name="enableJMX">true</parameter>
</moduleConfig>

...

Connecting via JMX/JConsole allows you to enable/diable the Logger on demand, and can easily be modified to report statistics, response time of the backend service etc.. Let me know how you like this, and what would make this even more helpful