embedding activemq in jboss

Today, I worked on a prototype web application that utilized JMS. We decided to use ActiveMQ for this. Here are the things I had to do to get it running embedded inside Jboss.

First, I followed the process described in the doc "Integrating ActiveMQ with Jboss".

By default ActiveMQ uses KahaDB for persistence, but I wanted to use our oracle db infrastructure for this. A bit of googling got me to Introduction to ActiveMQ persistence and that led to JDBC data source configuration . By now I got the ActiveMQ successfully embedded in Jboss and running.

Next, Instead of giving all the oracle db info in the broker-config.xml, I wanted to get it from Jboss managed jdbc datasource(which is being used by other applications also). So, I have already got mydatasource-ds.xml deployed inside deploy/ folder of jboss which looks like following

<datasources>
    <local-tx-datasource>
        <jndi-name>jdbc/mydatasource-ds</jndi-name>
 <connection-url>jdbc:oracle:thin:oracle_user/passwordu@host:1521/sid</connection-url>
        <driver-class>oracle.jdbc.driver.OracleDriver</driver-class>
        <min-pool-size>1</min-pool-size>
        <max-pool-size>20</max-pool-size>
        <metadata>
            <type-mapping>Oracle10g</type-mapping>
        </metadata>
    </local-tx-datasource>
</datasources>

In order to use above datasource, Here is what I had to put inside activemq-ra.rar/broker-config.xml file.

<beans ...>

  <!--  shutdown hook is disabled as RAR classloader may be gone at shutdown -->
  <broker xmlns="http://activemq.apache.org/schema/core" useJmx="true" useShutdownHook="false" brokerName="myactivemq.broker">
    ...
    ...
    <persistenceAdapter>
       <!-- kahaDB directory="activemq-data/kahadb"/ -->
       <!--kahaDB directory="${jboss.server.data.dir}/activemq"/ -->
       <jdbcPersistenceAdapter
           dataDirectory="${jboss.server.data.dir}/activemq"
           dataSource="#oracle-ds"/>
    </persistenceAdapter>

   ...
  </broker>

  <bean id="oracle-ds" class="org.springframework.jndi.JndiObjectFactoryBean">
    <property name="jndiName" value="java:jdbc/mydatasource-ds"></property>
  </bean> 
</beans>

Well, above did not work. What happened was that Jboss was trying to start ActiveMQ before deploying mydatasource-ds.xml which resulted in JNDI NameNotFoundException(as java:/jdbc/mydatasource-ds is not available until mydatasource-ds.xml gets deployed). So, in ActiveMQ configuration, I had to declare dependency on mydatasource-ds(so that it gets deployed first). To do it, I created a file named jboss-dependency.xml inside activemq-ra.rar/META-INF/ and pasted following on it.

<dependency xmlns="urn:jboss:dependency:1.0">
  <item whenRequired="Real">jboss.jca:service=DataSourceBinding,name=jdbc/mydatasource-ds</item>
</dependency>

Now, We are good :).

BTW, above is by no means an exhaustive list because as we go, we will make a lot of changes for the actual setup but above should get a new person started with less amount of trouble than I had.