Support for JCA Message Endpoints

Beginning with version 2.5, Spring also provides support for a JCA-based MessageListener container. The JmsMessageEndpointManager tries to automatically determine the ActivationSpec class name from the provider’s ResourceAdapter class name. Therefore, it is typically possible to provide Spring’s generic JmsActivationSpecConfig, as the following example shows:

<bean class="org.springframework.jms.listener.endpoint.JmsMessageEndpointManager">
	<property name="resourceAdapter" ref="resourceAdapter"/>
	<property name="activationSpecConfig">
		<bean class="org.springframework.jms.listener.endpoint.JmsActivationSpecConfig">
			<property name="destinationName" value="myQueue"/>
		</bean>
	</property>
	<property name="messageListener" ref="myMessageListener"/>
</bean>

Alternatively, you can set up a JmsMessageEndpointManager with a given ActivationSpec object. The ActivationSpec object may also come from a JNDI lookup (using <jee:jndi-lookup>). The following example shows how to do so:

<bean class="org.springframework.jms.listener.endpoint.JmsMessageEndpointManager">
	<property name="resourceAdapter" ref="resourceAdapter"/>
	<property name="activationSpec">
		<bean class="org.apache.activemq.ra.ActiveMQActivationSpec">
			<property name="destination" value="myQueue"/>
			<property name="destinationType" value="javax.jms.Queue"/>
		</bean>
	</property>
	<property name="messageListener" ref="myMessageListener"/>
</bean>

Using Spring’s ResourceAdapterFactoryBean, you can configure the target ResourceAdapter locally, as the following example shows:

<bean id="resourceAdapter" class="org.springframework.jca.support.ResourceAdapterFactoryBean">
	<property name="resourceAdapter">
		<bean class="org.apache.activemq.ra.ActiveMQResourceAdapter">
			<property name="serverUrl" value="tcp://localhost:61616"/>
		</bean>
	</property>
	<property name="workManager">
		<bean class="org.springframework.jca.work.SimpleTaskWorkManager"/>
	</property>
</bean>

The specified WorkManager can also point to an environment-specific thread pool — typically through a SimpleTaskWorkManager instance’s asyncTaskExecutor property. Consider defining a shared thread pool for all your ResourceAdapter instances if you happen to use multiple adapters.

In some environments (such as WebLogic 9 or above), you can instead obtain the entire ResourceAdapter object from JNDI (by using <jee:jndi-lookup>). The Spring-based message listeners can then interact with the server-hosted ResourceAdapter, which also use the server’s built-in WorkManager.

See the javadoc for JmsMessageEndpointManager, JmsActivationSpecConfig, and ResourceAdapterFactoryBean for more details.

Spring also provides a generic JCA message endpoint manager that is not tied to JMS: org.springframework.jca.endpoint.GenericMessageEndpointManager. This component allows for using any message listener type (such as a CCI MessageListener) and any provider-specific ActivationSpec object. See your JCA provider’s documentation to find out about the actual capabilities of your connector, and see the GenericMessageEndpointManager javadoc for the Spring-specific configuration details.

JCA-based message endpoint management is very analogous to EJB 2.1 Message-Driven Beans. It uses the same underlying resource provider contract. As with EJB 2.1 MDBs, you can use any message listener interface supported by your JCA provider in the Spring context as well. Spring nevertheless provides explicit “convenience” support for JMS, because JMS is the most common endpoint API used with the JCA endpoint management contract.