spring-framework/framework-docs/modules/ROOT/pages/integration/jms/jca-message-endpoint-manager.adoc

[[jms-jca-message-endpoint-manager]]
= 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:

[source,xml,indent=0,subs="verbatim,quotes"]
----
	<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:

[source,xml,indent=0,subs="verbatim,quotes"]
----
	<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="jakarta.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:

[source,xml,indent=0,subs="verbatim,quotes"]
----
	<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, 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 {spring-framework-api}/jms/listener/endpoint/JmsMessageEndpointManager.html[`JmsMessageEndpointManager`],
{spring-framework-api}/jms/listener/endpoint/JmsActivationSpecConfig.html[`JmsActivationSpecConfig`],
and {spring-framework-api}/jca/support/ResourceAdapterFactoryBean.html[`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 JMS `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
{spring-framework-api}/jca/endpoint/GenericMessageEndpointManager.html[`GenericMessageEndpointManager`]
javadoc for the Spring-specific configuration details.

NOTE: 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.