<div class="wiki-content maincontent">


<h2><structured-macro ac:macro-id="266bfef6-a4d2-4ae3-9429-a53a5a694960" ac:name="excerpt" ac:schema-version="1"><parameter ac:name="atlassian-macro-output-type">INLINE</parameter><rich-text-body><p>Configuring an MDB to receive messages from ActiveMQ</p></rich-text-body></structured-macro></h2>
<p>There are three MDBs declared in the <link><attachment ri:filename="ejb-jar.xml"><page ri:content-title="JBoss Integration"></page></attachment><link-body>ejb-jar.xml</link-body></link> deployment descriptor.  For this example, I will be explaining how to configure the <code>TopicDurableMDB</code> to be invoked by JBoss when a message is received on an ActiveMQ Topic.</p>

<h3>The Bean</h3>
<p>In the <link><attachment ri:filename="ejb-jar.xml"><page ri:content-title="JBoss Integration"></page></attachment><link-body>ejb-jar.xml</link-body></link> deployment descriptor, the <code>TopicDurableMDB</code> is declared as follows:</p>
<structured-macro ac:macro-id="93b54ff4-22bf-4757-8139-2e2fd39d4021" ac:name="code" ac:schema-version="1"><parameter ac:name="">xml</parameter><parameter ac:name="title">ejb-jar.xml</parameter><plain-text-body> 
&lt;message-driven&gt;
   ...
   &lt;ejb-name&gt;TopicDurableMDB&lt;/ejb-name&gt;
   &lt;ejb-class&gt;com.panacya.platform.service.bus.mdb.SimpleMessageReceiverBean&lt;/ejb-class&gt;
   &lt;messaging-type&gt;javax.jms.MessageListener&lt;/messaging-type&gt;
   ...
   &lt;activation-config&gt;
      &lt;activation-config-property&gt;
         &lt;activation-config-property-name&gt;Destination&lt;/activation-config-property-name&gt;
         &lt;activation-config-property-value&gt;topic.testTopic&lt;/activation-config-property-value&gt;
      &lt;/activation-config-property&gt;
      &lt;activation-config-property&gt;
         &lt;activation-config-property-name&gt;DestinationType&lt;/activation-config-property-name&gt;
         &lt;activation-config-property-value&gt;javax.jms.Topic&lt;/activation-config-property-value&gt;
      &lt;/activation-config-property&gt;
      ...
   &lt;/activation-config&gt;
   ...
&lt;/message-driven&gt;
</plain-text-body></structured-macro>
<p>The <code>activation-config</code> element and it's child element, <code>activation-config-property</code>, are new elements for EJBs, so you might not be familiar with them.  I won't go into to much detail about them, but it is important to understand that this is the first mechanism you use to link an MDB to a JCA.  </p>

<h3>The Connector</h3>
<p>The two <code>activation-config-properties</code> shown above link to the following elements in the <a shape="rect" href="http://activemq.codehaus.org/checkout/activemq/modules/ra/src/rar/META-INF/ra.xml">ra.xml</a> file, which is contained within the <link ac:anchor="rarfile" ac:tooltip="The ActiveMQ JCA"><page ri:content-title="JBoss Integration"></page><link-body>activemq-ra-1.2.rar</link-body></link> file:</p>
<structured-macro ac:macro-id="7bf9366c-c37f-4f3a-8819-fc99e87c4104" ac:name="code" ac:schema-version="1"><parameter ac:name="">xml</parameter><parameter ac:name="title">ra.xml</parameter><plain-text-body>
&lt;inbound-resourceadapter&gt;
      ...
         &lt;activationspec&gt;
            &lt;activationspec-class&gt;org.activemq.ra.ActiveMQActivationSpec&lt;/activationspec-class&gt;
            &lt;required-config-property&gt;
               &lt;config-property-name&gt;Destination&lt;/config-property-name&gt;
            &lt;/required-config-property&gt;
            &lt;required-config-property&gt;
               &lt;config-property-name&gt;DestinationType&lt;/config-property-name&gt;
            &lt;/required-config-property&gt;
         &lt;/activationspec&gt;
      ...
&lt;/inbound-resourceadapter&gt;
</plain-text-body></structured-macro>
<p>In the <link><attachment ri:filename="ejb-jar.xml"><page ri:content-title="JBoss Integration"></page></attachment><link-body>ejb-jar.xml</link-body></link> file section shown above, the value of the <code>Destination</code> property is set to <code>topic.testTopic</code>.  This value is the physical name of the ActiveMQ destination the <code>TopicDurableMDB</code> will be receiving messages from and not a JNDI name.  In other words, the value of the <code>Destination</code> property has no meaning to JBoss.  It is purely an ActiveMQ setting. </p>

<h3>The Glue</h3>
<p>In JBoss, the thing which connects an inbound JMS destination to an MDB is a JBoss container.  To use ActiveMQ as the inbound message source for the <code>TopicDurableMDB</code> we must configure a new JBoss container.  We do this in the <link><attachment ri:filename="jboss.xml"><page ri:content-title="JBoss Integration"></page></attachment><link-body>jboss.xml</link-body></link> file.</p>

<p>Three things are needed in the <link><attachment ri:filename="jboss.xml"><page ri:content-title="JBoss Integration"></page></attachment><link-body>jboss.xml</link-body></link> file in order to tie an MDB to a connector.  They are:</p>

<ol><li>Configure a new <code>invoker-proxy-binding</code> that declares <code>JBossMessageEndpointFactory</code> as the <code>proxy-factory</code></li><li>Configure a new MDB container which uses the new <code>invoker-proxy-binding</code></li><li>Declare which MDBs should go into the new container</li></ol>


<p>This first snippet configures a new <code>invoker-proxy-binding</code>:</p>
<structured-macro ac:macro-id="b0c5918e-6353-42c5-8497-2dc26104f808" ac:name="code" ac:schema-version="1"><parameter ac:name="">xml</parameter><parameter ac:name="title">jboss.xml -- invoker-proxy-binding</parameter><plain-text-body>
&lt;invoker-proxy-binding&gt;
   &lt;name&gt;activemq-message-driven-bean&lt;/name&gt;
   &lt;invoker-mbean&gt;default&lt;/invoker-mbean&gt;
   &lt;proxy-factory&gt;org.jboss.ejb.plugins.inflow.JBossMessageEndpointFactory&lt;/proxy-factory&gt;
   ...
&lt;/invoker-proxy-binding&gt;
</plain-text-body></structured-macro>

<p>This second snippet configures a new MDB container which uses the <code>invoker-proxy-binding</code> configured above:</p>
<structured-macro ac:macro-id="f089de17-bdb2-4912-962b-802892187292" ac:name="code" ac:schema-version="1"><parameter ac:name="">xml</parameter><parameter ac:name="title">jboss.xml -- container-configuration</parameter><plain-text-body>
&lt;container-configuration&gt;
   &lt;container-name&gt;ActiveMQ Message Driven Bean&lt;/container-name&gt;
   &lt;call-logging&gt;false&lt;/call-logging&gt;
   &lt;invoker-proxy-binding-name&gt;activemq-message-driven-bean&lt;/invoker-proxy-binding-name&gt;
   ...
&lt;/container-configuration&gt;
</plain-text-body></structured-macro>

<p>This third snippet links the <code>TopicDurableMDB</code> to the <link ac:anchor="rarfile" ac:tooltip="The ActiveMQ JCA"><page ri:content-title="JBoss Integration"></page><link-body>activemq-ra-1.2.rar</link-body></link> connector and tells JBoss to put instances of <code>TopicDurableMDB</code> into the new MDB container declared above:</p>
<structured-macro ac:macro-id="88e4dbc4-c3e3-40aa-a1d9-ccf9cd47297e" ac:name="code" ac:schema-version="1"><parameter ac:name="">xml</parameter><parameter ac:name="title">jboss.xml -- TopicDurableMDB</parameter><plain-text-body>
&lt;message-driven&gt;
   &lt;ejb-name&gt;TopicDurableMDB&lt;/ejb-name&gt;
   &lt;resource-adapter-name&gt;activemq-ra-1.2-SNAPSHOT.rar&lt;/resource-adapter-name&gt;
   &lt;configuration-name&gt;ActiveMQ Message Driven Bean&lt;/configuration-name&gt;
&lt;/message-driven&gt;
</plain-text-body></structured-macro>

<p>The above examples highlight the key configuration settings needed to enable MDBs deployed in JBoss to process messages from an ActiveMQ destination.  </p>

<p>You can try the above example, plus a few more, by downloading the <link><attachment ri:filename="activemq-jboss-test.zip"><page ri:content-title="JBoss Integration"></page></attachment><link-body>activemq-jboss-test.zip</link-body></link> file which contains the complete sample project.</p></div>