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public class Example implements MessagingListener {
    MessagingClient messagingClient;
    public void start() throws MessagingException {
        Properties properties = new Properties();
        properties.setProperty(Context.INITIAL_CONTEXT_FACTORY,
                               "org.apache.activemq.jndi.ActiveMQInitialContextFactory");
        properties.setProperty(Context.PROVIDER_URL, "tcp://localhost:61616");
        properties.setProperty(JMSManager.CONNECTION_FACTORY_NAME, "ConnectionFactory");
        properties.setProperty("topic.fedora", "fedora.apim.*");
        messagingClient = new JmsMessagingClient("example1", this, properties, false);
        messagingClient.start();
    }
    public void stop() throws MessagingException {
        messagingClient.stop(false);
    }
    public void onMessage(String clientId, Message message) {
        String messageText = "";
        try {
            messageText = ((TextMessage)message).getText();
        } catch(JMSException e) {
            System.err.println("Error retrieving message text " + e.getMessage());
        }
        System.out.println("Message received: " + messageText + " from client " + clientId);
    }
}

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<?xml version="1.0" encoding="UTF-8"?>
<entry xmlns="http://www.w3.org/2005/Atom"
       xmlns:fedora-types="http://www.fedora.info/definitions/1/0/types/"
       xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <id>urn:uuid:3773e144-1b63-4dde-8786-464243af9186</id>
  <updated>2008-04-14T22:35:13.953Z</updated>
  <author>
    <name>fedoraAdmin</name>
    <uri>http://localhost:8080/fedora</uri>
  </author>
  <title type="text">purgeObject</title>
  <category term="demo:5" scheme="fedora-types:pid" label="xsd:string"></category>
  <category term="purge message" scheme="fedora-types:logMessage" label="xsd:string"></category>
  <category term="false" scheme="fedora-types:force" label="xsd:boolean"></category>
  <summary type="text">demo:5</summary>
  <content type="text">2008-04-14T22:35:13.953Z</content>
</entry>

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1. You will need to make a few jars available to Fedora so it can load and process the ActiveMQ configuration file. Drop the jars xbean-spring-3.4.3.jar and spring-context-2.5.6.jar files into the Fedora webapp WEB-INF/lib directory. Most spring It Fedora 3.8, updated copies of these jars are already included.  Most Spring applications provide these jars; if you are using Apache Servicemix as the container for your remote broker, they can be found in the SERVICEMIX_HOME/lib directory.

2. Create the Fedora activemq.xml file, put it in FEDORA_HOME/server/config.

   Code Block
   xml xml borderStyle solid
   <beans xmlns:amq="http://activemq.apache.org/schema/core"> <!-- ActiveMQ JMS Broker configuration --> <amq:broker id="broker" useShutdownHook="false"> <amq:managementContext> <amq:managementContext connectorPort="1093" createConnector="false"/> </amq:managementContext> <!-- Your remote broker, configured with failover --> <amq:networkConnectors> <amq:networkConnector uri="static:(failover:(tcp://0.0.0.0:61617))"/> </amq:networkConnectors> <!-- The directory where Fedora will store the ActiveMQ data --> <amq:persistenceAdapter> <amq:amqPersistenceAdapter directory="file:./data/amq"/> </amq:persistenceAdapter> </amq:broker> <!-- Set this to prevent objects from being serialized when passed along to your embedded broker; saves some overhead processing --> <bean id="jmsConnectionFactory" class="org.apache.activemq.ActiveMQConnectionFactory"> <property name="objectMessageSerializationDefered" value="false"/> </bean> </beans>

   This piece of the config file creates the bridge to the remote broker, configured in failover mode:

   Code Block
   xml xml borderStyle solid
   <amq:networkConnectors> <amq:networkConnector uri="static:(failover:(tcp://0.0.0.0:61617))"/> </amq:networkConnectors>

3. Configure Fedora to read the activemq.xml file upon startup, create the embedded broker.
   Make sure messaging is enabled in fedora.fcfg:

   Code Block
   xml xml borderStyle solid
   <module role="org.fcrepo.server.messaging.Messaging" class="org.fcrepo.server.messaging.MessagingModule"> <comment>Fedora's Java Messaging Service (JMS) Module</comment> <param name="enabled" value="true"/> [...]

   Also change the java.naming.provider.url parameter:

   Code Block
   xml xml borderStyle solid
   <param name="java.naming.provider.url" value="vm://localhost?brokerConfig=xbean:file:/path/to/fedora_home/server/config/activemq.xml"/>

4. Restart Fedora, and start up your remote broker (or the other way around: it no longer matters).
   The ActiveMQ failover transport documentation contains a list of useful parameters that you can use to configure connection management to the remote broker (max reconnect attempts, period between reconnects, etc.)

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