| # JMS Clustered Topic URI Example |
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| If you have not already done so, [prepare the broker distribution](../../../../README.md#getting-started) before running the example. |
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| To run the example, simply type **mvn verify** from this directory, or **mvn -PnoServer verify** if you want to start and create the broker manually. |
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| This example demonstrates a JMS Topic deployed on two different nodes. The two nodes are configured to form a cluster. |
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| We then create a subscriber on the topic on each node, and we create a producer on only one of the nodes. |
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| We then send some messages via the producer, and we verify that **both** subscribers receive all the sent messages. |
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| A JMS Topic is an example of **publish-subscribe** messaging where all subscribers receive all the messages sent to the topic (assuming they have no message selectors). |
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| This example uses JNDI to lookup the JMS Queue and ConnectionFactory objects. If you prefer not to use JNDI, these could be instantiated directly. |
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| Here's the relevant snippet from the broker configuration, which tells the broker to form a cluster between the two nodes and to load balance the messages between the nodes. |
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| This example differs from different-topic as it will use an URI to define the cluster connection. |
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| <cluster-connection-uri name="my-cluster" address="uri="multicast://my-discovery-group?messageLoadBalancingType=STRICT;retryInterval=500;connectorName=netty-connector;maxHops=1"/> |
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| For more information on ActiveMQ Artemis load balancing, and clustering in general, please see the clustering section of the user manual. |