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https://issues.apache.org/jira/browse/ACTIVEMQ6-3 We are renaming packages from activemq6 to activemq as that's more generic and version independent The previous commit renamed the directories. On this commit now I'm changing the code. If we changed the code and the directories on the same commit git would remove and add a lot of files without recognizing the renames.
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<h1>JMS Topic Example</h1>
<p>This example shows you how to send and receive a message to a JMS Topic with HornetQ.</p>
<p>Topics are a standard part of JMS, please consult the JMS 1.1 specification for full details.</p>
<p>A Topic is used to send messages using the publish-subscribe model, from a producer to 1 or more consumers.</p>
<h2>Example step-by-step</h2>
<p><i>To run the example, simply type <code>mvn verify</code> from this directory</i></p>
<ol>
<li>First we need to get an initial context so we can look-up the JMS connection factory and destination objects from JNDI. This initial context will get it's properties from the <code>client-jndi.properties</code> file in the directory <code>../common/config</code></li>
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<code>InitialContext initialContext = getContext();</code>
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<li>We look-up the JMS topic object from JNDI</li>
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<code>Topic topic = (Topic) initialContext.lookup("/topic/exampleTopic");</code>
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<li>We look-up the JMS connection factory object from JNDI</li>
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<code>ConnectionFactory cf = (ConnectionFactory) initialContext.lookup("/ConnectionFactory");</code>
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<li>We create a JMS connection</li>
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<code>connection = cf.createConnection();</code>
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<li>We create a JMS session. The session is created as non transacted and will auto acknowledge messages.</li>
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<code>Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);</code>
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<li>We create a JMS message producer on the session. This will be used to send the messages.</li>
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<code>MessageProducer messageProducer = session.createProducer(topic);</code>
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<li>We create a JMS Message Consumer, messageConsumer1, to receive the message.</li>
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<code>MessageConsumer messageConsumer = session.createConsumer(topic);</code>
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<li>We create a JMS Message Consumer, messageConsumer2, to also receive the message.</li>
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<code>MessageConsumer messageConsumer2 = session.createConsumer(topic);</code>
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<li>We create a JMS text message that we are going to send.</li>
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<code>TextMessage message = session.createTextMessage("This is a text message");</code>
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<li>We send message to the topic</li>
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<code>messageProducer.send(message);</code>
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<li>We start the connection. In order for delivery to occur on any consumers or subscribers on a connection, the connection must be started</li>
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<code>connection.start();</code>
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<li>The message arrives at the first consumer</li>
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<code>TextMessage messageReceived = (TextMessage) messageConsumer1.receive();</code>
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<li>The message arrives at the second consumer</li>
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<code>messageReceived = (TextMessage) messageConsumer2.receive();</code>
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<li>And finally, <b>always</b> remember to close your JMS connections and resources after use, in a <code>finally</code> block. Closing a JMS connection will automatically close all of its sessions, consumers, producer and browser objects</li>
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<code>finally
{
if (initialContext != null)
{
initialContext.close();
}
if (connection != null)
{
connection.close();
}
}</code>
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