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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 Scheduled Message Example</h1>
<p>This example shows you how to send a scheduled message to a JMS Queue using HornetQ.</p>
<p>A Scheduled Message is a message that will be delivered at a time specified by the sender. To do this,
simply set a HDR_SCHEDULED_DELIVERY_TIME header property. The value of the property should be the time of
delivery in milliseconds. </p>
<p>In this example, a message is created with the scheduled delivery time set to 5 seconds after the current time.</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 queue object from JNDI</li>
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<code>Queue queue = (Queue) initialContext.lookup("/queue/exampleQueue");</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 producer = session.createProducer(queue);</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 scheduled message message which will be delivered in 5 sec.");</code>
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<li>We schedule the delivery time to be 5 sec later.</li>
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<code>
long time = System.currentTimeMillis();
time += 5000;
message.setLongProperty(MessageImpl.HDR_SCHEDULED_DELIVERY_TIME.toString(), time);
</code>
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<li>We send message to the queue</li>
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<code>messageProducer.send(message);</code>
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<li>We create a JMS Message Consumer to receive the message.</li>
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<code>MessageConsumer messageConsumer = session.createConsumer(queue);</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>We use a blocking receive() to consume the message and see when the message arrives.</li>
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<code>TextMessage messageReceived = (TextMessage) messageConsumer.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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</ol>
<h2>More information</h2>
<ul>
<li>User Manual's <a href="../../../docs/user-manual/en/html_single/index.html#scheduled-messages">Scheduled Messages chapter</a></li>
</ul>
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