activemq-artemis/examples/jms/jms-context/readme.html

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<title>HornetQ JMS Context Example</title>
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<h1>JMS Context Example</h1>
<p>This example shows you how to send and receive a message to a JMS Queue using HornetQ by using a JMS Context</p>
<p>A JMSContext is part of JMS 2.0 and combines the JMS Connection and Session Objects into a simple Interface</p>
<h2>Example step-by-step</h2>
<p><i>To run the example, simply type <code>mvn verify</code> from this directory</i></p>
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<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 context</li>
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<code>jmsContext = cf.createContext();</code>
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<li>We create a JMS Producer, set the delivery mode and send a message all in one line. Note that we don't pass
a message to the send method but just a String.</li>
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<code>jmsContext.createProducer().setDeliveryMode(DeliveryMode.PERSISTENT).send(queue, "this is a string")</code>
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<li>We create a JMS message consumer and receive the payload of the message directly</li>
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<code>String payLoad = jmsContext.createConsumer(queue).receiveBody(String.class);</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>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 (jmsContext != null)
{
jmsContext.close();
}
}</code>
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