| <div class="docbook"><div class="navheader"><table summary="Navigation header" width="100%"><tr><th align="center" colspan="3">Appendix D. PooledConnectionFactory</th></tr><tr><td align="left" width="20%"><a accesskey="p" href="JMS-Client-0-8-Appendix-JMS-Extensions-Binding.html">Prev</a> </td><th align="center" width="60%"> </th><td align="right" width="20%"> <a accesskey="n" href="JMS-Client-0-8-Appendix-Tomcat-JNDI-Integration.html">Next</a></td></tr></table><hr /></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a id="JMS-Client-0-8-Appendix-PooledConnecytionFactory"></a>Appendix D. PooledConnectionFactory</h1></div></div></div><p>Qpid client provides <code class="literal">PooledConnectionFactory</code> which is a special |
| implementation of <a class="link" href="http://docs.oracle.com/javaee/6/api/javax/jms/ConnectionFactory.html" target="_top">ConnectionFactory</a> supporting <a class="link" href="http://docs.oracle.com/javaee/6/api/javax/jms/Connection.html" target="_top">Connection</a> pooling. </p><p> The <code class="literal">PooledConnectionFactory</code> caches a predefined number of connections |
| thus saving an application which connects frequently time. The <code class="literal">Connection</code> |
| instance is taken from the pool whenever method |
| <code class="literal">PooledConnectionFactory#createConnection()</code> is invoked and returned into the |
| pool when method <code class="literal">Connection#close()</code> is called.</p><p>A user can configure a maximum allowed number of connections to remain in pool (10 by |
| default) by calling <code class="literal">PooledConnectionFactory#setMaxPoolSize(int)</code>. When number |
| of connections exceeds the value set for maximum pool size, |
| <code class="literal">PooledConnectionFactory</code> starts to work as a normal <a class="link" href="http://docs.oracle.com/javaee/6/api/javax/jms/ConnectionFactory.html" target="_top">ConnectionFactory</a> and creates |
| a new connection every time method <code class="literal">PooledConnectionFactory#createConnection()</code> |
| is invoked.</p><p>The <a class="link" href="JMS-Client-0-8-Connection-URL.html" title="Chapter 7. Connection URLs">Connection URL</a> is set by invoking |
| method <code class="literal">PooledConnectionFactory#setConnectionURLString(String)</code>.</p><p>A user can specify the maximum time a connection may remain idle in pool by calling |
| <code class="literal">PooledConnectionFactory#setConnectionTimeout(long)</code> passing a value in |
| milliseconds. If connection is not used within the specified interval it is closed |
| automatically. </p><p>This implementation can be useful in <span class="emphasis"><em>Spring JMS</em></span> based applications. An |
| example below demonstrates how to configure <code class="literal">PooledConnectionFactory</code> in the |
| Spring xml configuration. </p><div class="example"><a id="d0e3470"></a><p class="title"><strong>Example D.1. Example of configuring <span class="emphasis"><em>PooledConnectionFactory</em></span> in spring xml |
| configuration.</strong></p><div class="example-contents"><pre class="programlisting"> |
| <bean id="pooledConnectionFactory" class="org.apache.qpid.client.PooledConnectionFactory"> |
| <!-- set maximum number of pool connections to 20--> |
| <property name="maxPoolSize" value="20"></property> |
| <!-- set the timeout for connection to remain open in pool without being used --> |
| <property name="connectionTimeout" value="60000"></property> |
| <!-- set connection URL as String --> |
| <property name="connectionURLString" value="amqp://guest:guest@clientid/default?brokerlist='tcp://localhost:5672?retries='300'&failover='nofailover''&maxprefetch='0'"></property> |
| </bean></pre></div></div><p><br class="example-break" /> |
| </p><p> |
| <span class="emphasis"><em>PooledConnectionFactory</em></span> spring bean can be configured with such |
| <span class="emphasis"><em>spring-jms</em></span> beans like |
| <span class="emphasis"><em>DefaultMessageListenerContainer</em></span> and <span class="emphasis"><em>JmsTemplate</em></span>. The |
| example below demonstrates how to do that </p><div class="example"><a id="d0e3493"></a><p class="title"><strong>Example D.2. Examples of configuring <span class="emphasis"><em>PooledConnectionFactory</em></span> with |
| <span class="emphasis"><em>DefaultMessageListenerContainer</em></span> and |
| <span class="emphasis"><em>JmsTemplate</em></span>.</strong></p><div class="example-contents"><pre class="programlisting"> |
| <bean id="jmsProducerTemplate" class="org.springframework.jms.core.JmsTemplate"> |
| <!-- set reference to pooledConnectionFactory bean --> |
| <property name="connectionFactory" ref="pooledConnectionFactory"></property> |
| <property name="defaultDestination" ref="destination" /> |
| </bean> |
| |
| <bean id="jmsContainer" class="org.springframework.jms.listener.DefaultMessageListenerContainer"> |
| <!-- set reference to pooledConnectionFactory bean --> |
| <property name="connectionFactory" ref="pooledConnectionFactory"/> |
| <property name="destination" ref="destination"/> |
| <property name="messageListener" ref="messageListener" /> |
| </bean></pre></div></div><p><br class="example-break" /> |
| </p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>If using <code class="literal">DefaultMessageListenerContainer</code> with |
| <code class="literal">cacheLevel</code> set to <code class="literal">NONE</code> it is important that |
| <code class="literal">maxConcurrentConsumer</code> does not exceed the value of maximum pool size set |
| on <code class="literal">PooledConnectionFactory</code> bean. If this is not the case, once the number |
| of in-use connections reaches the the <span class="emphasis"><em>PooledConnectionFactory#maxPoolSize</em></span> |
| a new connection will be opened for each and every message receipt i.e. a connection per |
| message anti-pattern.</p></div></div><div class="navfooter"><hr /><table summary="Navigation footer" width="100%"><tr><td align="left" width="40%"><a accesskey="p" href="JMS-Client-0-8-Appendix-JMS-Extensions-Binding.html">Prev</a> </td><td align="center" width="20%"> </td><td align="right" width="40%"> <a accesskey="n" href="JMS-Client-0-8-Appendix-Tomcat-JNDI-Integration.html">Next</a></td></tr><tr><td align="left" valign="top" width="40%">C.4. Binding Management </td><td align="center" width="20%"><a accesskey="h" href="JMS-Client-Book.html">Home</a></td><td align="right" valign="top" width="40%"> Appendix E. How to bind Qpid destinations and connection factories into Tomcat JNDI</td></tr></table></div></div> |
