resin-messaging.xtp

RESIN 3.2 最新源码

  </ejb-message-bean>

</web-app>
</example>

</s2>

<s2 title="Cluster Client Topic">

<p>The client topic distributes messages to server topics in a
cluster.  Normally, only the sending methods are used for the client
topic; the receiving message beans are handled by the server topics.</p>

<p>The client topic needs to configure the cluster of the server topics.
The cluster can be different from the client's own cluster.</p>

<example title="resin-web.xml - client topic">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;jms-topic name="myTopic" uri="client:cluster=message-tier"/>

  &lt;jms-connection-factory uri="resin:"/>

&lt;/web-app>
</example>

</s2>
-->
</s1>

<s1 title="ConnectionFactory">

<p>The <code>ConnectionFactory</code> resource defines the JMS factory
for creating JMS connections.</p>

<example title="resin-web.xml - ConnectionFactory resource">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;jms-connection-factory name="jms/factory" uri="resin:"/>

&lt;/web-app>
</example>

<!-- XXX: ??
<p>
If an application creates a named queue or topic using the the JMS Session,
Resin's default behaviour is to create a memory queue or topic.  The 
<a href="#jdbc-manager">jdbc-manager</a> configuration of the connection factory 
causes creation of a jdbc queue or topic instead.
</p>

<example title="ConnectionFactory resource">
&lt;resource jndi-name="jms/factory"
           type="com.caucho.jms.ConnectionFactoryImpl"/&gt;
  &lt;init&gt;
    &lt;jdbc-manager&gt;
      &lt;data-source&gt;jdbc/database&lt;/data-source&gt;
    &lt;/jdbc-manager&gt;
  &lt;/init&gt;
&lt;/resource&gt;
</example>

<deftable-childtags>
<tr><td>client-id</td>
    <td>clientID value for durable subscriptions</td>
    <td>pseudo-random generated value</td>
    </tr>
<tr><td>jdbc-manager</td>
    <td>Use jdbc queues and topics for queues and topics created using the JMS Session object,
        see <a href="#jdbc-manager">jdbc-manager</a></td>
    <td>use a memory queue for created queues and topics</td>
    </tr>
</deftable-childtags>
-->
</s1>

<s1 title="BlockingQueue API">

<p>Resin's queues implement
the <code>java.util.concurrent.BlockingQueue</code> API.
Since the queues are registered with <a href="resin-ioc.xtp">Resin-IoC</a>
it's possible to use the <code>BlockingQueue</code> API directly
without the JMS API.</p>

<example title="TestServlet for JMS/BlockingQueue">
package example;

import java.util.concurrent.BlockingQueue;
import java.io.*;
import javax.servlet.*;
import javax.webbeans.*;

public class TestServlet extends GenericServlet {
  private @In BlockingQueue _queue;

  public void service(ServletRequest req, ServletResponse res)
    throws IOException, ServletException
  {
    PrintWriter out = res.getWriter();

    _queue.offer("test message");

    out.println("receive: " + _queue.poll());
  }
}
</example>

<p>The resin-web.xml configuration for the <code>BlockingQueue</code>
API is simple, only requiring the &lt;jms-queue> tag.  Because the
<code>BlockingQueue</code> uses Resin's JMS queue implementation directly,
it already knows where to get the <code>ConnectionFactory</code>.</p>

<example title="resin-web.xml configuration for memory BlockingQueue">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;jms-queue uri="memory:"/>

&lt;/web-app>
</example>

<s2 title="BlockingQueue for 3rd party JMS">

<p>The <code>BlockingQueue</code> API is also available for other JMS
providers.  You'll need to configure a <code>JmsBlockingQueue</code> in
the resin-web.xml to take advantage of it.</p>

<example title="Example: BlockingQueue WEB-INF/resin-web.xml">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;resource-adapter class="org.apache.activemq.ra.ActiveMQResourceAdapter">
      &lt;init server-url="vm://localhost"/>
  &lt;/resource-adapter>

   &lt;connection-factory uri="activemq:" name="factory"/>
 
   &lt;jms-queue uri="activemq:" name="queue">
       &lt;init physicalName="queue.test"/>
   &lt;/jms-queue>
 
  &lt;bean name="test" class="com.caucho.jms.queue.JmsBlockingQueue">
    &lt;init>
      &lt;factory>${factory}&lt;/factory>
      &lt;destination>${queue}&lt;/destination>
    &lt;/init>
  &lt;/bean>

&lt;/web-app>
</example>

</s2>

</s1>

<s1 title="Message Driven Beans">

<p>At some point, the application needs to receive messages from the
and process them.   Message driven beans provides a reliable, pooled
framework for receiving messages.  Applications just need to implement
a simple listener interface, and register to listen with a queue or topic.
</p>

<def title="javax.jms.MessageListener">
package javax.jms;

public interface MessageListener {

  public void onMessage(Message message);

}
</def>

<p>The implementation class can use any <a href="resin-ioc.xtp">Resin IoC</a>
capability, including injection, transaction annotations or interception.
For example, a simple listener might use <a href="amber.xtp">Amber/JPA</a> to
store messages in a database.</p>

<example title="demo/MyListener.java">
package demo;

import javax.jms.*;
import javax.persistence.*;
import javax.webbeans.*;

public class MyListener implements MessageListener
{
  private @In EntityManagerFactory _factory;

  public void onMessage(Message msg)
  {
    ObjectMessage oMsg = (ObjectMessage) msg;

    String value = oMsg.getObject();

    EntityManager em = _factory.createEntityManager();

    try {
      em.persist(new MyEntry(value));
    } finally {
      em.close();
    }
  }
}
</example>

<p>The configuration in the resin-web.xml file will connect the
<code>MyListener</code> class with the queue.  In this case, we'll
use the simple memory queue.</p>

<example title="WEB-INF/resin-web.xml">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;jms-connection-factory uri="resin:"/>
  &lt;jms-queue name="my_queue" uri="memory:"/>

  &lt;ejb-message-bean class="demo.MyListener">

    &lt;destination>${my_queue}&lt;/destination>

  &lt;/ejb-message-bean>

&lt;/web-app>
</example>

<p>The <code>&lt;ejb-message-bean></code> tag configures the message bean
pool with the application's listener specified by the <code>class</code>.
Resin will automatically create several <code>MyListener</code> instances
to process any queue messages.  The <code>&lt;destination></code> tag
specifies the queue to use.</p>

<p>Because the <code>&lt;ejb-message-bean></code> is a Resin IoC bean, it
can use an optional <code>&lt;init></code> block to configure any
parameters of <code>MyListener</code>.</p>

</s1>

<s1 title="JCA - Java Connector Architecture (.rar files)">

<p>The Java Connector Architecture is a driver architecture which
connects JMS providers like <a href="http://wiki.caucho.com/ActiveMQ">ActiveMQ</a>
with Resin's message driven beans and JMS sessions.  The JCA driver
will configure a <a href="http://wiki.caucho.com/Resource_Adapter">resource
adapter</a> and an <a href="http://wiki.caucho.com/Activation_Spec">activation
spec</a> to select a queue.</p>

<p>The resource adapter is the JCA driver's main service.  It handles
threading, socket connections, and creates any endpoints.</p>

<s2 title="JCA for message driven beans">

<p>The activation specification configures the JCA driver with a
message-driven bean.  The configuration looks like:</p>

<example title="WEB-INF/resin-web.xml ActiveMQ">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;resource-adapter class="org.apache.activemq.ra.ActiveMQResourceAdapter">
    &lt;init server-url="vm://localhost"/>
  &lt;/resource>

  &lt;ejb-message-bean class="qa.MyListener">

    &lt;activation-spec class="org.apache.activemq.ra.ActiveMQActivationSpec">
      &lt;init physical-name="queue.test"/>
    &lt;/activation-spec>

  &lt;/ejb-message-bean>

&lt;/web-app>
</example>

<p>Resin can also provide shortcuts for the driver classes using the
uri syntax:</p>

<example title="WEB-INF/resin-web.xml ActiveMQ">
&lt;web-app xmlns="http://caucho.com/ns/resin">

  &lt;resource-adapter uri="activemq:">
    &lt;init server-url="vm://localhost"/>
  &lt;/resource>

  &lt;ejb-message-bean class="qa.MyListener">

    &lt;activation-spec uri="activemq:">
      &lt;init physical-name="queue.test"/>
    &lt;/activation-spec>

  &lt;/ejb-message-bean>

&lt;/web-app>
</example>

</s2>

</s1>

<s1 title="Third-party JMS providers">

<ul>
<li><a href="http://wiki.caucho.com/ActiveMQ">ActiveMQ and Resin</a></li>
</ul>

</s1>

</body>
</document>