in the hornetq, the consumer is automatically invoked? - hornetq

Question

I looked over all of examples in the hornetq, but I couldn't find the example that the consumer is automactically invoked whenever the message comess through the producer.
Please let me know about the example code or hint.
thanks in advance.

Answer 1

Use DefaultMessageListenerContainer. You can register a listener to it and consume messages asynchronously. Follow this link for more information about tuning MessageListenerContainer: http://bsnyderblog.blogspot.se/2010/05/tuning-jms-message-consumption-in.html.
Hornetq dependecies you need (I used a standalone hornetq-2.3.0.CR2) (You also need some spring jars):
<dependencies>
<!-- hornetq -->
<dependency>
<groupId>org.jboss.netty</groupId>
<artifactId>netty</artifactId>
<version>3.2.7.Final</version>
</dependency>
<dependency>
<groupId>org.hornetq</groupId>
<artifactId>hornetq-jms-client</artifactId>
<version>2.3.0.CR2</version>
</dependency>
<dependency>
<groupId>org.hornetq</groupId>
<artifactId>hornetq-core-client</artifactId>
<version>2.3.0.CR2</version>
</dependency>
<!-- hornetq -->
</dependencies>
The beans you should use in your applicationContext.xml (I didn't use jndi for getting ConnectionFactory and destinations; For this, you can follow this question):
<!-- It's ConnectionFactory to connect to hornetq. 5445 is hornetq acceptor port -->
<bean name="connectionFactory" class="messaging.jms.CustomHornetQJMSConnectionFactory">
<constructor-arg index="0" name="ha" value="false" />
<constructor-arg index="1" name="commaSepratedServerUrls" value="127.0.0.1:5445" />
</bean>
<bean id="destinationParent" class="messaging.jms.JmsDestinationFactoryBean" abstract="true">
<property name="pubSubDomain" value="false" /> <!-- default is queue -->
</bean>
<bean id="exampleDestination" parent="destinationParent">
<property name="destinationName" value="example" /> <!-- queue name -->
</bean>
<!-- MessageListener -->
<bean id="messageHandler" class="messaging.consumer.MessageHandler">
</bean>
<!-- MessageListenerContainer -->
<bean id="paymentListenerContainer" class="org.springframework.jms.listener.DefaultMessageListenerContainer">
<property name="destination" ref="exampleDestination" />
<property name="messageListener" ref="messageHandler" />
<property name="connectionFactory" ref="connectionFactory" />
<property name="sessionTransacted" value="true" />
<property name="concurrentConsumers" value="1" />
<property name="maxConcurrentConsumers" value="10" />
<property name="idleConsumerLimit" value="2" />
<property name="idleTaskExecutionLimit" value="5" />
<property name="receiveTimeout" value="3000" />
</bean>
CustomHornetQJMSConnectionFactory:
public class CustomHornetQJMSConnectionFactory extends org.hornetq.jms.client.HornetQJMSConnectionFactory
{
private static final long serialVersionUID = 1L;
public CustomHornetQJMSConnectionFactory(boolean ha, String commaSepratedServerUrls)
{
super(ha, converToTransportConfigurations(commaSepratedServerUrls));
}
public static TransportConfiguration[] converToTransportConfigurations(String commaSepratedServerUrls)
{
String [] serverUrls = commaSepratedServerUrls.split(",");
TransportConfiguration[] transportconfigurations = new TransportConfiguration[serverUrls.length];
for(int i = 0; i < serverUrls.length; i++)
{
String[] urlParts = serverUrls[i].split(":");
HashMap<String, Object> map = new HashMap<String,Object>();
map.put(TransportConstants.HOST_PROP_NAME, urlParts[0]);
map.put(TransportConstants.PORT_PROP_NAME, urlParts[1]);
transportconfigurations[i] = new TransportConfiguration(NettyConnectorFactory.class.getName(), map);
}
return transportconfigurations;
}
}
JmsDestinationFactoryBean (Used in destinationParent bean):
public class JmsDestinationFactoryBean implements FactoryBean<Destination>
{
private String destinationName;
private boolean pubSubDomain = false;
public void setDestinationName(String destinationName) {
this.destinationName = destinationName;
}
public void setPubSubDomain(boolean pubSubDomain) {
this.pubSubDomain = pubSubDomain;
}
#Override
public Class<?> getObjectType()
{
return Destination.class;
}
#Override
public boolean isSingleton()
{
return true;
}
#Override
public Destination getObject() throws Exception
{
if(pubSubDomain)
{
return HornetQJMSClient.createTopic(destinationName);
}
else
{
return HornetQJMSClient.createQueue(destinationName);
}
}
}
MessageHandler (Received messages go to onMessage method for process) (For simplicity, You can implement javax.jms.MessageListener instead of SessionAwareMessageListener):
public class MessageHandler implements org.springframework.jms.listener.SessionAwareMessageListener<Message>
{
#Override
public void onMessage(Message msg, Session session) throws JMSException
{
if(msg instanceof TextMessage)
{
System.out.println(((TextMessage)msg).getText());
session.commit();
}
else
{
session.rollback(); // send message back to the queue
}
}