|
|
|
Messaging Component |
The messaging component, of Arch4J,is a abstraction layer above JMS Messaging so that some of the more mundane Messaging code is all located in one place. The developer no longer needs to get the connection, manage the JNDI context, and close the objects. All that the developer needs to do is setup a properties file defining the QueueConnectionFactory JNDI name, use the ARCH4J Messaging API to get the various JMS Objects of interest.
|
| Get Started |
If you are installing as part of the full Arch4J distribution, you need to put the arch4j.jar file into your classpath.
If you are only interested in the messaging component, you need the base.jar, baseservices.jar, and arch4j_messaging.jar in your classpath.
You will also need to configure your JMS provider so it is accessible via JNDI..
|
| Overview |
The messaging model is designed around just being a thin veneer over the standard JMS api, which manages all the boring stuff. You will need to obtain a MessagingProvider, then a MessageQueueFacade, from this you can then create a QueueSender to send your messages and also create TextMessages etc... after sending your messages to finish up all you need to do is close the sender and the facade.
The reason for doing things this way is to move allot of the connection and queue management into a single class that can manage it all for you.
|
| How To |
In order to use the Messaging component, you will need to do four things:
- Configure the messaging properties in the messaging.properties file.
- Depending on the messaging factory you configured, there may well be a related properties file you need to configure, for example if you use webshpere you'll also need to configure messaging-websphere.properties.
- Configure the base services properties in baseservices.properties.
- Depending on the base services factory you configured, there may well be a related properties file you need to configure, for example if you use webshpere or weblogic you'll also need to configure system.properties.
- Get a reference to a MessageQueueFacade using the MessagingProvider class.
- Sending Messages.
- Finshing up.
| Property File Configuration |
|
The property file name is messaging.properties.
This is where you define the class names of the Factory implementations of MessageQueueFacade and MessageTopicFacade.
| Property Name |
Property Value |
Required |
| messagequeuefacade.class |
<class name of the implementation of the Message Queue Facade> |
Yes |
| messagetopicfacade.class |
<class name of the implementation of the Message Topic Facade> |
Yes |
Examples
Here is a sample property file for WebLogic messaging:
messagequeuefacade.class=org.arch4j.messaging.weblogic.WebLogicMessageQueueFacade
messagetopicfacade.class=org.arch4j.messaging.weblogic.WebLogicMessageTopicFacade
Here is a sample property file for Websphere messaging:
messagequeuefacade.class=org.arch4j.messaging.websphere.WebsphereMessageQueueFacade
messagetopicfacade.class=org.arch4j.messaging.websphere.WebsphereMessageTopicFacade
|
| Property File Configuration |
|
The property file name is messaging-websphere.properties.
This is where you define the JNDI names of the QueueConnectionFactory and TopicConnectionFactory.
| Property Name |
Property Value |
Required |
| queueConnectionFactoryLookup |
<JNDI name of the Queue Connection Factory> |
Yes |
| topicConnectionFactoryLookup |
<;JNDI name of the Topic Connection Factory> |
Yes |
Examples
Here is a sample property file:
queueConnectionFactoryLookup=jms/QCF2
topicConnectionFactoryLookup=jms/TCF
|
| Property File Configuration |
|
The property file name is baseservices.properties.
This is where you define the class name of the Factory implementations of BaseServices.
| Property Name |
Property Value |
Required |
| baseservices.class |
<class name of the implementation of the BaseServices> |
Yes |
Examples
Here is a sample property file:
baseservices.class=org.arch4j.baseservices.websphere.WebsphereBaseServices
|
| Property File Configuration |
|
The property file name is system.properties.
This is where you define the url of the JNDI service, plus additional data.
| Property Name |
Property Value |
Required |
| url |
<url of the JNDI service> |
Yes |
| initialContextFactory |
<class name of the Context Factory> |
No, only for Websphere |
Examples
Here is a sample property file for Weblogic:
url=t3://localhost:7001
Here is a sample property file for Websphere:
url=iiop://spidertest
initialContextFactory=com.ibm.websphere.naming.WsnInitialContextFactory
|
| Acessing the MessageQueueFacade |
|
To get a reference to the MessageQueueFacade, you need to use the MessagingProvider class. This class uses the
singleton pattern. To get the instance of the provider, use the getProvider() method.
You can then get get an instance of the MessageQueueFacade using getMessageQueueFacade( boolean isTransactional )
Examples
Getting an instance:
MessageQueueFacade qFacade = MessagingProvider.getProvider().getMessageQueueFacade(false);
|
|
|
| Sending Messages |
|
The process of sending a message is pretty simple. You just create a Sender, start it up, send your various messages and then close it.
Examples
Create a QueueSender and send a text message.
QueueSender sender = qFacade.createQueueSender("exampleQueue");
qFacade.startConnection();
TextMessage message = qFacade.createTextMessage(new StringBuffer("Hello Whirled"));
sender.send(message);
sender.close();
|
|
Finishing up
|
|
Once you've sent and reveiced your various messages, you just need to close the facade, which will do some cleanup behind the scenes.
Examples
Closing the facade:
qFacade.close();
|
|
|
