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No, name is the default attribute. So "jms/myTopic" is same as name="jms/myTopic"Misha wrote:Isn't the third option also wrong because of the missing name attribute and not just the static property?
@Resource("jms/myTopic")
public static Topic myTopic;
I see, thanks.admin wrote: No, name is the default attribute. So "jms/myTopic" is same as name="jms/myTopic"
HTH,
Paul.
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@Resource (lookup = "jms/theGlobalTopic", type=Destination.class, name="jms/myTopic")
@Stateless
@LocalBean
public class SomeEJB {
@Resource SessionContext sct;
// other code
}
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Destination myDest = (Destination) sct.lookup ("jms/myTopic");
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@Resource(name="jms/myTopic")
private Destination myTopic;
Yes, you would indeed to a lookup, but, as you mentioned below, on the context. (i.e. sessionContext.lookup("jms/myTopic") ) and not in @Resource.fjwalraven wrote:If I have a "jms Topic specified it in my Session bean's environment under the name "jms/myTopic" then for sure I won't inject the resource, but I would do a lookup of the resource.
Well, that's not necessarily true. One might want to do it to as it does make the code a little cleanerfjwalraven wrote: and not inject it in a field again... although, I agree it worksCode: Select all
@Resource(name="jms/myTopic") private Destination myTopic;
Not sure if it is a trick question but one should know the difference between lookup and name. Ideally, lookup is used to lookup a resource that is available in the global jndi name space and make it available in the local name space under "name". If you already have a name in your local name space why would you use lookup?Or is this just a trick question to see whether people know the difference between "name" and "lookup"?
On the other hand if I know the name in the Global JNDI, why would I use it under another name in my Session Bean I would just inject it like this:If you already have a name in your local name space why would you use lookup?
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@Resource (lookup = "jms/theGlobalTopic")
Destination myDest
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@MessageDriven (name ="ListenerFacadeMDB", mappedName="jms/NewMessage",
activationConfig = {
@ActivationConfigProperty(propertyName="acknowledgeMode", propertyValue="Auto-acknowledge"),
@ActivationConfigProperty(propertyName="destinationType", propertyValue="javax.jms.Queue")})
public class ListenerFacadeEJB implements MessageListener{
private final static String PUBLISH_TOPIC_JNDI_NAME = "jms/PublishingTopic";
@Resource (mappedName = "jms/NewMessageFactory")
private ConnectionFactory mJMSConnectionFactory;
// attempt to inject a topic , but got an exception here
@Resource(name="myTopic")
private Topic mForwardingTopic;
@Override
public void onMessage(Message inReceivedMessage){
Connection theForwardingConnection = null;
try{
theForwardingConnection = mJMSConnectionFactory.createConnection();
Session theForwardingSession =
theForwardingConnection.createSession(false,Session.AUTO_ACKNOWLEDGE);
theForwardingMsgProducer = theForwardingSession.createProducer(mForwardingTopic);
.....
}
catch (final Exception e){
e.printStackTrace();
}
finally {
closeJmsResources(theForwardingConnection);
}
}
....
}
MDB00050: Message-driven bean [MDBFacade:ListenerFacadeMDB]: Exception in creating message-driven ejb : [com.sun.enterprise.container.common.spi.util.InjectionException: Exception attempting to inject Unresolved Message-Destination-Ref myTopic@java.lang.String@null into class com.ivan.listeners.ListenerFacadeEJB]
Severe: com.sun.enterprise.container.common.spi.util.InjectionException