About message driven bean

I use ori url to access my ejb runing on another jvm(sun app server).
like initialcontext.lookup("corbaname:iiop:192.0.0.1:3700#Bean");
in standalone app.
How do I call a message driven bean on sun app server in a standalone app which will be deployed in another pc.

Hi,
You cannot lookup MDB using JNDI. This is because MDB do not have a home interface and remote interface. Instead when a message producer sends a message to a queue or topic the application server invokes onMessage() method of MDB.
Please refer to following tutorial for further information.
http://java.sun.com/developer/technicalArticles/Ecommerce/jms/
HTH
VJ

Similar Messages

Question about message driven bean

hello
i can find tons of tutoriala about developing session bean and entity bean by using jdeveloper,but can't find even one article that tell me how to develop message driven bean and jms by using jdeveloper,who can help me,where can i find such tutorial?
thank you!

I setup breakpoints setting thru the MDB examples in j2eesdk 1.4.
I realize that the message to the being are being process sequentially.
Is there a way to process message in MDB concurrently?
Thank you.

A Question About Message Driven Bean Exception Handling

"Your onMessage method should handle all exceptions. It must not throw checked exceptions, and throwing a RuntimeException is considered a programming error."
The above sentence is from the JMS documentation.
I will use a message driven bean for guarenteeing to send an email with some critical info in case of an unexpected system failure. Say I was not able to save into db some critical info, therefore I want to send that info to myself with a mail to be able to handle that situation manually. Now in case of failure I will send a message to a queue which contains the critical info, and a message driven bean will listen for the message and send email to me. But what if the message driven bean fails ? If I am to handle any exceptions on my onMessage method, how will the messaging system be able to redeliver that message ? It seems to me the message will not remain in the queue anymore(I have consumed it) ?
Any help appreciated, thanks in advance.

Fatih.Karakoc wrote:
"Your onMessage method should handle all exceptions. It must not throw checked exceptions, and throwing a RuntimeException is considered a programming error."
The above sentence is from the JMS documentation.
I will use a message driven bean for guarenteeing to send an email with some critical info in case of an unexpected system failure. Say I was not able to save into db some critical info, therefore I want to send that info to myself with a mail to be able to handle that situation manually. Now in case of failure I will send a message to a queue which contains the critical info, and a message driven bean will listen for the message and send email to me. But what if the message driven bean fails ? If I am to handle any exceptions on my onMessage method, how will the messaging system be able to redeliver that message ? It seems to me the message will not remain in the queue anymore(I have consumed it) ?
You can configure your queue to guarantee delivery. If you use JTA you can also make it transational, so the message is put back on the queue in the event of failure. Your configuration should also include max retries and a failure queue to make sure you don't get stuck in an infinite loop where a message can never be processed.
Which app server are you using? WebLogic makes it pretty easy to set these config parameters.
%

Can you set isolation levels of message-driven bean transactions?

The problem: I have 3 different message-driven beans which each get a different type of message, except for a field that is common to all. That field is used as the primary key of an entity object. The message-driven beans configured to use a container managed transaction. Each message-driven bean, in processing the message, first does a lookup by primary key to see if the object associated with the key exists, and if it does not, it requests the entity's home object to create it. After that, they do further processing. The problem is that sometimes all the beans simultaneously get a message, resulting in each bean checking for the entity object at about the same time, and if they fail to find it (because none of them has created it yet), each creates an object, all with the same primary key. This is not caught until the beans start to complete their onMessage method, which I believe results in the container committing the transaction. One of the transactions will be committed successfully, while the other two will fail, get rolled back, and then be retried with the same message. The second time through, the other beans will find the entity object (since it has been created and committed) and they will complete correctly. In the end, they right thing occurs, except that there is a troubling exception or 2 in the log telling about the constraint violation (with the primary key) and the rollback. If it was just me, that would be fine, but our customer does not like to see exceptions in the log; that indicates to him that something is wrong.
So, I am looking for someway to make sure that the actions of the message-driven beans are serialized. One suggestion from a colleague was to set the isolation level of the transactions being used by the container in processing the message-driven beans' onMessage method. However, the documentation does not mention any way to do this for a message-driven bean. Suggestions?
Is the use of a UserTransaction a better way to do this? If I acquire a UserTransaction within the onMessage method of a message-driven bean, can I set its isolation level? How would this work? When I get a UserTransaction, does each client get a different transaction, or do they all get the same one?

(1) The WebLogic JMS "unit-of-order" feature is a heavily adopted feature that was specifically designed to handle similar use cases - see the JMS developer guide for extensive documentation. In your use case, if "key" is used to define UOO, then there's no limit on the number of keys that can be processed concurrently, but messages for any particular key will be processed single-threaded in the order in which they were first submitted.
Note that if you're using distributed destinations, the UOO feature is still fully supported - but the developer and/or administrator needs to decide whether to configure the destination to use "hash" or "path service" based routing (the JMS UOO edoc outlines the trade-offs).
(2) Another alternative is to use a single MDB with max-beans-free-pool that processes all three types (as the other poster suggested). I think this assumes all MDBs run on the same JVM.
(3) Another alternative is to use multiple queues, with a single MDB on each Q. Where some sort of hash algorithm is used to determine which Q is for the key. This approach is a "hand-coded" variant of the approach in (1) with "hash" based routing enabled...
(4) If all MDBs actually do run in the same JVM, a third alternative is to use code the application to use a common lock to protect each key, eg, something like:
// assume MyLock is simply a class with a "reference counter"
// assume some global "staticHM" hash map that is all MDBs can access
onMessage() {
MyLock lock = null;
key= msg.getKey();
synchronized(staticHM) {
lock = staticHM.get();
if (lock = null) {
lock = new lock();
staticHM.put(key, new lock());
lock.incRefCount();
try {
synchronized(lock) {
// only one onMessage will be able to lock a particular key at a time
do your work;
} finally {
synchronized(staticHT) {
if (lock.defRefCount() == 0) staticHM.remove(lock);
if (lock = null) staticHM.put(key);
If multiple threads get a message with the same key, then only one thread at a time will work on the key.
Hope this helps,
Tom

Create EJB 3.0 Message Driven Bean on a Oracle JMS (AQ)

Hi, I need to develop a EJB 3.0 Message Driven Bean. The MDB has to work on a Oracle AQ using Oracle JMS. Is there any how-to document giving an example about this issue. Can you give an example how to create the JMS destination in OC4J (how to configure the Oracle JMS AQ in OC4j), issue the JMS destination via annotions (resource injection) in the MDB. Please give me a working example of the MDB and a test client to produce a message. Regards, Arjan Jorritsma

Check your ejb-jar.xml and see if it has the version of "2.1" there...
If the application was depending upon EJB 3.0 annotations but it had a ejb-jar.xml that had version set to "2.1" and there was no oracle specific descriptor (orion-ejb-jar.xml) to designate it use the resource adapter; It would expect JMS destination and connection factory that is required for a JMS-MDB set in the ejb-jar.xml. So try to change the ejb-jar.xml to update the version to "3.0", OC4J would have parsed the annotation and combined the metadata with ejb-jar.xml and it would work.
-Frances

WLS10 - message-driven bean init-suspended / max-suspended params

I have a message-driven bean deployed with my app. I also have a custom start-up class that binds an Oracle AQ to Weblogic's JNDI tree that this message-driven bean connects to. If our DBAs perform database maintanance over the weekend and bring the db down for a period of time, WebLogic 'suspends' the message-driven bean when the db becomes unresponsive.
This is fine if once the db comes back up, WebLogic would resume the message-driven bean, but it doesn't. Via the admin console, I've tried re-initializing the bean, and I've tried resuming the bean...neither work...both result in a success status but the bean remains with a status of suspended.
Upon digging, I learned there are two parameters you can set for MDBs in the descriptor file or EJBGen annotations called initSuspendSeconds and maxSuspendSeconds...setting masSuspedSeconds to 0, according to the docs, say the bean will never suspend. I use the EJB annotation methodology and added these to my @MessageDriven annotation block. WebLogic Workshop will not generate these parameters in the resultant descriptor, nor will the build I perform to our development application server.
I then went to the admin console and manually updated these fields...help docs from the admin console say the default is 0...online docs and my installation on both windows and linux result in a default of 5 for initSuspendSeconds and 60 for maxSuspendSeconds. Ok...so I override these manually from the admin console once I've deployed my application...only thing it does is it requiresthe creation of a deployment plan now and asks for a directory in which to store this deployment plan. Fine...but honestly...what is the deal with these fields that they're being ignored by EJBGen, their defaults do not follow the docs and changing them via the admin console requires a deployment plan?
Anyone know anything about these params? I'm using WLS10MP1, btw, not 10.3. Not sure if that makes a difference...but just thought I'd include that tidbit.
Any help is greatly appreciated.
Thanks,
Edited by: rlb3778 on Feb 20, 2009 11:56 AM

So if you add the following annotations to the top of your MDB, EJBGen creates the suspended parameters in the descriptor?
@MessageDriven(ejbName = "MyBean",
          destinationJndiName = "SOME_QUEUE",
          destinationType = "javax.jms.Queue",
          transTimeoutSeconds = "3600",
          maxBeansInFreePool = "1",
          initialBeansInFreePool = "1",
          initSuspendSeconds = 0,
          maxSuspendSeconds = 0)
If I sent them to anything BUT 0 they're generated in the descriptor files but it ignores them if they're 0 and I WANT them to be 0 so the beans are never suspended. Oh well. I have a ticket open with support and they've confirmed that when they're et to 0 they're not generated and they claim because that's the default value which according to the spec, isn't...so I'm still waiting to hear back.
As for the JDBC connection, MDB resumeing upon reconnectiong of DB...our environments are very different...we do not have a JMS server running and maintained by Weblogic...we have a custom start-up class that binds our OracleAQ to Weblogic's JNDI tree and our MDB listens to the queue in the database. So i'm guessing because of that complex setup something is not working when the db queue disconnects. I will investigate our custom start-up class. Thanks for your help.

Message-driven bean problem (re-delivering of JMS msg)

Sorry for crossposting this (already posted in JMS forum), but perhaps someone here (who doesn't read JMS forum) knows the answer to this problem - it's basically a JMS problem, but closely related to EJB:
I browsed through all available docs but found no answer to this question: How can I force the re-delivery of a JMS message to happen in a few minutes instead of immediately?
I use JMS in an EJB container (SonicQ in Borland Enterprise Server 5.0.1) and messages are consumed by a message-driven bean. The problem arises when the bean sets the transaction in which the onMessage() function is called to rollback-only: Then, the message is redelivered immediately again causing an infinte processing loop and 100% CPU load on the machine until the message is finally consumed.
Is it possible to set a timeout for such a "temporarily rejected" message so that it is retries in a few minutes? Would that be a programming issue, or a configuration issue of the container and/or JMS?

Hi Chranq,
What you are talkin about is a container configuration thing as far as I can figure out. I may be that your JMS implementation doesn't support it.
/Stig

Message-Driven Bean using @Resource annotation

I am trying to run a Message-Driven Bean very simple example in https://glassfish.dev.java.net/javaee5/ejb/examples/MDB.html
I configured MDBQueueConnectionFactory and MDBQueue properly on glassfish admin console.
I cannot run the example using @Resource annotation. I don't understand why.
@Resource(mappedName="MDBQueueConnectionFactory")
private static QueueConnectionFactory queueCF;
@Resource(mappedName="MDBQueue")
private static Queue mdbQueue;But I can run this example modifying the source code using InitialContext instance and looking up for JMS Resources.
InitialContext ctx = new InitialContext();
QueueConnectionFactory queueCF=(QueueConnectionFactory)ctx.lookup("MDBQueueConnectionFactory");
QueueConnection queueCon = queueCF.createQueueConnection();
Queue mdbQueue=(Queue)ctx.lookup("MDB");
queueSender.send(mdbQueue, msg);
...I want to figure out why @Resource annotation do not work well. Any help?
Thanks in advanced any help.

Thanks for your reply.
The error that I get is a simple NullPointerException. Nothing else.
Like you said, I develop a servlet and I can use @Resource annotation without static reference, and it works.
public class TestMDB extends HttpServlet {
     private static final long serialVersionUID = 1L;
     @Resource(mappedName="MDBQueueConnectionFactory")
     private QueueConnectionFactory queueCF;
     @Resource(mappedName="MDB")
     private Queue mdbQueue;
     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
          PrintWriter out = response.getWriter();
          out.println("TEST MDB "+queueCF);
          QueueConnection queueCon;
          try {
               queueCon = queueCF.createQueueConnection();
               QueueSession queueSession = queueCon.createQueueSession
               (false, Session.AUTO_ACKNOWLEDGE);
               QueueSender queueSender = queueSession.createSender(null);
               TextMessage msg = queueSession.createTextMessage("hello");
               queueSender.send(mdbQueue, msg);
               out.println("Sent message to MDB");
               queueCon.close();
          } catch (JMSException e) {
               e.printStackTrace();
}But my question were about using @Resource annotation on a standalone client. I always get NullPointerException.
public class MDBClient {
    @Resource(mappedName="MDBQueueConnectionFactory")
    private static QueueConnectionFactory queueCF;
    @Resource(mappedName="MDB")
    private static Queue mdbQueue;
    public static void main(String args[]) {
     try {
            QueueConnection queueCon = queueCF.createQueueConnection();
            QueueSession queueSession = queueCon.createQueueSession
                (false, Session.AUTO_ACKNOWLEDGE);
            QueueSender queueSender = queueSession.createSender(null);
            TextMessage msg = queueSession.createTextMessage("hello");
            queueSender.send(mdbQueue, msg);
            System.out.println("Sent message to MDB");
            queueCon.close();
        } catch(Exception e) {
            e.printStackTrace();
}

Message Driven Bean debugging not supported in 9.0.3?

Message Driven Beans are now supported with the preview of 9.0.3, but you can't debug into them using the embedded container? Will this be resolved for the release version?

Brice --
Are you using the embedded help system or hosted documentation? I've just double-checked, and with the full jdev install, the "About Debugging PL/SQL Programs and Java Stored Procedures" is loading fine for me.
The PL/SQL variable should show up as well, without anything needing to be enabled on the server. What database version are you using, and what are the datatypes of the PL/SQL variables?
-- Brian
Hello,
We have downloaded JDev 903 Preview to try out the new PL/SQL debugging features, but it seems we are unable to inspect/watch/debug PL/SQL variables. The relevant panels are simply blank.
Strangely enough, the help files are also lacking on the subject (e.g. the "About debugging PL/SQL" help topic does not seem to exist).
Is there an option to turn on in the database server to view PL/SQL variables ?
Thanks
Regards
Brice

Best way to call web service from Message Driven Bean

I'm q'ing msgs up and would like to use a message driven bean to forward them to
an external web service. Weblogic workshop does not seem to support web service
controls in an EJB project. Any suggestions?
Thanks,
Paul

Paul,
A non-trivial alternative, since you have the WSDL, would be to forget about trying
to use generated client code and just use JAX-RPC dynamic invocation instead.
That's how I call external web services from within an EJB in situations in which
generated client code cannot be incorporated prior to deployment. Minimally all
that is required is the WSDL and the service name, port name, and operation name,
although if non-builtin parameter types are used then you will have to manipulate
the service's type mapping registry.
Mark
"Paul" <[email protected]> wrote:
>
I've taken our wsdl and generated a web service in Workshop 8.1 using
XMLBeans.
This produces a web page that contains a link"Java Proxy" for downloading
generated
client code. I assume this is the same as clientgen. It's interesting
that
it does not
use XMLBeans like the web service that generated it. It uses a different
serialization
method.
I've used this generated code to call the web service. Although the
client seems
to run
successfully to completion, I get the following error in the weblogic
server console:
<Sep 29, 2003 7:46:24 AM EDT> <Error> <WLW> <000000> <Failure=com.bea.wlw.runtim
e.core.request.ResponseValidationException: java.lang.RuntimeException:
Protocol
'http-soap' not available on this operation. [ServiceException]>
<Sep 29, 2003 7:46:24 AM EDT> <Warning> <WLW> <000000> <Returning HTTP
500 due
t
o SOAP fault occurring on DispFile=pjm.srcm.webservices.face.Receptor>
Frustrating...
Bruce Stephens <[email protected]> wrote:
Hi Paul,
Could you not first use clientgen on the external webservice, then take
the stubs it created, then add these to your code along with the
onMessage(Message msg) and roll it into the MBean?
We don't have exactly that example, but you might take a look at this
one to get some ideas:
http://webservice.bea.com/message.zip
Hope this helps,
Bruce
Paul wrote:
Bruce,
Don't think this will work for us. We are receiving data internallythrough
a JMS queue. We need to pull it off the queue (MDB), massage it alittle and
send it to an external web service. The link you sent me was howto implement
a web service with JMS.
I started out by trying to use the Web Service and JMS controls butit doesn't
seem like I can use a JMS control because that requires a conversationID,
which we don't have because nothing is comming in through a web services.
Paul
Bruce Stephens <[email protected]> wrote:
Hi Paul,
There is a chapter in the docs on this. See if this helps,
http://edocs.bea.com/wls/docs81/webserv/jms.html#1067060
Thanks,
Bruce
Paul wrote:
I'm q'ing msgs up and would like to use a message driven bean to
forward
them to
an external web service. Weblogic workshop does not seem to supportweb service
controls in an EJB project. Any suggestions?
Thanks,
Paul

Need to Parse XML Message from my Message Driven Bean

Hi
I am using Message Driven Beans for listening to a Queue .
I am getting a Big XML file from my Queue in form of a TextMessage .
Now my task is to read / parse the XML Message .
Please tell me what is the appropiate parsing technique i need to use (Should i use SAX or DOM )
Please share your ideas .
Thank you .

Generally you want to use SAX if the file is so big that loading it all in memory (as DOM does) will create memory problems.
Read about these methods on the wiki page for [JAXP.|http://en.wikipedia.org/wiki/Java_API_for_XML_Processing]

Message-driven beans Vs JMS

Hi,
what does the bean technology add to the JSM by using the message driven beans instead of just using the regular asynchronus JMS?

that's my question when and why should we chose:
1. simple asynchronous JMS
2. message-driven beansYou presumably mean:
1. "simple" JMS client
2. MDB JMS client
That'll depend first on your existing architecture.You'll go for the second option if you're already using EJB , as to leverage your existing IT investment.
Second, the EJB container gives you a number of services, so you don't have to worry about those yourself: life cycle management, scalability, transaction support, concurrency etc..
With a plain JMS client, you'll have to handle concurrency yourself, for example, by spawning different JMS instances.
If you're using an EJB container, that container will instantiate multiple MDB instances to handle multiple messages simultaneously.
OTOH, The EJB contract implies some limitations of use. For example, an MDB can be associated with only one queue or topic. So if you need a JMS client to be able to handle multiple queues ot topics, you'll need to create multiple MDB clients, or go for a simple non-MDB JMS consumer.

Measuring throughput of message driven bean

Hi,
I am trying to do some performance testing. I will be send millions of messages
to a JMS server. These will be consumed by message driven beans (some appropriate
number created at start up and kept in cache).
The message driven bean performs uses some local entity bean to perform some database
transaction.
I want to measure how many messages did each of the instance of bean process?
How much total time did each of message bean spend for their share of messages
and average time for consumption of a message in a bean (which is actually dividing
the total time for consumption of messages for a message bean dividing by total
number of messages (assuming that bean pick up message instantaneously).
Any idea if I could do that through weblogic console (I am using WL 6.1). Or by
using MBeans??
Any other idea will be useful.
Thanks
Mohit

Mohit,
Wily makes a tool tailored for doing the kind of performance evaluation you're
talking about. How useful it will be to your specific situation depends a lot
on some details that aren't in this post. Introscope (our tool) isn't designed
to crack apart individual instances of your message beans, but it is designed
to give you an idea of throughput per-component; exactly the kind of eval it looks
like you have in mind.
Roughly speaking... you can put rate and timer "tracers" on top of the relevant
methods in your bean's class. There are also increment and decrement tracers,
so you could match up send/receives between the components of your JMS app. This
will work across JVMs. There is (of course) some overhead for the monitoring,
but you could easily cancel out that number by doing a before and after and subtracting
our overhead-- you will be probably be impressed with how small it really it.
How many JVM instances are involved in your load test? How many different bean
classes? Are you using strictly the standard JMS API calls, or do you want to
monitor thing beyond that?
Drop me an e-mail if you're interested and we can talk about getting you set up
to try it out.
Dave Martin
[email protected]
Wily Technology, Inc.
(http://www.wilytech.com)
"Mohit Sehgal" <[email protected]> wrote:
>
Hi,
I am trying to do some performance testing. I will be send millions of
messages
to a JMS server. These will be consumed by message driven beans (some
appropriate
number created at start up and kept in cache).
The message driven bean performs uses some local entity bean to perform
some database
transaction.
I want to measure how many messages did each of the instance of bean
process?
How much total time did each of message bean spend for their share of
messages
and average time for consumption of a message in a bean (which is actually
dividing
the total time for consumption of messages for a message bean dividing
by total
number of messages (assuming that bean pick up message instantaneously).
Any idea if I could do that through weblogic console (I am using WL 6.1).
Or by
using MBeans??
Any other idea will be useful.
Thanks
Mohit

Is Message Driven Beans Supported in iAS 6.5?

Hello Everybody,
Admin guide of iAS 6.5 speaks about using Message driven beans (mdb). It also says that iAS 6.5 supports EJB 1.1 specification. But, EJB 1.1 specification doesnt support mdbs. Only EJB 2.0 does this. Then how come iAS 6.5 supports mdb, when it says that it is EJB 1.1 complaint and not EJB 2.0 complaint.
Please clear this doubt for me.
regards,
desigan

It is me who is posting again.
This is what provided in the Developer guide. I have just read it.
"iPlanet Application Server, Enterprise Edition 6.5, provides support for deploying message-driven beans. This implementation is based on the EJB 2.0 specifications,
and is for developer use only. The message-driven bean infrastructure in this release has not been tested in a production environment."
regards,
desigan

Send message from JSP page to Java message driven bean

Hi all
I'm using Jdev903.
I need to send a message from JSP page (Web Application) to Java Message Driven Bean.
* I created Message Driven Bean that named: MyMessageDrivenEJBBean
* I have configed jms.xml:
<topic-connection-factory name="ChatTopicConnectionFactory" location="jms/theTopicConnectionFactory"/>
<topic name="ChatTopic" location="jms/theTopic"/>
* In JSP page, my code is:
final Context ctx = new InitialContext();
// 1: Lookup ConnectionFactory via JNDI
TopicConnectionFactory factory =(TopicConnectionFactory)ctx.lookup("jms/theTopicConnectionFactory");
But trouble occurs is:
javax.naming.NameNotFoundException: jms/theTopicConnectionFactory not found
please help me!
thank a lot.

Welcome to the Sun forums.
1. Please post your code using code tags, this formats it so that it is easier for people to read and understand it. Click on 'CODE' above the text area when posting.
2. As far as possible, please post an SSCCE
What have learnt about JSPs and servlets till now? Because reading the values submitted in a form is pretty much the base of all operations. I suggest you Google for [servlet tutorials|http://www.google.com/search?q=servlet+tutorial] and [JSP tutorials|http://www.google.com/search?q=jsp+tutorial] and go through them thoroughly. After you understand what is to be done and what options are available to you, if you still face problems, please feel free to post your queries here. But this isn't exactly a site for tutorials, especially since there are so many good ones already out there, that explain all this stuff in detail. There's no point in re-inventing the wheel.
Hints: [ServletRequest#getParameter()|http://java.sun.com/javaee/5/docs/api/javax/servlet/ServletRequest.html#getParameter(java.lang.String)] and [RequestDispatcher#forward|http://java.sun.com/javaee/5/docs/api/javax/servlet/RequestDispatcher.html]

About message driven bean

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