CORBA and EJB

Hi, I have problems when I make a Corba bind from an EJB session stateless : Corba object not found.
The object is found when I make a Corba bind from a java class and not from an EJB.
I use JDK 1.2, JBuilder 1.4 to develope EJB and Corba aplication and Weblogic 6.1 to deploy EJB.
If it isn't possible to make this, con you suggest another solution ?
Regards

Add this to ur code before initializing the ORB
System.setProperty("org.omg.CORBA.ORBClass", <ORBClass name here>) ; System.setProperty("org.omg.CORBA.ORBSingletonClass",<ORBSingletonClass name here>) ;
System.setProperty("ORBdomain_name", <ORBdomain_name here>)

Similar Messages

Poor perfomance CORBA and EJB in Oracle 8i

Here are the perfomance results of methods invocations
(1000 invocations of empty method in an loop)
Oracle 8i CORBA ~100ms per method
Oracle 8i EJB ~100ms per method
Jonas EJB server ~5ms per method
Java RMI ~3ms per method
Why Oracle 8i is so slow, even compared with noncommercial
EJB server Jonas? Is there any way to speed this up? Source codes of perfomance testing programs available upon request.

Oracle Jserver is quite fast and scalable. Nevertheless, there exists an important overhead in calling a CORBA or EJB method, so you should desing "heavy" functions in your EJB/CORBA objects. Instead of calling 10 times little methods, call one time a hevay one, and you'll find that JServer perforns very fast and reliably.
Best regards

EJB in WLS - CORBA and EJB on WLE

I have a client who is looking to attach a C++ client to their WLE
system, and, since
they now have WLS and WLE thanks to v. 5.1, they want to start moving
EJBs to the
WLS platform. The issue is this.
What if any are the issues regarding communicating between CORBA objects
on WLE
TO EJBs on WLS? I noticed that the illustrations always show the
communication coming
from the WLS side to the WLE side, but this client will be connected
directly to the WLE
platform, and wanting to access services on WLS.
Any issues, directions to documentation, or other advice regarding this
issue?
Thanks in advance,
Maffy
[maffy.vcf]

can anyone give code example for accessing WLS-EJB from WLE corba client.
louc wrote:
Interesting how things can be interpreted. What we need is direct input
from engineering on this.
In studying the only direct source of information we have... (the docs...
and ass-u-me'ing that the docs are correct) it appears that we can have a
CORBA object in WLE access a EJB in WLS through RMI/IIOP as long as the
parameter passing is kept to primitive data types. Any attempt to use the
'Object-by-Value' feature of CORBA 2.3 will result in a error because WLE
5.1 does not support passing 'Object-by-Value' at this time.
So to answer Maffy's question... yes a WLE CORBA client can access a WLS EJB
service through RMI over IIOP.
-- Lou Caraballo
Sr. Systems Engineer
BEA Systems Inc., Denver Telco Group
719-332-0818 (cell)
720-528-6073 (denver)
Robert Patrick <[email protected]> wrote in message
news:[email protected]...
The issue is that WLE does not yet support the RMI/IIOP standard (since itdoes not yet support
Objects by Value) not that the RMI/IIOP support in WLS 5.1 (as of SP3)does not support
bi-directional communication.
Papaya Head wrote:
so, you are saying bi-directional communication is not supported... can
you tell me what
rmi/iiop is for?
Thanks.
Maffy Finnerty wrote:
Okay, found a work around thanks to Deepak Sharma (THANK YOU,
DEEPAK!!) in the BEA
East office.
What my customer is going to have to do for now - until, as Will Lyonspointed out, the
bi-directional
communication is supported - is to build a Java "client" process onWLE that communicates
with the
RMI/EJB/Servlet process on WLS.
Deepak suggested that the best way, since they are a CORBA shop tryingto move to Java,
would be to have the C++ client talking to a CORBA/C++ object on WLEthat calls
a CORBA/Java object on WLE that acts as a client to WLS and accessesthe services of the
Java object on that server.
Another option would be to have the CORBA/C++ object on WLE use theJNI API to call a Java
object
on WLE that acts as a client to WLS and accesses the Java servicerunning there. There may
be better
performance from CORBA/C++ to CORBA/Java, though, so that was Deepak'sfirst choice.
Maffy
Papaya Head wrote:
you can also find an example in the WLS5.1 docs that includes a code
segment from C++
client of the RMI-IIOP hello example.
Will Lyons wrote:
The example application with C++ CORBA objects calling EJBs on a
Java Server refers
to C++ CORBA objects on the WLE T-Engine calling EJBs on the WLET-Engine. That
interoperability capability is supported, but it is not possibleto call the J-Engine
from the T-Engine in WLE 5.1. The primary usage model assumed inWLE 5.1 is calling
the WLE T-Engine from the J-Engine (or from WLS).
Will
Papaya Head wrote:
my understanding of your question is: you want some feature that
allows CORBA
objects to talk to EJB objects on WLS.
WLS5.1 has a new feature: RMI/IIOP, it's probably the featureyou want.
before WLS5.1, CORBA components couldn't talk to EJB componentsdirectly, but you
could make it happen by building a bridge from CORBA objects toEJB components on
WLS. that's probably what the references you read are talkingabout...
Maffy Finnerty wrote:
We haven't even gotten that far yet, re: transactions. Right
now the issue is
having an
in-house client (C++) connected to WLE but accessing services(EJBs) on WLS.
No talk
of transactions has occurred, yet.
However, I just found some conflicting information. I found areference to
building the
simpapp application to connect C++ objects on a CORBA serverto EJBs on a Java
Server,
which, if I'm reading it correctly, translates to WLE to WLS.However, I also
found a
reference to bidirectional interoperability that said that,for now, the
T-Engine could not
(WLE) could NOT invoke services on the J-Engine (WLS) but thatservices on the
T-Engine
(WLE) could BE invoked from requesters on the J-Engine (WLS).So, color me
confused.
maffy
Papaya Head wrote:
the first question that comes to my mind is:
can transaction run across components on WLE and components
on WLS? I don't
think it can...
Maffy Finnerty wrote:
I have a client who is looking to attach a C++ client to
their WLE
system, and, since
they now have WLS and WLE thanks to v. 5.1, they want tostart moving
EJBs to the
WLS platform. The issue is this.
What if any are the issues regarding communicating betweenCORBA objects
on WLE
TO EJBs on WLS? I noticed that the illustrations alwaysshow the
communication coming
from the WLS side to the WLE side, but this client will beconnected
directly to the WLE
platform, and wanting to access services on WLS.
Any issues, directions to documentation, or other adviceregarding this
issue?
Thanks in advance,
Maffy

Help newbie: in running sample CORBA and EJB

HI,
I am trying to run the samples that come along with the http
server for 8.1.7, all the examples work except for these two,
for the CORBA,I am able to load and publish, and works
perferctly from the client (used runit.bat) but when i try to
run from the web, it gives me a "class hell.Hello not found in
import",
and in EJB,
while i run makeit.bat it gives me an ora error which tells that
i am trying to insert a value too long for oracle, this comes
when trying to use loadjava.
can anybody help me out, any help is appreciated.
Thanks,
dharma

Hi,
If you are building & running EJB applications, please
use Oracle9iAS - OC4J, Oracle Containers for J2EE. It is a
robust, fast and a suggested environment for developing J2EE
based applications. Oracle database JVM should be used only for
deploying Java Stored Procedures. OC4J can be downloaded from OTN
, small footprint, easy to download and install and much easy to
configure. You will know it yourself once you download it.
Cheers
--Rajesh

JSP and EJB in 8i

Hi
This is not really a JDBC question but this board appears to be
the best fit.
I am interested in hearing your experience with using EJBs on
Oracle 8i. In particular, is it possible to use a JSP to access
EJBs?
Thanks
Pratul
null

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by DAVOR BORCIC ([email protected]):
Can anyone tell me where I can find Oracle JSP 1.1, mentioned in "Oracle 8i, Java Component Programming with EJB, CORBA and JSP" book?
The Oracle JSP release available on Technet is 1.0.
Oracle JSP 1.1 is, according to book, prerequisite for an installation on Tomcat.
Please advise.
<HR></BLOCKQUOTE>
Oracle iAS

Corba to Ejb

"I have a CORBA server implemented using VisiBroker 3.4. I am trying to access a simple HelloWorld stateless session bean deployed in WL 6.1 and getting the following exception:
[javax.naming.NameNotFoundException: org.omg.CosNaming.NamingContextPackage.NotFound]]
Here is the portion of the code that deals with the EJB:
String url = "iiop://localhost:7001";
String JNDI_NAME="stateless.HelloWorld";
HelloWorldHome hm = null;
HelloWorld ejb = null;
Properties p = new Properties();
p.put(Context.INITIAL_CONTEXT_FACTORY,
"com.sun.jndi.cosnaming.CNCtxFactory");
p.put(Context.PROVIDER_URL, url);
Context ctx= null;
try {
ctx=new InitialContext(p);
Debug.trace("Created an InitialContext Object");
Object home = ctx.lookup(JNDI_NAME);
Debug.trace("Got a home from look updir");
hm= (HelloWorldHome) PortableRemoteObject.narrow(home, HelloWorldHome.class);
Debug.trace("Narrow the home object");
ejb=hm.create();
Debug.trace("Created a home");
msg=ejb.getMessage("Corba request ejb response");
}catch(NamingException ne){
Debug.trace("The client was unable to lookup the EJ

Sal Roma <[email protected]> writes:
You need to provide more details of what you are trying to do. Are you
trying to use Visbroker Java? This is probably unworkable in Visi 3.4.
andy
"I have a CORBA server implemented using VisiBroker 3.4. I am trying to access a simple HelloWorld stateless session bean deployed in WL 6.1 and getting the following exception:
[javax.naming.NameNotFoundException: org.omg.CosNaming.NamingContextPackage.NotFound]]
Here is the portion of the code that deals with the EJB:
String url = "iiop://localhost:7001";
String JNDI_NAME="stateless.HelloWorld";
HelloWorldHome hm = null;
HelloWorld ejb = null;
Properties p = new Properties();
p.put(Context.INITIAL_CONTEXT_FACTORY,
"com.sun.jndi.cosnaming.CNCtxFactory");
p.put(Context.PROVIDER_URL, url);
Context ctx= null;
try {
ctx=new InitialContext(p);
Debug.trace("Created an InitialContext Object");
Object home = ctx.lookup(JNDI_NAME);
Debug.trace("Got a home from look updir");
hm= (HelloWorldHome) PortableRemoteObject.narrow(home, HelloWorldHome.class);
Debug.trace("Narrow the home object");
ejb=hm.create();
Debug.trace("Created a home");
msg=ejb.getMessage("Corba request ejb response");
}catch(NamingException ne){
Debug.trace("The client was unable to lookup the EJ--

Rmi and EJB

Hi guys,
i feel ejb is internally using rmi.Am i right?what are the differences between rmi and ejb and also what r the similarities?
Thanks
Regards
Vivek.S

RMI is just an API that allows Java classes to be invoked remotely. It uses Java Remote Method Protocol. But it also can use IIOP in which case this whole thing is called RMI-IIOP.
RMI doesnt provide any component model like EJB, that has several types of components with well defined behavior and purpose.
Since EJB's can be called remotely they may use JRMP but it's not mandatory.
EJB's have to use IIOP as a connection protocol to ensure interoperability among EJB servers and CORBA ORB's. So EJB' s use RMI as an API, but they have to support IIOP and optionally some other protocols like JRMP. For example, WebLogic supports some interesting protocol called T3.
best regards,
Maris Orbidans
SCJP SCWCD SCBCD

Diff b/w bc4j model and ejb model in adf11g

hi all,
iam murali iam new for adf 11g i have some dout's in adf11g ,can u please solve my probleam
what is the difference b/w bc4j componet and ejb componet,how to develop ejb application in adf11g.

,how to develop ejb application in adf11gTake a look at this tutorial for starters:
http://st-curriculum.oracle.com/obe/jdev/obe11jdev/ps1/ejb/ejb.html

JDBC, JMS and EJB transactions - possible problem?

Hello,
          I am using Oracle 9, Weblogic 8.1 SP 4, MyEclipse and
          XDoclet.
          In my current project I have the following piece of code
          in one of my message driven beans (code cited as pseudocode
          without unnecessary details):
          * @ejb.bean name="MyMessageProcessor"
          * display-name="Display name for a MyMessageProcessor"
          * jndi-name="ejb/MyMessageProcessor"
          * description="Bean MyMessageProcessor"
          * destination-type="javax.jms.Queue"
          * transaction-type="Container"
          * acknowledge-mode="Auto-acknowledge"
          * subscription-durability="Durable"
          * generate="false"
          * @ejb.transaction type="Required"
          public class MyMessageProcessor implements MessageDrivenBean, MessageListener {
          public void onMessage(Message msg) {
               try {
                    //obtaining connections to two different databases via JNDi
                    java.sql.Connection connOne =
                    ((DataSource)ctx.lookup("DataSourceOne")).getConnection();
                    java.sql.Connection connTwo =
                         ((DataSource)ctx.lookup("DataSourceTwo")).getConnection();
                    // performing some UPDATEs and INSERTs on connOne and connTwo
                    // calling some other methods of this bean
                    //creating the reply JMS message and sending it to another JMS queue
                    Message msgTwo = this.createReplyMessage(msg)
                    this.queueSender.send(msgTwo);
                    //commiting everything
                    this.queueSession.commit();
               } catch (Exception ex) {
               try {
                    if (this.queueSession!=null) this.queueSession.rollback();
               } catch (JMSException JMSEx) {};
               this.context.setRollbackOnly();
          Some days ago (before the final remarks from my client) there used to be only one DataSource configurated on the basis of the
          connection pool with non-XA jdbc driver. Everything worked fine
          including the transactions (if anything wrong happend not only wasn't the replymessage sent, but also no changes were written
          to database and the incomming message was thrown back to the my bean's
          queue).
          When I deployed the second DataSource I was informed by an error message, that only one non-transactional resource may
          participate in a global transaction. When I changed both datasources
          to depend on underlying datasources with transatcional (XA) jdbc drivers, everything stopped working. Even if
          EJB transaction was theoretically successfully rolledbacked, the changed were written to the database
          and the JMS message wasn't resent to the JMS queue.
          So here are my questions:
               1. How to configure connection pools to work in such situations? What JDBC drivers should I choose?
               Are there any global server configurations, which may influence this situation?
               2. Which jdbc drivers should I choose so that the container was able to rollback the database transactions
               (of course, if necessary)?
               3. Are there any JMS Queue settings, which would disable the container to send message back to the
               queue in case of setRollbackOnly()? How should be the Queue configurated?
          As I am new to the topic and the deadline for the project seems to be too close I would be grateful
          for any help.
          This message was sent to EJB list and JDBC list.
          Sincerely yours,
          Marcin Zakidalski

Hi,
          I found these information extremely useful and helpful.
          The seperate transaction for sending messages was, of course, unintentional. Thanks a lot.
          Anyway, I still have some problems. I have made some changes to the
          code cited in my previous mail. These changes included changing QueueSessions
          to non-transactional. I also set the "Honorate global transactions" to true.
          I am using XA JDBC driver. After setting "Enable local transactions" to false
          (I did it, because I assume that JDBC transactions should be part on the global
          EJB transaction) I got the following error:
          java.sql.SQLException: SQL operations are not allowed with no global transaction by default for XA drivers. If the XA
          driver supports performing SQL operations with no global transaction, explicitly allow it by setting
          "SupportsLocalTransaction" JDBC connection pool property to true. In this case, also remember to complete the local
          transaction before using the connection again for global transaction, else a XAER_OUTSIDE XAException may result. To
          complete a local transaction, you can either set auto commit to true or call Connection.commit() or Connection.rollback().
          I have also inspected the calls of methods of bean inside of onMessage() method just to check, whether
          the transactions are correctly initialized (using the weblogic.transaction.Transaction class).
          My questions are as follows:
          1. Any suggestions how to solve it? I have gone through the google answers on that problem and only
          thing I managed to realize that JDBC must start its own transaction. Is there any way to prohibit it
          from doing that? Can using setAutocommit(true/false) change the situation for better?
          2. How to encourage the JDBC driver to be a part of EJB transaction?
          3. As I have noticed each of ejb method has its own transactions (transactions have different
          Xid). Each method of the bean has "required" transaction attribute. Shouldn't it work in such
          way that if already started transaction exists it is used by the called method?
          4. The DataSources are obtained in my application via JNDI and in the destination environment I will have slight
          impact on the configuration of WebLogic. What is least problematic and most common WebLogic configuration which would
          enable JDBC driver to participate in the EJB transaction? Is it the WebLogic configuration problem or can it be
          solved programmically?
          Currently my module works quite fine when "enable local transactions" for DataSources is set to true, but this way
          I am loosing the ability to perform all actions in one transaction.
          Any suggestions / hints are more than welcomed. This message was posted to jdbc list and ejb list.
          Marcin

OC4J 9.0.3 and EJB 1.1 deployments???

I can not deploy my ejb1.1 beans on 9.0.3 container.
OC4J crashes with an XML parse error as a null pointer exception.
If I remove my O-R mappings from my orion-ejb-jar.xml file, the container starts up ok (app wont run as it needs the mappings)
9.0.3 docs claim I should be able to use my 1.1 ejb in this ejb 2.0 container.
Solaris release notes for 9.0.3 claim I must migrate to ejb2.0
Someone else posted this same question but got no replies.
Anyone else deployed ejb1.1 with OR mappings in 9.0.3 successfully yet?
thanks

I have tried migrating to an ejb2.0 set of beans and ejb-jar.xml file.
With no <query> tags installed for my finders I notice that a typical finder produces this:

This is vastly different from the 1.1 orion-ejb-jar.xml which would list ALL column names in the finder - hence how am I going to do a findAll? The currently generated sql is way off. Deployment of the "ormap" demo also shows a lack of column names in the generated SQL finder methods in orion-ejb-jar.xml.
Further, as soon as I introduce the query in the 2.0 version of ejb-jar.xml, the container dies with a null pointer exception. Removing this from the ejb-jar and bean deploys. Useless, cause theres no finders though.
Also, attempts to add to the <finder-method query=...> tag yield container crashes with null pointers too.
This is not very robust to say the least. Can you provide names of jar files that would cause such exceptions?
When NO query tag is inserted in the ejb-jar file, attempts to run a sample client using findByPrimaryKey return successfully but use of findAll causes timeouts similar to whats described in
"finders giving "timeout expired waiting for an instance" after 0, 1, or 2 calls" in this same forum.
Heres the query out of the ejb-jar.xml file...
<query>
<query-method>
<method-name>findAll</method-name>
<method-params></method-params>
</query-method>
<ejb-ql>
SELECT OBJECT(o) from IspTb o
</ejb-ql>
</query>
IspTb is the <abstract-schema-name> Tables exist in db.
The full error...which prevents deployment of the ejbs and hence no rewrite of the orion-ejb-jar file.
=========
10/23/02 1:54 PM: javax.ejb.EJBException: nested exception is: java.lang.NullPointerException
10/23/02 1:54 PM: java.lang.NullPointerException
10/23/02 1:54 PM: at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:274)
10/23/02 1:54 PM: at java.lang.ClassLoader.loadClass(ClassLoader.java:287)
10/23/02 1:54 PM: at com.evermind.naming.ContextClassLoader.loadClass(ContextClassLoader.java:135)
10/23/02 1:54 PM: at java.lang.ClassLoader.loadClass(ClassLoader.java:287)
10/23/02 1:54 PM: at com.evermind.naming.ContextClassLoader.loadClass(ContextClassLoader.java:135)
10/23/02 1:54 PM: at java.lang.ClassLoader.loadClass(ClassLoader.java:250)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getClass(PersistenceDescriptor.java:767)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getStateClass(PersistenceDescriptor.java:753)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getCMPFieldType(PersistenceDescriptor.java:1302)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.initializeFieldInfo(PersistenceDescriptor.java:1052)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getPersistentFieldInfo(PersistenceDescriptor.java:805)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.<init>(SQLGenerator.java:151)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:360)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:309)
10/23/02 1:54 PM: at com.evermind.server.ejb.deployment.EJBPackage.translateEjbqlQeries(EJBPackage.java:2100)
10/23/02 1:54 PM: at com.evermind.server.ejb.compilation.Compilation.translateEjbqlQeries(Compilation.java:140)
10/23/02 1:54 PM: at com.evermind.server.ejb.compilation.Compilation.compile(Compilation.java:178)
10/23/02 1:54 PM: at com.evermind.server.ejb.EJBContainer.postInit(EJBContainer.java:551)
10/23/02 1:54 PM: at com.evermind.server.Application.postInit(Application.java:431)
10/23/02 1:54 PM: at com.evermind.server.Application.setConfig(Application.java:136)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.addApplication(ApplicationServer.java:1635)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.initializeApplications(ApplicationServer.java:1585)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.setConfig(ApplicationServer.java:1240)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServerLauncher.run(ApplicationServerLauncher.java:93)
10/23/02 1:54 PM: at java.lang.Thread.run(Thread.java:479)
10/23/02 1:54 PM: javax.ejb.EJBException: nested exception is: java.lang.NullPointerException
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getClass(PersistenceDescriptor.java:770)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getStateClass(PersistenceDescriptor.java:753)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getCMPFieldType(PersistenceDescriptor.java:1302)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.initializeFieldInfo(PersistenceDescriptor.java:1052)
10/23/02 1:54 PM: at com.sun.enterprise.deployment.PersistenceDescriptor.getPersistentFieldInfo(PersistenceDescriptor.java:805)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.<init>(SQLGenerator.java:151)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:360)
10/23/02 1:54 PM: at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:309)
10/23/02 1:54 PM: at com.evermind.server.ejb.deployment.EJBPackage.translateEjbqlQeries(EJBPackage.java:2100)
10/23/02 1:54 PM: at com.evermind.server.ejb.compilation.Compilation.translateEjbqlQeries(Compilation.java:140)
10/23/02 1:54 PM: at com.evermind.server.ejb.compilation.Compilation.compile(Compilation.java:178)
10/23/02 1:54 PM: at com.evermind.server.ejb.EJBContainer.postInit(EJBContainer.java:551)
10/23/02 1:54 PM: at com.evermind.server.Application.postInit(Application.java:431)
10/23/02 1:54 PM: at com.evermind.server.Application.setConfig(Application.java:136)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.addApplication(ApplicationServer.java:1635)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.initializeApplications(ApplicationServer.java:1585)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServer.setConfig(ApplicationServer.java:1240)
10/23/02 1:54 PM: at com.evermind.server.ApplicationServerLauncher.run(ApplicationServerLauncher.java:93)
10/23/02 1:54 PM: at java.lang.Thread.run(Thread.java:479)

ABAP Objects and EJB

Hi every one,
Can <b>ABAP Objects and EJB</b> be compared?
-Naveen.

Hi Naveen,
Check this guide- might be useful-
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/dc09af90-0201-0010-d09b-bd611a11070b
Regards,
Moorthy

Using SWING and EJB

Had nebody used Swing for GUI and EJBs for business logic. HEre i need to use Swing for gui rather than JSPs.
Can nebody help??

My question is ...
How do u call EJBs from swing based applets..
In J2EE transaction management cud be done at server side but how will we manage with the swing app??

OC4J EJBQL and EJB 2.0 features

Hello Debu Panda and All
I've got all howtos and I mangaged to get some parts of OC4J [Oracle9iAS (9.0.3.0.0) Containers for J2EE (build 020323.1689)] working.
There are still some issues that are stalling our development. Could you please comment on them, maybe providing an estimate of when they will be solved/implemented?
First of all, a little background. Our application uses many Java Swing application clients that connect to the EAR application in the container.
The ear application has the following structure:
All database access (Oracle 8i, located in its own server) is done exclusively by means of CMP entity beans. A entity bean may access other entity beans. There are workflow session beans (stateful and stateless) that access the entity beans. All clients see only the workflow session beans (session beans fagade).
Our applicatoin is complex, having more than 80 session beans and more than 25 entity beans (not counting entity beans that exist only to represent relationships among entity beans).
There goes the questions:
1) It seems that entity beans cannot currently be referenced by remote interfaces. We couldn't deploy our application using it. Since we could use only local interfaces fot entity beans, thats what is been done now.
2) There is no CMR supported. Is this true?
3) EJBQL seems to be very limited. In the howto examples there are EJBQL statements that compare two numbers. However, when we tried to use String comparisons, it didn't work. Here is the statement:
"SELECT DISTINCT OBJECT(p) FROM Person p WHERE p.name = ?1"
If I compile, package and deploy the ear applicatin with the above EJBQL statement, OC4J generates an exception when executing the finder method. The exception is:
"java.rmi.NoSuchObjectException: Session has timed out
at com.evermind.server.ejb.StatefulSessionEJBObject.throwPassivisat
ception(StatefulSessionEJBObject.java:188)
at Cad023Remote_StatefulSessionBeanWrapper0.obterPessoasPorParteNom
023Remote_StatefulSessionBeanWrapper0.java:754)
at java.lang.reflect.Method.invoke(Native Method)
at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:8
at com.evermind.util.ThreadPoolThread.run(ThreadPoolThread.java:64)"
If I remove the where clause, the expection is gone. However, I get all records. ;-)
4) It seems that all EJBQL clauses must be capitalized. Is this true?
FINALY)
Is there a newer OC4J build that could use to get the development going? Do you know where there will be one? Is there any way of contacting the OC4J development team to report bugs?
If you would like, we could discuss it in private e-mail (please use my private mail [email protected]).
Thanks for your attention,
Luis Fernando Soeiro
Hi !! OC4J 9.0.3 developer's preview has most features of EJB 2.0. We are working on updating on our docs and samples for EJB 2.0
Please look at the following URL that has some How Tos on EJB 2.0 features such Local Interfacea, EJB QL, etc : http://otn.oracle.com/tech/java/oc4j/htdocs/oc4j-how-to.html#ejb
regards
Debu Panda
Oracle --------------------------
Luis Soeiro <mailto:[email protected]> <mailto:[email protected]>Type : Question Date : Apr 11, 2002 15:15 PT Hello
Some colleagues and I are trying to port a large project from JBOSS to OC4J. We used JBOSS 3.0 (beta) in order to evaluate EJB2.0 features and see if we could use it. We already have OC4J in production, but only as a JSP/Servlet container. The next step would be to deploy our EJB application to OC4J.
We have read the material and it is written that OC4J (developers preview) is EJB 2.0 compliant. However, the specific documentation and the examples don't show how to specify OC4J specifc XML files. We absolutely need CMR and Local Interfaces, because we don't have the time required to downgrade our JBoss EJB2.0 application to the EJB 1.1 specification. We have over 80 Session Beans and over 20 Entity Beans.
Is there anybody there that can confirm that OC4J developer's preview is really EJB2.0 compliant? If so, could you send me some pointers to information about OC4J container specifc deployment descriptors? The docs listed at the web site don't have EJB2.0 features listed, nor does the Oracle samples.
Thanks for your attention,
desperately,
Luis Fernando Soeiro

HI,
I worked out CMR and EJB-QL with single bean.
Using CMR, it is possible to get one bean reference through other bean, but
When I tried EJB-QL with bean to bean navigation then I run into problem.

Global transactions in OSB and EJB 2.1

Hi,
My team is working in a SOA service based on OSB 11g (11.1.1.5) using DB JCA Adapter and EJB 2.1 over WLS 10g(WLI environment). The logic of the service works in this way:
1. A table in a database (XE) is polled by the DB Adapter which starts the service (1 row = 1 message).
2. The message contains a collection of items to be inserted in another Oracle database.
Once a message/row is picked, and after some steps (logging, validation,etc), there is a for..each action which extracts each item of the collection and executes a service callout action to a business service.
3. This business service uses EJB protocol to call an EJB (2.1 + WLS Extensions). The EJB is deployed in another domain (WLS 10.3.0/10g and Oracle BEA drivers) and only executes an store procedure with the parameters based on the message and inserts these values in a table.
4. Once the for...each finishes, there is a call to another proxy service which marks the message/row as "processed" in the source table. This update is done via DB JCA also.
5. In case of an error, the error handler of the proxy service calls the proxy service mentioned above to mark the row as "Failed" (in fact there is a retry mechanism, but it's not important for now).
The service requires to work inside a global transaction. The main requirement is that the collection of items should be processed as "All or None", so basically we're using the options to manage the global transaction. However, the problem is that it's failing to rollback the whole insertion of items when an error is simulated. It only rolls back the last insertion/execution of SP.
Additionally, the proxy service that should mark the row as FAILED, never updates this one, and the tables stay locked until we modify one of the store procedure in order to avoid the simulated error and commit the transaction.
The EJB uses WLS extensions with the annotations to "transaction required". The proxy service has the option transaction required also. The database drivers are all XA and we're testing against Oracle11g XE (however, the EJB destiny will be Oracle 8i in production).
We have tried different alternatives, splitting the logic in different proxies (Proxy services for JCA, Proxy with For Each for EJB, etc), isolating the specific part with the EJB call, without success.
The security between domains is set as Global Trust.
Do you have any idea, example or suggestion about this problem? Is EJB really supported in Global Transactions and XA?
Thanks in advance.

where do you find the J2EE Connector 1.5 compliant
Resource Adapter?I wrote the compliant adapter myself. Hey Steve,
Were you able to find a solution for this problem. I am struggling with the same problem with the RI Beta implementation.
Sandeep

ADF and EJB. Why so little samples / information

Hi All,
I was wondering if other JDev / ADF developers have the same feeling as me in regards to ADF / EJB.
There is barely enough information and examples on using ADF with EJB. Seems that most examples and blogs are related to BC instead.
I was reading an article (sorry, don't have the link to it) not long ago that an Oracle Executive was asked if BC or EJB was Oracle's future and EJB was the answer. However, that doesn't seem to be the what most blogs and sample are about.
I know that BC has tight integration with ADF, but it's not a standards based back-end framework. We are locked in the ADF UI for all of our development, but not touching BC at all. All code is EJB compliant.
So, my request is:
- comments? do other developers out there feel the same way?
- bloggers, the great articles from "Frank Nimphius" and "Andrejus Baranovskis", not to mention others, can you guys post a little more on using ADF with EJB?
BTW: great article on that "http://www.oracle.com/technology/products/jdev/tips/fnimphius/ControlHintsWithPojos/controlHintsWithPojos.html" (How-to find and set control hints on POJO entities in bean Data Controls)
Thanks and Regards
Jonny Oenning

Hi!
I rised this issue long time ago - with TP3 I noticed regression in EJB/JPA support with ADFm (binding layer as referred by Shay). Following the development, I draw this conclusions:
1. Oracle is oriented toward J2EE standards, including the strategic orientation to EJB/JPA. The team that managed JDev 11g initial development phases was oriented toward EJB (but was replaced/fired sometime between TP2 and TP3).
2. Oracle decided that FMW 11g stack products as well as EBS migration from PL/SQL to EJB is not feasible in short time frame (I think that was poor judgment). So, the BCs got the push over the EJB and TP3/4 was biased toward BCs. Even the default Fusion technology stack is changed - in TP1/2 the Fusion Web project was ADF RC + EJB buy default and then changed to ADF RC + BC4J. Also the development guides were "rephrased".
3. As BC4J are proprietary Oracle technology, the are lacking many J2EE standard features and many strong points of the modern multi-tier architecture. Many developers are witnessing the performance / scalability issues as the BC4J are basically a mutant: they are SQL based concept wrapped into EJB for deployment! But they are not relaying on proven scalable J2EE technologies (like JPA/JTA, object caching etc.). They are trying to reinvent the wheel, decalratively offering the heaven of J2EE multi-tear architecture to old fashion SQL-focused architects/developers. But it is just a marketing - the truth is that BC4J are not and cannot be the replacement for proven J2EE architecture. They are trying to mimic the concepts of J2EE (like object-entity mapping, like JTA/JPA, like scalability and caching, transparent web-services exposition etc.) but they are lagging behind even J2EE 1.4 and we are facing the J2EE 6 in few months!
4. Oracle is aware that EJB is the future but they are trying to bridge the gap between their legacy code written mainly in PL/SQL. So they developed and they are developing the JDeveloper 11g in fashin that should support and serve for their primary goals - migration of their own old PL/SQL based products to new, J2EE, world (of BEA!).
So, anyone who is expecting the that Oracle JDeveloper is what they are marketing (full scale J2EE IDE) - is going to waste some time and money waiting the Oracle to finish it's half-way migration from PL/QL and Forms/Reports to PL/SQL + ADF RC! In few years from now.
Thus, if you need efficiency in J2EE standards development - try something else than JDeveloper. Or, as suggested by Shay, don't use overmarketed ADFm as it is not compatible with EJBs in scalable / clustered deployment! Yes, that is proven issue (but I wont elaborate here as it is already well elaborated in this forum in another tread but the Oracle guys wisely neglected that issue).
And beside few very very old and for me useless blog entries (one of which is not working in 11g as you may read in comments) there will be no much support for EJBs in this release of JDeveloper - I can bet!
But, as final message to the public, I'm still stuck with JDev and EJBs as. When you develop you own patterns, it is still the best combination for developing the scalable, high performance apps on Oracle FMW 11g platform - mandatory including several grid technologies that are making the difference in scalability of true J2EE apps and quasi-J2EE "Fusion" apps based on BC4Js "silently" wrapped in EJBs for deployment.
Regards,
PaKo

CORBA and EJB

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