Ejb, servlets, & customer libraries

Hello,
I'm in the process of upgrading from 5.1 to 6.1 and having some
interesting issues regarding the various interdependent chunks of code.
In 5.1 I have most of my shared code under <server>/serverclasses, and
the servlet code under <server>/servletclasses. I've also got an EJB
that uses some of the code in the serverclasses directory, and its being
there seems to make it available at runtime to the EJB's classloader.
Meanwhile, in order to make the EJB's home interface available to the
servlet code at run time, the only solution I found was to include the
jar file in the classpath handed to the java runtime in the startup
shell script.
Now, in 6.1 things have changed somewhat and i'm frankly not sure what
the hell to do. I found someone had posted an article talking about
bundling things in a .ear file. Honestly, I didn't really get it. I
don't see why changing the extension on the jarfile is going to help at
all.
Anyway, this is my question: How can I make code available as a custom
library that is available to the servlet run time, and to my EJB
deployments?
Here's my other question: If the EJB code is only in the .jar ( or
whatever ) file that the EJB is packaged in, how exactly does the
servlet runtime know about the home interface? Just deploying the bean
doesn't seem to do the trick. Honestly, this seems like a pretty big
design flaw in the EJB spec to me.
thanks
noah

You may find these 2 articles helpful:
http://www.onjava.com/pub/a/onjava/2001/06/26/ejb.html
http://www.onjava.com/pub/a/onjava/2001/07/25/ejb.html
Noah Couture <[email protected]> wrote:
Hello,
I'm in the process of upgrading from 5.1 to 6.1 and having some
interesting issues regarding the various interdependent chunks of code.
In 5.1 I have most of my shared code under <server>/serverclasses, and
the servlet code under <server>/servletclasses. I've also got an EJB
that uses some of the code in the serverclasses directory, and its being
there seems to make it available at runtime to the EJB's classloader.
Meanwhile, in order to make the EJB's home interface available to the
servlet code at run time, the only solution I found was to include the
jar file in the classpath handed to the java runtime in the startup
shell script.
Now, in 6.1 things have changed somewhat and i'm frankly not sure what
the hell to do. I found someone had posted an article talking about
bundling things in a .ear file. Honestly, I didn't really get it. I
don't see why changing the extension on the jarfile is going to help at
all.
Anyway, this is my question: How can I make code available as a custom
library that is available to the servlet run time, and to my EJB
deployments?
Here's my other question: If the EJB code is only in the .jar ( or
whatever ) file that the EJB is packaged in, how exactly does the
servlet runtime know about the home interface? Just deploying the bean
doesn't seem to do the trick. Honestly, this seems like a pretty big
design flaw in the EJB spec to me.
thanks
noah--
Dimitri

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Hi,
What is the best way to call an EJB from a JSP? We are using Weblogic 7.0(moving to 8.1 beta). WE have a form on a JSP that needs to get data from an EJB. Our flow goes from JSP --> Controller servlet or tag library -->EJB "Bean" Controller ---> EJB. The specfic EJB we need to populate drop downs and fields will be called by a bean controller. Is it better to call the bean controller using a tag library in the jsp or go to the controller servlet to get the data? If servlet is the answer, where do I lookup the EJB Home and call the create from within the servlet? Any help would be greatly appreciated!!
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So is there any good approach to debug?
email: [email protected]

Hi Marvin,
If the EJB cannot be deployed to the embedded AS, then you should probably use remote debugging to debug the servlet and EJB in the stand-alone AS.
Look in the Help for topics about remote debugging the OC4J application server. (I'd give you the exact topic title, but I'm at home for the holidays and I don't have the latest JDev on this machine.)
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1. Launch the AS in debug mode by inserting some debugging options on the command line used to start up the AS.
If you are using OJVM, then the debugging options are
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If you are using another JVM (for example HotSpot), then the debugging options are
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Best IDE to develop EJB/Servlet development with WebLogic

Hi,
I am prepearing a recommendation for our company's standard Java development
environment. I would appriciate any comment you guys might have on the best
IDE that supports J2EE and EJB and Servlet development that integrates with
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experince/comment on any of those ?
Thanks
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I would recommend the products coming from Webgain. They offer the product
suite surrounding visual cafe.
Thanks,
Michael
Michael Girdley
Product Manager, WebLogic Server & Express
BEA Systems Inc
Farhang Kassaei <[email protected]> wrote in message
news:8fs706$643$[email protected]..
Hi,
I am prepearing a recommendation for our company's standard Javadevelopment
environment. I would appriciate any comment you guys might have on thebest
IDE that supports J2EE and EJB and Servlet development that integrateswith
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Thanks
Farhang

Ejb servlet application

i am using orion.
i have an ejb app running.. i can connect to it from an external client.
however, as soon as i turn the client into another ejb app that is just a servlet, i get ClassCastException when getting the remote interface.
any ideas?

i think it's due to the fact that your Home is not only in the classpath of the container but in the classpath of the servlet engine too. so when you're trying to get the home, a ClassCastException is thrown bcz the home you got has not the same version as the home in servlet engine (uid).
hope it helps.

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EJB. One such situation was invoking an EJB running in WebLogic 6.1 from an
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invoking EJB's.
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RMI over HTTP or some other method? Are there other situations where a
Servlet bridge would be useful?
In the case of applets, it seem like a Servlet bridge would be nice because
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example the InitialContext class wasn't included in the standard edition
until 1.3.
Thanks,
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Bob Lee <[email protected]> wrote:
I've come across suggestions a couple of times to use a Servlet bridge to an
EJB. One such situation was invoking an EJB running in WebLogic 6.1 from an
application running in WebLogic 5.1. Other situations have been for applets
invoking EJB's.
Two questions. When should you implement a Servlet bridge rather than using
RMI over HTTP or some other method? Are there other situations where a
Servlet bridge would be useful?
In the case of applets, it seem like a Servlet bridge would be nice because
you wouldn't need to provide the EJB client classes to the applet. For
example the InitialContext class wasn't included in the standard edition
until 1.3.You wouldn't need to provide WebLogic classes - you need several megabytes of them
on the client side in order to use T3.
Thanks,
Bob--
Dimitri

Workshop 8.1 Calling EJB from Custom Authentication Provider

I am writing a custom authentication provider that runs on Weblogic Server 8.1 and also on Workshop 8.1. Everything is packaged into a jar file that I put into the mbeantypes directory. From the authentication provider I want to get an EJB home that is on another Weblogic 8.1 server.
Loading the home from the Weblogic server works great. But in Workshop I get a ClassCastException from the PortableRemoteObject.narrow() call.
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Any ideas?
Thanks,
Mark

Issue has been resolved.
The reason I've forgotten about Value Object that is being returned by Remoute method to put them into classpath of Authenticator Provider

Ejb + servlet + jsp

Hallo everybody,
i try to develop an application with servlet jsp and ejbs but i don't have enough information about this thema.
for example i want to make a simple login szenario :
user type the name and passwd and the system contact with the db and show a wellcome page if the login is succesfull and an error page if the login is unsuccessfull.
which component does was??
the first page can be a html form and post the name and passwd to a servlet.
in this case servlet can make a connection with the DB and can forward the user to next page or error page. BUT where should i use EJB? can i realize the db connection with ejb ? if yes how can interact the servlet with the ejb and how can i store the information (for example address of user) which i have taken from the DB?
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Thanks for the antwort
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and the second part is my bigger problem :)
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Perhaps
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EJB, Servlet, JSP help

I have built a small application which creates/maintains company divisions following the MVC design pattern.
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Hi,
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Good luck,
Dan
I have built a small application which
creates/maintains company divisions following the MVC
design pattern.
I now want to move the methods which create,update,
add objects out of the controller possibly into the
Model servlet. This I hope would allow other parts of
the application (not yet built) to manipulate division
objects and not have to do this through the
Contrroller which is used to call the JSP and present
data.
I am wondering whether I should do this, or whether i
should just move straight to Entity Java Beans, which
I believe handle all interfaces with the database.
If you reckon this is the correct way forward can you
tell me where I can see a good example i.e. has EJB
which handle all dtabase communication and can talk to
the controller servlet and the jsp.

EJB & Servlet deployment in Clustered Env.

          Hi,
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          etc etc).
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          If I do that, the request is not routed to other servers. Since the servlet finds
          the EJB locally, it never goes to the other servers, regardless of the algorithm.
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          Sharad


If the ejb is deployed on the server that is looking for the ejb, then it
          won't go network to use the ejb. That is a "big" WL optimization, and helps
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          If you want to segregate the ejb and web functionality, you should probably
          consider running two distinct clusters (in 5.1 parlance).
          I suggest putting web and ejb together though and clustering that. Latency
          is lower. Scalability is not particularly affected. Configuration is much
          simpler.
          Peace,
          Cameron Purdy
          Tangosol, Inc.
          http://www.tangosol.com
          +1.617.623.5782
          WebLogic Consulting Available
          "Sharad Joshi" <[email protected]> wrote in message
          news:[email protected]...
          >
          > Hi,
          >
          > I have made a cluster of 3 weblogic servers. I would like to send a
          request to one
          > server (e.g. http://myserver1:7001/TestServlet). The servlet utilizes an
          EJB which
          > is not located and not deployed on myserver1 , but on other 2 servers in
          the cluster.
          > The algorithm is round-robin. It gives me a lot of errors (Impl... classes
          not found
          > etc etc).
          >
          > Do I have to deploy everything on all the servers?
          > If I do that, the request is not routed to other servers. Since the
          servlet finds
          > the EJB locally, it never goes to the other servers, regardless of the
          algorithm.
          > I have set up the "home-is-clusterable" and all other relevant properties
          for EJB
          > deployment.
          >
          > Any ideas??
          >
          > Sharad

Arduino ino with custom libraries

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Except that it does not appear in my "User Defined" option, hence the reason for me trying to find it in "Other Libraries." Sorry I did not explain that. That's why I'm bothered by this. This is very unusual.

Servlet jndi lookup to remote EJB, servlet and EJB not in the same application

Hi,
I think that the subject explain my problem.
I have Oracle IAS9i 9.0.2.0.0, and JDeveloper 9.0.2.829
I have deployed and EJB in IAS9i and i want to use from the developer machines, which have JDeveloper.
how can i to do remote calls from JDeveloper?.
I have modifed the orion-application.xml, and added remote=true.
I have modifed the rmi.xml and added the hosts where the Jdeveloper placed.
Any ideas?
Thanks and cheers
P.D The app server and jdeveloper are in the same net.
if it is posible replys me to [email protected] too.

Steps to access a remote EJB from within OC4J
++++++++++++++++++++++++++++++++++++++++++++++
1) Deploy EJB application (ApplicationRemote) to remote container (REMOTE)
"java -jar admin.jar -deploy ormi://REMOTE.hostname:REMOTE.port REMOTE.username REMOTE.password -deploy -file ApplicationRemote.ear
-deploymentName ApplicationRemote"
2) Ensure that local application (ApplicationLocal) has ejb-ref tags for remote EJBs accessed (in web.xml or ejb-jar.xml)
3) Deploy to local container (LOCAL) an empty application (ApplicationEmpty) with the same name as the remote application (ApplicationRemote)
"java -jar admin.jar -deploy ormi://LOCAL.hostname:LOCAL.port LOCAL.username LOCAL.password -deploy -file ApplicationEmpty.ear -deploymentName
ApplicationRemote"
5) Deploy local application (ApplicationLocal) to local container (LOCAL)
"java -jar admin.jar -deploy ormi://LOCAL.hostname:LOCAL.port LOCAL.username LOCAL.password -deploy -file ApplicationLocal.ear -deploymentName
ApplicationLocal"
4)Restart local container
ApplicationEmpty should consist of just an application.xml file - no modules. The same file can be deployed with different application names for all the remote
applications that must be accessed.
ApplicationLocal should access the remote EJB by using the following JNDI properties
java.naming.factory.initial = "com.evermind.server.rmi.RMIInitialContextFactory"
java.naming.provider.url = "ormi://REMOTE.hostname:REMOTE.port/ApplicationRemote"
java.naming.security.principal = "REMOTE.username"
java.naming.security.credentials = "REMOTE.password"
regards
Debu Panda

Ejbs - Included AQ libraries

I'm trying to deploy an ejb using JDeveloper 3.1.1.2 into Oracle 8.16 which uses the following packages:
oracle.aurora.jndi.sess_iiop.*;
oracle.jms.*;
oracle.AQ.*;
I get ClassNotResolved exceptions at the "Generating EJBHome and EJBObject on the server..." stage.
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When I query the generated jar, I cant see that AQ classes have been added.
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Hope that helps.

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