Hi kris,
Thanks for this info.
I have further doubts.

(myclass) PortableRemoteObject.narrow(...)   ..............................1
In above case even if I give narrow fn the Object, and the required class,
still I have to downcast it to myclass. In CORBA, there will be appropriated
helper class generated and you call the ||ar fn of the helper class.

i.e.
myclass a =helper.narrow(Object);
...............................................2

There is no need to downcast.

Now suppose my client is not java or  C++ and no casting is allowed (client
written in other language say smaltalk or python) then (1) will fail. Am I
right ??

--Ashwani




----- Original Message -----
From: "Ramakrishna N" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, October 10, 2002 1:05 PM
Subject: Re: PortableRemoteObject.narrow


> To be more clear,
>        The object(stub) that is in the JNDI Naming space has been
> implemented in a language that is different from JAVA but a Java
> Application(EJB Container) wants to make use of it, had it been java a
> simple cast would have served the purpose but when the remote object(stub)
> has been implemented in a different language and was made available
through
> Corba, there is much more one has to do (cast wont work) to check if that
> exported object can act as our EJBHome and then convert the stub into a
> class which can act like  a normal java-stub and this is exactly what
> happens in the implementation of the the PortableRemoteObject.narrow(...)
> method, after it checking if casting would work.
>        Since we dont know the type of the exported stub we need to have a
> util method which can tell us if that exported stub can act as our EJBHome
> Stub and then to convert it accordingly and that method is what our
> PortableRemoteObject.narrow(...)
>        Hope this helps !
>
> Regards,
> kris
>
> -----Original Message-----
> From: Ashwani Kalra [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, October 09, 2002 4:03 PM
> To: [EMAIL PROTECTED]
> Subject: PortableRemoteObject.narrow
>
>
> Hi,
> Why its asked to use
> PortableRemoteObject.narrow(home, home.class)
>  instead of just downcasting. The specs mention it is due to rmi-iiop
> compatibility.
> Can any body explain in more details about it.
>
> TIA
> Ashwani Kalra
>
>
===========================================================================
> To unsubscribe, send email to [EMAIL PROTECTED] and include in the
body
> of the message "signoff EJB-INTEREST".  For general help, send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
>
>
===========================================================================
> To unsubscribe, send email to [EMAIL PROTECTED] and include in the
body
> of the message "signoff EJB-INTEREST".  For general help, send email to
> [EMAIL PROTECTED] and include in the body of the message "help".
>

===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff EJB-INTEREST".  For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".

Reply via email to