One thing you might consider is making all your beans implement a Pingable
interface with one method, ping(). Then you can just cast each bean to
that interface and call the method.
Then it'd be typesafe - and probably faster, too, without the overhead of
the introspection.....
Yours,
Tom Copeland
[EMAIL PROTECTED]
703-317-5193
Fred Loney
<loney@SPIRITEDSW To: [EMAIL PROTECTED]
.COM> cc:
Sent by: A Subject: Re: Servlet creating an EJB
via reflection troubles
mailing list for
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<EJB-INTEREST@JAV
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11/16/2001 02:01
PM
Please respond to
Fred Loney
The stock response is to check your classpaths, descriptors, etc. but I
assume you did that. The intervention of a web container occasionally
introduces bizarre introspection class loader side effects. E.g. I
resolved a similar problem by moving the class to a different
package--don't ask me why that worked. Another problem similar to yours
is reported at
http://www.mail-archive.com/[email protected]/msg00665.html
. There was no resolution AFAIK, and related problems were reported by
others.
This is not a pat answer to your question, but it could provide a clue.
A start is to fiddle with the introspection--which classes & methods are
discoverable? I am reluctantly arriving at the conclusion that
introspection in servlet invocations is flaky and should be avoided.
Fred Loney
Spirited Software, Inc.
www.spiritedsw.com
----- Original Message -----
From: "Catalfano Anthony" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, November 16, 2001 10:06 AM
Subject: Servlet creating an EJB via reflection troubles
> I'm using VAJava 3.5 and WebSphere 3.5.
> I've asked all our EJB developers to supply a ping() method in any
deployed
> EJB so that we can test remote connectivity.
> I've written a main() method that works fine from within VAJava. Below
is
> the code.
> I've also written a servlet that is basically identical but gets the
> parameters for the PROVIDER_URL and beanJndiLookupName from the
request
> object.
> The strange thing is, I've taken the same exact code, pasted it into a
> servlet and it fails on the
> java.lang.reflect.Method m =
> obHome.getClass().getDeclaredMethod("create", new Class[0]);
> Even more strange is that the servlet used to work.
>
> Any ideas?
>
> String PROVIDER_URL = "iiop:///";
> String beanJndiLookupName = "some/bean/jndiName";
> java.util.Hashtable properties = new java.util.Hashtable(2);
> properties.put(javax.naming.Context.PROVIDER_URL,
PROVIDER_URL);
> properties.put(javax.naming.Context.INITIAL_CONTEXT_FACTORY,
> "com.ibm.ejs.ns.jndi.CNInitialContextFactory");
>
> // IBM name services
> javax.naming.InitialContext initContext = new
> javax.naming.InitialContext(properties);
>
> // get ref to remote interface
> Object objref = initContext.lookup(beanJndiLookupName);
>
> // get a ref to the home
> EJBHome obHome = (EJBHome)
> javax.rmi.PortableRemoteObject.narrow(objref, EJBHome.class);
>
> //invoke the create() method
> java.lang.reflect.Method m =
> obHome.getClass().getDeclaredMethod("create", new Class[0]);
> Object obj = m.invoke(obHome, new Object[0]);
>
> m = obj.getClass().getDeclaredMethod("ping", new Class[0]);
> Object pingObj = m.invoke(obj, new Object[0]);
> System.out.println(pingObj.toString());
>
>
> Anthony Catalfano
> Information Technology Analyst
> Deere & Company
> 309-748-5201
>
>
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