[CATALINA] Unknown protocol jndi: && MalformedURLException

["Bordet, Simone" <Si...@compaq.com>]

Hello all,

I encounter the following problem using Catalina 4.0b3-4 (while it was
working with Tomcat 3.2.x).
I deploy a war containing a servlet and a javabean. From a JSP I invoke the
servlet, that creates the javabean, that invoke a remote object via RMI
calling a method that takes an instance of a parameter class as method
argument.
In the war I have the servlet in a jar under WEB-INF/lib, and the javabean,
the stub, and parameter classes under WEB-INF/classes.
Inside the javabean, I lookup JNDI and obtain a java.lang.reflect.Proxy that
at the end calls the java.rmi.Remote object passing it the argument.

Now, if inside the proxy I call RMIClassLoader.getClassAnnotation on the
parameter class, I obtain:
jndi:/WEB-INF/classes/ jar:jndi:/WEB-INF/lib/xxx.jar!/

This class annotation is written to the RMI stream and when it comes to the
RMI server side, I got the MalformedURLException: unknown protocol jndi.
Of course the RMI server side does not know how to handle the jndi: protocol
of Catalina, and it does have the parameter class in its classpath. Also,
the RMI server does not run with the SecurityManager.

Another thing that bothers me is that I expected the context classloader to
load the class in the RMI server (from its classpath), discarding the
annotated codebase contained in the RMI stream, but this is not the case
(but maybe I'm missing something).
Furthermore I got a workaround: if I wrap all arguments into a wrapper
class, and then the wrapper object into a java.rmi.MarshalledObject, then
the whole rigmarole works, ie the call arrives to the server (since
java.rmi.MarshalledObject is not loaded from WEB-INF/classes or WEB-INF/lib
I have no protocol problems) and then when I call MarshalledObject.get() the
context classloader loads correctly the classes from the RMI server
classpath.

Finally this problems happens also when the "RMI server" is JBoss, as
recently pointed out in the JBoss' mailing list.

Any thoughts ?

TIA

Simon

Re: [CATALINA] Unknown protocol jndi: && MalformedURLException

["Craig R. McClanahan" <cr...@apache.org>]

Simon,

I'm going to do some internal checking within Sun on this as well -- I've
only played with RMI a little.  The context class loader inside Catalina
web apps is the class loader for that web application, so there might be
conflicts with RMI's assumptions.

I also have a question -- if the classes of the objects you are passing
are themselves loaded from a parent class loader (i.e. from
$CATALINA_HOME/lib) instead of the web app class loader, do you still have
to do the marshalling workaround?  I would have expected those classes to
be annotated with a "file:" URL, because they are loaded by a class loader
that uses "file:" URLs for its repository.

Craig

On Fri, 11 May 2001, Bordet, Simone wrote:

> Hello all,
> 
> I encounter the following problem using Catalina 4.0b3-4 (while it was
> working with Tomcat 3.2.x).
> I deploy a war containing a servlet and a javabean. From a JSP I invoke the
> servlet, that creates the javabean, that invoke a remote object via RMI
> calling a method that takes an instance of a parameter class as method
> argument.
> In the war I have the servlet in a jar under WEB-INF/lib, and the javabean,
> the stub, and parameter classes under WEB-INF/classes.
> Inside the javabean, I lookup JNDI and obtain a java.lang.reflect.Proxy that
> at the end calls the java.rmi.Remote object passing it the argument.
> 
> Now, if inside the proxy I call RMIClassLoader.getClassAnnotation on the
> parameter class, I obtain:
> jndi:/WEB-INF/classes/ jar:jndi:/WEB-INF/lib/xxx.jar!/
> 
> This class annotation is written to the RMI stream and when it comes to the
> RMI server side, I got the MalformedURLException: unknown protocol jndi.
> Of course the RMI server side does not know how to handle the jndi: protocol
> of Catalina, and it does have the parameter class in its classpath. Also,
> the RMI server does not run with the SecurityManager.
> 
> Another thing that bothers me is that I expected the context classloader to
> load the class in the RMI server (from its classpath), discarding the
> annotated codebase contained in the RMI stream, but this is not the case
> (but maybe I'm missing something).
> Furthermore I got a workaround: if I wrap all arguments into a wrapper
> class, and then the wrapper object into a java.rmi.MarshalledObject, then
> the whole rigmarole works, ie the call arrives to the server (since
> java.rmi.MarshalledObject is not loaded from WEB-INF/classes or WEB-INF/lib
> I have no protocol problems) and then when I call MarshalledObject.get() the
> context classloader loads correctly the classes from the RMI server
> classpath.
> 
> Finally this problems happens also when the "RMI server" is JBoss, as
> recently pointed out in the JBoss' mailing list.
> 
> Any thoughts ?
> 
> TIA
> 
> Simon
>