UIMA Ruta classloader issues

[Georg Bonczek <ge...@tum.de>]

Hi,

I'm having difficulties setting up an AnalysisEngine containing JCas 
Annotators and a Ruta script that calls extension functions using the 
Play framework. Since the Play framework uses its own hierarchy of 
classloaders, the system classloader somehow does not find the extension 
classes.

When creating the type system and descriptors for the Ruta script, I can 
pass the classloader used by the framework through the RutaBuildOptions. 
But when creating an AnalysisEngine, the 
initializeExtensionWithClassPath() method in the RutaEngine class does 
only use Class.forName(each) to instanciate the extensions. When 
replacing this call with

this.resourceManager.getExtensionClassLoader().loadClass(each);

and setting the manager's classloader to the one used by the framework, 
the extensions get instanciated and the execution of the rule succeedes. 
Is this behaviour expected and is there a way around this without having 
to change the RutaEngine class? Please find the relevant parts of my 
source code here: 
https://gist.github.com/zekrg/42d0bea5a2c9c561d152a6df268318d5.

Thanks for your help.

Re: UIMA Ruta classloader issues

[Peter Klügl <pe...@averbis.com>]

Hi,


short answer: this should be fixed in RutaEngine


Ruta did not support special classloader in previous version (like
PEARs), but obviously not all functionality has been fixed.

The classloader in RutaBuildOptions in used only for building the
descriptors, like finding imports by name when creating the type system
descriptor, in special environments like in a maven build process or
within a eclipse plugin.


Thanks for reporting this. I'll open a Jira issue for it and fix it ASAP.


Best,


Peter


Am 21.09.2017 um 16:30 schrieb Georg Bonczek:
> Hi,
>
> I'm having difficulties setting up an AnalysisEngine containing JCas
> Annotators and a Ruta script that calls extension functions using the
> Play framework. Since the Play framework uses its own hierarchy of
> classloaders, the system classloader somehow does not find the
> extension classes.
>
> When creating the type system and descriptors for the Ruta script, I
> can pass the classloader used by the framework through the
> RutaBuildOptions. But when creating an AnalysisEngine, the
> initializeExtensionWithClassPath() method in the RutaEngine class does
> only use Class.forName(each) to instanciate the extensions. When
> replacing this call with
>
> this.resourceManager.getExtensionClassLoader().loadClass(each);
>
> and setting the manager's classloader to the one used by the
> framework, the extensions get instanciated and the execution of the
> rule succeedes. Is this behaviour expected and is there a way around
> this without having to change the RutaEngine class? Please find the
> relevant parts of my source code here:
> https://gist.github.com/zekrg/42d0bea5a2c9c561d152a6df268318d5.
>
> Thanks for your help.
>
>