Cannot Start Java Class in Camunda BPM

Hello, I’m getting the following error when I try to run a task in Camunda BPM Run.

The process could not be started. : Cannot instantiate process definition SimpleDemo:2:f70332d9-b706-11ea-bc59-caf43f70e38a: ENGINE-09008 Exception while instantiating class

I build the .WAR file in Eclispe and put it in the configuration/resources folder, but I’m still getting this error. Where am I supposed to place the .WAR file in order for Camunda BPM Run to find the Java Classes?

Thank you

Hi @Mike_Ninov,

you are mixing two approaches: shared and standalone process engine. Camunda Run is an example for a standalone process application and didn’t support process applications bundled as war files.

Niall explained in his video how to deploy processes to Camunda Run: https://www.youtube.com/watch?v=l-sCUKQZ44s.

If you want to keep the process application, you have to use the Camunda Tomcat distro.

Hope this helps, Ingo

@Igno_Richtsmeier That makes more sense. I was able to get the .war file to work on a wildfly distribution. I am wondering though, how do you make use of more complex logic in a Java Class when using BPM Run? I am. trying to build a basic demonstration to show the capabilities of Camunda, but I’m having a hard time figuring out how to have external tasks integrated with BPM. Thanks again.

Hi @Mike_Ninov,

Camunda Run is built to support the external task pattern (https://docs.camunda.org/manual/develop/user-guide/process-engine/external-tasks/), where the task implementation is part of your micro services surrounding the Camunda process engine.

In your case you should decide if you want to follow the classic (some name it old school) approach of a central workflow engine responsible to call all the services (that’s what wildlfly distro serves) or the hipster microservice approach with a bunch of independend services which should serve one or many defined business processes (Camunda Run should be your choice).

But is not an either-or, there are many use cases inbetween both approaches.

Hope this helps, Ingo