Dependencies to a fixed ExpressionFactory


we would like to use the dmn-engine within our multi-project architecture.
I include the camunda-engine-dmn, 7.7.0 in maven:


Compiling and first calls wer leading to no problems, dmn-example.xml was correctly executed! So war everythings looks nice. But the first call to a jsp-page creates following error and the application stops:

//Login with method execute.
2017-07-08 20:29:02,852 ERROR [http-bio-8090-exec-3] [Sk=170708-202902124_890@50, Nutzer=guest] org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/servicestelle].[jsp] Servlet.service() for servlet jsp threw exception
java.lang.ClassCastException: de.odysseus.el.ExpressionFactoryImpl cannot be cast to javax.el.ExpressionFactory
at javax.el.ExpressionFactory.newInstance( ~[el-api.jar:2.2.FR]
at javax.el.ExpressionFactory.newInstance( ~[el-api.jar:2.2.FR]

The problem are the different used El-Implementations? How can we solve the problem when we include camunda-engine-dmn-7.7.0.jar. The dependencies is camunda-engine-dmn-7.7.0.jar to juel-impl are fixed and other moduls
in our project are fixed to tomcat-el-api.

I tried to exclude the juel-api but without success. :frowning2:
Does anybody has an idea how to solve the problem?

Best regards,


Hi @humphrey,

I’m not sure about the problem but if you can’t embed the DMN engine then maybe it’s an option to run the DMN engine in parallel and communicate via the Rest Api.

Best regards,