Fuseki how to add Pellet reasoner

Question

I want to use pellet reasoner with my Fuseki 2.3.1

First: I added Pellet reasoner to my config.ttl as this:

ja:reasoner
        [ ja:reasonerClass
           


        

Answer 1

The error you have is

expected class org.apache.jena.reasoner.ReasonerFactory, but had class org.mindswap.pellet.jena.PelletReasonerFactory

I'm no expert but it looks like the Pellet factory for Jena currently in your classpath does not match the expected class.

Which version of Jena comes with Fuseki, and which version is currently used by Pellet?

Answer 2

Solution: Use openllet instead. Just change to ja:reasonerClass "openllet.jena.PelletReasonerFactory" in the config file, and download the openllet distribution and other jar files needed to the classpath.

Explanation:The error

expected class org.apache.jena.reasoner.ReasonerFactory, but had class org.mindswap.pellet.jena.PelletReasonerFactory

is caused by that the pellet's org.mindswap.pellet.jena.PelletReasonerFactory implements the old interface (com.hp.hpl.jena.reasoner.ReasonerFactory) which is different from the interface used in Fuseki (org.apache.jena.reasoner.ReasonerFactory).

The openllet's openllet.jena.PelletReasonerFactory implements the correct interface (org.apache.jena.reasoner.ReasonerFactory).

Check their source code:

openllet's PelletReasonerFactory.java

pellet's PelletReasonerFactory.java