KAON2 and Protégé

KAON2 is the Karlsruhe Ontology infrastructure. It is an industry strength reasoner for OWL ontologies, pretty fast and comparable to reasoners like Fact and Racer, who gained from years of development. Since a few days KAON2 also implements the DIG Interface! Yeah, now you can use it with your tools! Go and grab KAON2 and get a feeling for how good it fulfills your needs.

Here's a step to step description of how you can use KAON2 with Protégé (other DIG based tools should be pretty the same). Get the KAON2 package, unpack it and then go to the folder with the kaon2.jar file in it. This is the Java library that does all the magic.

Be sure to have Java 5 installed and in your path. No, Java 1.4 won't do it, KAON2 builds heavily on some of the very nice Java 5 features.

You can start KAON2 now with the following command: java -cp kaon2.jar org.semanticweb.kaon2.server.ServerMain -registry -rmi -ontologies server_root -dig -digport 8088 Quite lengthy, I know. You will probably want to stuff this into a shell-script or batch-file so you can start your KAON2 reasoner with a simple doubleclick.

The last argument - 8088 in our example - is the port of the DIG service. Fire up your Protege with the OWL plugin, and check in the OWL menu the preferences window. The reasoner URL will tell you where Protege looks for a reasoner - with the above DIG port it should be http://localhost:8088. If you chose another port, be sure to enter the correct address here.

Now you can use the consistency checks and automatic classification and all this as provided by Protege (or any other Ontology Engineering tool featuring the DIG interface). Protégé tells you also the time your reasoner took for its tasks - compare it with Racer and Fact, if you like. I'd be interested in your findings!

But don't forget - this is the very first release of the DIG interface. If you find any bugs, say so! They must be squeezed! And don't forget: KAON2 is quite different than your usual tableaux reasoner, and so some questions are simply not possible. But the restrictions shouldn't be too severe. If you want more information, go to the KAON2 web site and check the references.