Tutorial: Ontology Development
Contents
Step 1: Ontology Plug-in
Ontologies are encapsulated in OSGi bundles. In eclipse we develop them as equinox plug-ins. It contains ontology sources (graph/*.pgraph), compiled graph file (graph.tg), and Java resource files (src and bin).
Open a New Plug-in Project wizard:
- Select File >> New >> Plug-in Development >> Plug-in Project
Our organization is Acme Software ltd and from there is our plug-in name derived, com.acme.movie.ontology. Insert that as project name. In the following page you should know that this plugin does not contribute to UI, does not need activator or isn't a rich client application.
Setup Graph Building Nature
First, Make sure you have installed Graph Compiler. Next, add Graph builder into the project nature.
- "com.acme.movie.ontology"' >> Context Menu >> Configure >> Add graph compilation
Also create directory called graphs, and there a file Movie.pgraph.
Configure MANIFEST.MF
Your ontology well depend on Layer0, so open META-INF/MANIFEST.MF in a editor and add org.simantics.layer0 to plug-in dependencies.
Also, you are going to
- Export package com.acme.movie.ontology
Your MANIFEST.MF should look like this.
Manifest-Version: 1.0 Bundle-ManifestVersion: 2 Bundle-Name: Ontology Bundle-SymbolicName: com.acme.movie.ontology Bundle-Version: 1.0.0.qualifier Bundle-Vendor: ACME Bundle-RequiredExecutionEnvironment: JavaSE-1.6 Require-Bundle: org.simantics.layer0;bundle-version="1.0.0" Export-Package: com.acme.ontology
Developing the ontology
Open Movie.pgraph and start editing.
As you are using Layer0 concepts, it is a good idea to capture its namespace:
L0 = <http://www.simantics.org/Layer0-1.0>
Your acme company has a namespace which is used . You are creating a new one so it must be stated.
<http://com.acme> : L0.Library @L0.new
The ontology has a representing resource, an instance of L0.Ontology. Don't forget to add stub-compiler metadata L0.HasResourceClass.
Movie = <http://com.acme/Movie-1.0> : L0.Ontology L0.HasResourceClass "com.acme.ontology.Movie"
