I'm getting a strange effect in Jena 2.5.5 (on linux) where I am playing around with the inference API. The following code is a stripped down version. I am creating an initially empty Model and a generic rule reasoner. I add a reflexivity rule for a certain statement. I attach the reasoner to the model to get an InfModel. Then I create ...
I need to keep a couple of [Jena] Models (OntModels, specifically) synchronized across a socket, and I'd like to do this one change at a time (for various reasons -- one being that each Statement added or removed from the OntModels is also adapting a JESS rule base.). I am able to listen to the add/remove events on the OntModels and the...
I'm new to the concept of ontology and Jena, so I'm not sure I'm phrasing this correctly.. I need to read a series of connected owl files (by namespace dependencies?) into an in memory Jena model (OntModel?) so inference can be run. How do I do this? Does the order of the files matter? Do I need to call a specific method to "run the ...
I have a Jena ontology model (OntModel) which I'm modifying programatically. This model was initially created using the default ModelFactory method to create an Ontology model (with no parameters). The problem was, as the program ran and the model was changed, the default Jena Reasoner would run (and run and run and run). The process ...
I want to add an xml:base declaration to an xml file in java. I currently have the xml output in an OutputStream that was generated by some third party code. The file starts out like this: <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns="http://www.mycompany...
This question relates to rcreswick's question on Serializing Jena OntModel Changes. I have Jena models on two (or more) machines that need to remain synchronized over sockets. The main issue that I need to address is that the models may contain anonymous nodes (bnodes), which can originate in any of the models. Question: Am I on the r...
Is there a way to override Jena's default method for generating anonymous node IDs? Ideally, I'd like to pass Jena a functor that would generate IDs so that I can make them globally unique (rather than just unique to the machine). The functor should be used whenever an AnonId is constructed. public interface IdGenerator { public St...
I need to query my local Hibernate managed datastore for persisted objects based on criteria where the relevant data for the WHERE clause is in the Linked Open Data cloud. Is there a way to read a Hibernate Session as RDF? If so, I can at least use the combined Dataset to decide what objects to retrieve from Hibernate. Preferably the s...
Hi all, Imagine the following Taxonomy (acyclic & directed graph): <my:Eukaryota> <rdfs:subClassOf> <my:Organism>. <my:Mammal> <rdfs:subClassOf> <my:Eukaryota>. <my:Primate> <rdfs:subClassOf> <my:Mammal>. <my:HomoSapiens> <rdfs:subClassOf> <my:Primate>. <my:Bacteria> <rdfs:subClassOf> <my:Organism>. <my:Escherichia> <rdfs:subClassOf> <m...
Hi, I'm new to Jena API's , I'm trying to figure out a way to get the base Namespace from a OWL ontology file, without using DOM or similar but just using the standard Jena's API. Is there such a way?? in an OWL file like how do I get the base namespace "http://www.owl-ontologies.com/Ontology1254827934.owl" a runtime?? Many many than...
I have a Jena URI Resource (Resource reference to an object where isURIResource() returns true). An example Resource URI is this: http://d.opencalais.com/er/company/ralg-tr1r/4ee13d20-b44f-3bce-98bc-49a303e72db5 If you open that in a web browser, you'll probably be given the HTML representation of the data: http://d.opencalais....
Hi Guys. I cannot understand how can I query dbpedia.org using Jena. In the tutorials like here(Listing 4) model is initialized as follows: // Open the bloggers RDF graph from the filesystem InputStream in = new FileInputStream(new File("bloggers.rdf")); // Create an empty in-memory model and populate it from the graph Model model = M...
Hello, we are designing a project that would listen to dialog between airport controllers and pilots to prevent runway incursions (eg. one airplane is taking off while other is crossing the runway). Our professor wants us to use Jena for knowledge base (or anything else but it should be some sort of rule-based engine). Inference is not t...
Hi, I would like to visualize an Ontology model created through Jena in Java. Is there an API which can help me out in this task ? Or at least a tutorial on the matter? Thanks in advance. ...
Im trying to create a Sqarql query using Jena to query dbpedia. The query is working when I use it with standalone tools (Twinkle) but when I plug it in this java code it returns an empty set. String sparqlQueryString1= "PREFIX dbont: <http://dbpedia.org/ontology/> "+ "PREFIX dbp: <http://dbpedia.org/property/>"+ ...
Hi, I have recently created a web project in Java using eclipse. I have a servlet which includes a timer task. This timer tasks calls the "writeList" method of an XML Writing class that I have created. This all works fine, and I have verified that it runs every minute using System.out. When I run my XML Writing class from within eclips...
Hi Everyone Just a small thing tonight; I was wondering how I could modify this query to show only bands with the name "kinks", I tried tagging = #kinks after dc:Band but got no results. Query SPARQL_QUERY = QueryFactory.create("" + "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>" + "PREF...
Hi, I want write query that allow to display all comment of all class in protege and other query to display specific comment please ,Iwante the answer quickly as soon as possible . ...
Hello I'm new to ontologies, my assignment is to create an ontology using Protege V4.0.2, (which I've done) and to create a website over that ontology(which I'm working on), i just need the basics on how to search the ontology using the Jena library I dont have any specifics because i haven't yet started. but i'm in a time crunch, and i ...
How can I get in Jena (Java language) result in UTF-8 format? My code: Query query= QueryFactory.create(queryString); QueryExecution qexec= QueryExecutionFactory.sparqlService("http://lod.openlinksw.com/sparql", queryString); ResultSet results = qexec.execSelect(); List<QuerySolution> list = ResultSetFormatter.toList(results); System....