Hi i am new to Jena stuff, Couple of months ago i had used ARC and RAP (both PHP related). I now want to work with RDF on Java platform. I have tried quite a bit with Jena. I now know how to create resources, properties, and add them to model etc..
One thing i could not figure out is the extraction of RDFa which is embedded inside HTML. So could you please provide some sample code snippet for extracting RDFa from HTML?? I saw some page saying to use GRDDL, i tried that but got following error : log4j:WARN No appenders could be found for logger (com.hp.hpl.jena.sparql.mgt.ARQMgt). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info. Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory at com.hp.hpl.jena.grddl.impl.GRDDL.<clinit>(GRDDL.java:830) at com.hp.hpl.jena.grddl.GRDDLReader.read(GRDDLReader.java:47) at com.hp.hpl.jena.rdf.model.impl.ModelCom.read(ModelCom.java:241) at HelloRdfWorld.main(HelloRdfWorld.java:21) Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) ... 4 more Code : Model model = ModelFactory.createDefaultModel(); model.read("file:///C:/wamp/www/SemSearch/html/sample.html", "GRDDL"); model.write(System.out, "RDF/XML"); Could you please help me out.. please.. Thank you, -- Vinay
