RDF(S) Tools

Adrian Pop, adrpo@ida.liu.seProgramming Environments Laboratory

Linköping University

2November 03, 2003

<Outline/>

Introduction Tool categories

parsers, validators editors, query tools databases, crawlers

Editors demos RDFAuthor, IsaViz, RDFedt, InferEd

Query Tools Jena RDQL demo

Conclusions

3November 03, 2003

<Introduction/>

Resource Description Framework (RDF) standard for describing resources on the

web RDF Schema (RDFS)

RDF Vocabulary Description Language RDF(S) Tools must

read RDF data (parsers/validators) store RDF data (XML format, triples, or

relational/OO DBs) use RDF data (applications, RSS news, etc) manipulate RDF data (inference, query, etc)

4November 03, 2003

<Categories/>

Parsers (Jena, Redland, SWI-Prolog parser)

Validators (W3C RDF Validation service)

Editors (IsaViz, RDFAuthor, RDFEd, InferEd)

Query tools (Jena, etc) Databases (RSSDB, RDFLib)

5November 03, 2003

<Parsers part=“1”/>

Jena - A semantic Web Framework for Java http://jena.sourceforge.net/ A RDF API Reading and writing RDF in RDF/XML, N3

and N-Triples An OWL API In-memory and persistent storage RDQL – a query language for RDF

Later on, a RDQL demo

6November 03, 2003

<Parsers part=“2”/>

Redland RDF Application Framework http://www.redland.opensource.ac.uk/ A modular, object based library written in C Java, Perl, PHP, Python, Ruby and Tcl interfaces for

manipulating the RDF graph and parts Parsers and Serializers for reading and writing RDF Storage for graphs in memory and on disk Query APIs for the graph by Statement (triples) or

by Nodes and Arcs Statement Streams for construction, parsing,

de/serialisation of graphs Start of query language support. No memory leaks so far

7November 03, 2003

<Parsers part=“3”/>

SWI-Prolog parser (Online Demo) http://gollem.swi.psy.uva.nl/cgi-bin/pl-cvsweb/pl/packages/sg

ml/RDF/online.html?rev=1.11

RDFS explorer, RDF Semantic Extensions

http://wonkituck.wi-inf.uni-essen.de/rdfs.html

Interesting feature: provide semantics in Prolog for your

properties<rdf:Property rdf:ID="path"> <rdfs:isDefinedAs rdf:parseType="Literal"> path(S,O) :- statement(S,path,O). path(X,Z) :- statement(X,path,Y), path(Y,Z). </rdfs:isDefinedAs> </rdf:Property>

8November 03, 2003

<Validators/>

RDF Validation Service http://www.w3.org/RDF/Validator/

Validating RDF Parser http://139.91.183.30:9090/RDF/index.html

In general all the RDF parsers do some kind of validation

9November 03, 2003

<Editors part=“1” demo=“yes”/>

RDFAuthor http://rdfweb.org/people/damian/2001/10/RDFAuthor/

RDFAuthor Demo

10November 03, 2003

<Editors part=“2” demo=“yes”/>

IsaViz http://www.w3.org/2001/11/IsaViz/

IsaViz Demo

11November 03, 2003

<Editors part=“3” demo=“yes”/>

RDFedt http://www.jan-winkler.de/dev/e_rdfe.htm

RDFedt demo

12November 03, 2003

<Editors part=“4” demo=“yes”/>

InferEd http://www.intellidimension.com/pages/

site/products/infered/

InferEd Demo

13November 03, 2003

<Query demo=“yes”/>

Jena RDQL examples Queries over the foaf.rdf file Query 1, Select all

SELECT *WHERE(?x ?y ?z)

Query 1, Select persons that knows meSELECT ?person, ?knowsWHERE(?x <http://xmlns.com/foaf/0.1/knows> ?z), (?x <http://xmlns.com/foaf/0.1/name> ?person), (?z <http://xmlns.com/foaf/0.1/name> ?knows)

Go

14November 03, 2003

<Databases/>

Storage of RDF graphs Files

xml format, .n3 format, N-triples format

Databases relational databases (MySQL, PostgreSQL) Object-Oriented Databases (ZODB)

15November 03, 2003

<Conclusions/>

RDF Tools are mature enough become more complex

RDF is more widely used RSS feeds Mozilla sidebar, Bookmarks, etc RDFGateway (application + web + RDF

deductive DB)

16November 03, 2003

<End/>

Thank you!Questions?

17November 03, 2003

ResourcesOntology Storage and Queryinghttp://139.91.183.30:9090/RDF/publications/tr308.pdfRDF Schema explorer + RDF Semantic Extensionshttp://wonkituck.wi-inf.uni-essen.de/rdfs.htmlDave Beckett's Resource Description Framework (RDF) Resource Guidehttp://www.ilrt.bris.ac.uk/discovery/rdf/resources/RDFAuthor, RDFAuthor Tutorialhttp://rdfweb.org/people/damian/2001/10/RDFAuthor/http://rdfweb.org/people/damian/2001/10/RDFAuthor/Tutorial/Jena - A semantic Web Framework for Javahttp://jena.sourceforge.net/Redland RDF Application Frameworkhttp://www.redland.opensource.ac.uk/RDF Validation Servicehttp://www.w3.org/RDF/Validator/Validating Parser (VRP), RDF Schema Specific Database (RSSDB), The RDF Query

Language (RQL)http://139.91.183.30:9090/RDF/index.htmlRDFedthttp://www.jan-winkler.de/dev/e_rdfe.htm