Hi,
can you clarify what doesn't work?
I tried your example and it would work, but I'm getting a parse
exception because DBpedia (resp. Virtuoso) still returns illegal data:
Graph g = RDFDataMgr.loadGraph("http://dbpedia.org/resource/Rome";);
System.out.println(g.size());
[line: 1863, col: 13] Failed to find a prefix name or keyword:
–(8211;0x2013)
Exception in thread "main" org.apache.jena.riot.RiotException: [line:
1863, col: 13] Failed to find a prefix name or keyword: –(8211;0x2013)
at
org.apache.jena.riot.system.ErrorHandlerFactory$ErrorHandlerStd.fatal(ErrorHandlerFactory.java:136)
at
org.apache.jena.riot.lang.LangEngine.raiseException(LangEngine.java:165)
at org.apache.jena.riot.lang.LangEngine.nextToken(LangEngine.java:108)
at
org.apache.jena.riot.lang.LangTurtleBase.triples(LangTurtleBase.java:248)
at
org.apache.jena.riot.lang.LangTurtleBase.triplesSameSubject(LangTurtleBase.java:190)
at
org.apache.jena.riot.lang.LangTurtle.oneTopLevelElement(LangTurtle.java:46)
at
org.apache.jena.riot.lang.LangTurtleBase.runParser(LangTurtleBase.java:89)
at org.apache.jena.riot.lang.LangBase.parse(LangBase.java:42)
at
org.apache.jena.riot.RDFParserRegistry$ReaderRIOTLang.read(RDFParserRegistry.java:179)
at org.apache.jena.riot.RDFDataMgr.process(RDFDataMgr.java:861)
at org.apache.jena.riot.RDFDataMgr.parse(RDFDataMgr.java:667)
at org.apache.jena.riot.RDFDataMgr.read(RDFDataMgr.java:212)
at org.apache.jena.riot.RDFDataMgr.read(RDFDataMgr.java:105)
at org.apache.jena.riot.RDFDataMgr.loadGraph(RDFDataMgr.java:346)
If there is no parsing error (e.g.http://dbpedia.org/resource/Mars works
for me) the result is as expected:
Graph g = RDFDataMgr.loadGraph("http://dbpedia.org/resource/Mars";);
System.out.println(g.size());
Output: 347
The issue was already reported by me, see [1], and [2]
[1] https://github.com/openlink/virtuoso-opensource/issues/567
[2] https://github.com/openlink/virtuoso-opensource/issues/569
Kind regards,
Lorenz
> Reading a dbPedia resource with e.g. RDFDataMgr.loadGraph() does not
> currently work (it used to work with Jena 3.1.1 ).
> Apparently this is because of the 303 redirection.
> Is there another call in Jena API to handle redirections and accepting RDF
> MIME types ?
>
> wget --save-headers --header='Accept: application/rdf+xml'
> http://dbpedia.org/resource/Rome
> --2017-01-19 09:30:08-- http://dbpedia.org/resource/Rome
> Résolution de dbpedia.org (dbpedia.org)… 194.109.129.58
> Connexion à dbpedia.org (dbpedia.org)|194.109.129.58|:80… connecté.
> requête HTTP transmise, en attente de la réponse… *303 See Other*
> Emplacement : http://dbpedia.org/data/Rome.xml [suivant]
> --2017-01-19 09:30:08-- http://dbpedia.org/data/Rome.xml
> Réutilisation de la connexion existante à dbpedia.org:80.
> requête HTTP transmise, en attente de la réponse… 200 OK
> Taille : 1003627 (980K) [application/rdf+xml]
> Enregistre : «Rome.2»
>
> less Rome.2
> HTTP/1.1 200 OK
> Date: Thu, 19 Jan 2017 08:30:08 GMT
> Content-Type: application/rdf+xml; charset=UTF-8
> Content-Length: 1003627
> Connection: keep-alive
> Vary: Accept-Encoding
> Server: Virtuoso/07.20.3217 (Linux) i686-generic-linux-glibc212-64 VDB
> Expires: Thu, 26 Jan 2017 08:30:08 GMT
> Link: <http://creativecommons.org/licenses/by-sa/3.0/>;rel="license",<
> http://dbpedia.org/data/Rome.n3>; rel="alternate"; type="text/n3";
> title="Structured Descriptor Document (N3/Turtle format)", <
> http://dbpedia.org/data/Rome.json>; rel="alternate";
> type="application/json"; title="Structured Descriptor Document (RDF/JSON
> format)", <http://dbpedia.org/data/Rome.atom>; rel="alternate";
> type="application/atom+xml"; title="OData (Atom+Feed format)", <
> http://dbpedia.org/data/Rome.jsod>; rel="alternate";
> type="application/odata+json"; title="OData (JSON format)", <
> http://dbpedia.org/page/Rome>; rel="alternate"; type="text/html";
> title="XHTML+RDFa", <http://dbpedia.org/resource/Rome>; rel="
> http://xmlns.com/foaf/0.1/primaryTopic";, <http://dbpedia.org/resource/Rome>;
> rev="describedby", <
> http://mementoarchive.lanl.gov/dbpedia/timegate/http://dbpedia.org/data/Rome.xml>;
> rel="timegate"
> X-SPARQL-default-graph: http://dbpedia.org
> Cache-Control: max-age=604800
> Access-Control-Allow-Origin: *
> Access-Control-Allow-Credentials: true
> Access-Control-Allow-Methods: GET, POST, OPTIONS
> Access-Control-Allow-Headers:
> DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding
> Accept-Ranges: bytes
>
> <?xml version="1.0" encoding="utf-8" ?>
> <rdf:RDF
> xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#";
> ...
>
--
Lorenz Bühmann
AKSW group, University of Leipzig
Group: http://aksw.org - semantic web research center
