Simon,
Thanks for a complete, minimal example. I get the same error.
I suspect it's not woodstox per se, but a lower level networking issue
because I can get things to work by reading the data as fast as
possible. Maybe woodstow's use of the inputstream is seeing the
connection close flag without making sure there isn't more data to read.
The code in ARQ SVN has a workaround for this - it slurps up the network
bytes as fast as possible, then passes them to woodstox; woodstox is not
then working over the network input stream but instead a
ByteArrayInputStream.
(An alternative, I tried was adding a buffering layer to the input
stream but that didn't work).
Andy
On 07/02/11 23:09, Simon Wibberley wrote:
Hi there,
I'm trying to query dbpedia for a list of company names. I'm
inconsistently getting WstxEOFException's caught by jena, which then
raises a ResultSetException. This happens after some data has been read
successfully. Following the tcp stream in wireshark shows a complete
response from the dbpedia server.
Is this a bug in woodstox? I've tried replacing the libs with wstx4 and
stax2, but same error occurred. Is there anything I'm doing wrong/badly
with jena/sparql? (I'm relatively new to this). The minimal test case
below seems to reproduce the error (output also below) reliably. I've
tried this on both windows7 and OS X 10.6 from different locations.
Could you check to see if you get the same error?
Any ideas?
Many thanks,
Simon Wibberley
import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.QueryFactory;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.RDFNode;
public class TestJena {
public static void main(String[] args) {
String queryString = "PREFIX rdf:
<http://www.w3.org/1999/02/22-rdf-syntax-ns#>"
+ "PREFIX dbpedia-owl: <http://dbpedia.org/ontology/>"
+ "SELECT ?var "
+ "WHERE { ?var rdf:type dbpedia-owl:Company . }";
Query query = QueryFactory.create(queryString);
QueryExecution qexec = QueryExecutionFactory.sparqlService(
"http://dbpedia.org/sparql";, query);
ResultSet rs = null;
rs = qexec.execSelect();
qexec.close();
while(rs.hasNext()) {
QuerySolution sqs = rs.next();
RDFNode node = sqs.get("var");
System.out.println(node);
}
}
}
com.ctc.wstx.exc.WstxEOFException: Unexpected EOF; was expecting a close
tag for element <uri>
at [row,col {unknown-source}]: [106,47]
at com.ctc.wstx.sr.StreamScanner.throwUnexpectedEOF(StreamScanner.java:686)
at
com.ctc.wstx.sr.BasicStreamReader.nextFromTree(BasicStreamReader.java:2730)
at com.ctc.wstx.sr.BasicStreamReader.next(BasicStreamReader.java:1019)
at
com.ctc.wstx.sr.BasicStreamReader.getElementText(BasicStreamReader.java:669)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.getOneSolution(XMLInputStAX.java:480)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.hasNext(XMLInputStAX.java:216)
at sw206.TestJena.main(TestJena.java:31)
Exception in thread "main"
com.hp.hpl.jena.sparql.resultset.ResultSetException: XMLStreamException:
Unexpected EOF; was expecting a close tag for element <uri>
at [row,col {unknown-source}]: [106,47]
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.staxError(XMLInputStAX.java:510)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.hasNext(XMLInputStAX.java:220)
at sw206.TestJena.main(TestJena.java:31)
Caused by: com.ctc.wstx.exc.WstxEOFException: Unexpected EOF; was
expecting a close tag for element <uri>
at [row,col {unknown-source}]: [106,47]
at com.ctc.wstx.sr.StreamScanner.throwUnexpectedEOF(StreamScanner.java:686)
at
com.ctc.wstx.sr.BasicStreamReader.nextFromTree(BasicStreamReader.java:2730)
at com.ctc.wstx.sr.BasicStreamReader.next(BasicStreamReader.java:1019)
at
com.ctc.wstx.sr.BasicStreamReader.getElementText(BasicStreamReader.java:669)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.getOneSolution(XMLInputStAX.java:480)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.hasNext(XMLInputStAX.java:216)
... 1 more
22:59:25,250 WARN XMLInputStAX$ResultSetStAX:73 - StAX error:
XMLStreamException: Unexpected EOF; was expecting a close tag for
element <uri>
at [row,col {unknown-source}]: [106,47]
com.ctc.wstx.exc.WstxEOFException: Unexpected EOF; was expecting a close
tag for element <uri>
at [row,col {unknown-source}]: [106,47]
at com.ctc.wstx.sr.StreamScanner.throwUnexpectedEOF(StreamScanner.java:686)
at
com.ctc.wstx.sr.BasicStreamReader.nextFromTree(BasicStreamReader.java:2730)
at com.ctc.wstx.sr.BasicStreamReader.next(BasicStreamReader.java:1019)
at
com.ctc.wstx.sr.BasicStreamReader.getElementText(BasicStreamReader.java:669)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.getOneSolution(XMLInputStAX.java:480)
at
com.hp.hpl.jena.sparql.resultset.XMLInputStAX$ResultSetStAX.hasNext(XMLInputStAX.java:216)
at sw206.TestJena.main(TestJena.java:31)
