Where is the striping error?

Question

I am trying to work with the RDF dump of DBLP, available from DBLP in RDF. I attempted to use Jena's rdfcat to convert that file to into Turtle format:

rdfcat -x dblp-2006-02-06.rdf -out t > dblp.ttl

Unfortunately, this aborts with the following error message:

Exception in thread "main" org.apache.jena.riot.RiotException: [line: 378, col:
147] {E202} Expecting XML start or end element(s). String data "
????????????????????????????????????????????????????????????????????????????????
??????????????????????????????????????????????????????????????????" not allowed.
 Maybe a striping error.
        at org.apache.jena.riot.system.ErrorHandlerFactory$ErrorHandlerStd.error
(ErrorHandlerFactory.java:128)
        at org.apache.jena.riot.lang.LangRDFXML$ErrorHandlerBridge.error(LangRDF
XML.java:246)
…

As far as I could learn from another question, What is a striping error?, a striping error occurs in RDF/XML parsing when the hierarchical XML structure does not conform to RDF/XML's even/odd rule. Now, looking into that file, the respective part of the file looks like this:

<rdf:Description rdf:about="http://www.informatik.uni-trier.de/~ley/db/journals/ac/ac40.html#YousifTD95"><dc:identifier>journals/ac/YousifTD95</dc:identifier><dc:date>2002-01-03</dc:date><rdf:type rdf:resource="http://sw.deri.org/~aharth/2004/07/dblp/dblp.owl#Article"/>
<dc:creator><foaf:Person rdf:nodeID="MazinSYousif"><foaf:name>Mazin S. Yousif</foaf:name></foaf:Person></dc:creator>
<dc:creator><foaf:Person rdf:nodeID="MatthewThazhuthaveetil"><foaf:name>Matthew Thazhuthaveetil</foaf:name></foaf:Person></dc:creator>
<dc:creator><foaf:Person rdf:nodeID="ChitaRDas"><foaf:name>Chita R. Das</foaf:name></foaf:Person></dc:creator>
<dc:title rdf:parseType="Literal">Cache Coherence in Multiprocessors: A Survey.</dc:title>
<pages>127-179</pages>
<year>1995</year>
<volume>40</volume>
<journal>Advances in Computers</journal>
</rdf:Description>

Line 378 seems to be the one with Matthew Thazhuthaveetil, according to Nano. However, somehow, I fail to see where that line could be structurally problematic (in particular when comparing that line to other lines around). Is there really a structural problem there (and if so, what is it), or is the error message misleading?

Answer 1

Just tried this myself with apache jena 2.11.1 and it was fine. Have you tried `riot --validate'?

The error is curious:

Exception in thread "main" org.apache.jena.riot.RiotException: [line: 378, col:
147] {E202} Expecting XML start or end element(s). String data "
????????????????????????????????????????????????????????????????????????????????
??????????????????????????????????????????????????????????????????" not allowed.
Maybe a striping error.

It's not showing printable characters, which is mysterious.

The error simply means that the rdf contains non-whitespace characters outside a property tag. That suggests it might have invisible junk, perhaps trailing after the </dc:creator>?

I don't see anything like that, so it really feels like an IO error somewhere.