On 14/07/16 19:04, Chris Jones wrote:
In that case, can I request a better error message? What it told me was
confusing.
Pull request welcome!
The grammar is exactly the SPARQ 1.1 spec grammar - the javacc was used
to create both the HTML for the spec and the Jena java parser.
It takes a special rule to trigger specific error messages - the grammar
must be modified; not a lot but then it diverges.
Adding it to the ARQ extended parser does not have that issue.
Andy
Chris
On 7/14/2016 10:58 AM, Joshua TAYLOR wrote:
You can't use variables in property paths, so
?p1/?p2
isn't a legal property path. You shouldn't be able to parse it as a
legal query. As an alternative (which I'm not sure will work, but it
might be worth investigating), you could use a
ParameterizedSparqlString with "?s ?p1/?p2 ?o" as content and do
substitutions on ?p1 and ?p2 in that, which would generate a legal
query. I'm not sure whether the substitution would be performed
before any parsing has to happen though (that's why I'm not *sure*
that this would work).
On Thu, Jul 14, 2016 at 12:47 PM, A. Soroka <[email protected]> wrote:
I don't quite see how this would cause the problem, but I do note
that of the three bindings in your code below, the first is _not_ to
"s" (as you say in your description), but to "o".
---
A. Soroka
The University of Virginia Library
On Jul 14, 2016, at 12:09 PM, Chris Jones <[email protected]> wrote:
I'm building a simple query of the form "?s ?p1 / ?p2 ?o" and
binding s, p1, and p2 using QuerySolutionMap. I get this error back:
Exception in thread "main"
org.apache.jena.query.QueryParseException: Encountered " "/" "/ ""
at line 1, column 26.
Here's the code that reproduces the error, using Jena 3.1.0:
package org.cjones.test;
import org.apache.jena.query.*;
import org.apache.jena.rdf.model.ResourceFactory;
import org.apache.jena.tdb.TDBFactory;
public class Test {
public static void main(String[] args) {
Dataset dataset = TDBFactory.createDataset("db");
String queryStr ="select ?o where { ?s ?p1 / ?p2 ?o }";
QuerySolutionMap bindings =new QuerySolutionMap();
bindings.add("o",
ResourceFactory.createResource("http://example.com/Alice";));
bindings.add("p1",
ResourceFactory.createResource("http://example.com/boss";));
bindings.add("p2",
ResourceFactory.createResource("http://example.com/givenName";));
dataset.begin(ReadWrite.READ);
QueryExecution qe = QueryExecutionFactory.create(queryStr,
dataset, bindings);
ResultSet rs = qe.execSelect();
// ... dataset.end();
}
}
I don't think I'm doing anything wrong, am I?
Chris
