Hi,
Would it be possible to add a QueryExecutionFactory (QEF) *interface* to
Jena?
The com.hp.hpl.jena.query.QueryExecutionFacotry has lots of static
factory methods, but I guess it would be very useful if Jena itself
provided such an interface (either different package, different name or
both) because
then implementations based on Jena could rely on such interface (see
below and [1]) in a (quasi) standard way, and other projects could
provide fancy implementations.
public interface QueryExecutionFactory
extends QueryExecutionFactoryString, QueryExecutionFactoryQuery
{ /** * Some Id identifying the SPARQL service, such as a name given to
a jena Model or the URL of a remote service */
String getId(); /** * Some string identifying the state of this
execution factory, such as the selected graphs, or for query federation
the configured endpoints and their respective graphs. * Used for caching */
String getState();
}
The reason I ask this, is because I created [2], which uses this
architecture to transparently add delay, caching and pagination to a QEF
- i.e. you could just pose a usual SPARQL query to DBpedia, and [2] will
take care of retrieving the *complete* result, thereby caching each page
so that one can resume pagination from cache should something go wrong.
But for example, someone might provide a parallel pagination component,
or some query federation system, such as FedX could be wrapped with such
interface as well, and application developers would not have to rely on
a specific implementation.
Cheers,
Claus
[1]
https://github.com/AKSW/jena-sparql-api/blob/master/jena-sparql-api-core/src/main/java/org/aksw/jena_sparql_api/core/QueryExecutionFactory.java
[2] https://github.com/AKSW/jena-sparql-api
--
Dipl. Inf. Claus Stadler
Department of Computer Science, University of Leipzig
Research Group: http://aksw.org/
Workpage & WebID: http://aksw.org/ClausStadler
Phone: +49 341 97-32260
