A modular R2RML suite built on Apache Jena. Featuring a complete domain API built on Jena's polymorphism system, SHACL validation, an R2RML processor with 100% standard conformance based an Jena's ARQ plus common tooling every R2RML project needs.
The following Java snippet demonstrates usage of the API:
public class R2rmlApiExample {
public static void main(String[] args) {
Model model = ModelFactory.createDefaultModel();
model.setNsPrefix("rdfs", RDFS.uri);
model.setNsPrefix("rr", RR.uri);
TriplesMap triplesMap = model.createResource().as(TriplesMap.class);
triplesMap
.setSubjectIri("urn:s")
.addNewPredicateObjectMap()
.addPredicate("urn:p")
.addNewObjectMap()
.setColumn("labels")
.setLanguage("en");
// All domain classes of the R2RML API *ARE* Jena Resources.
// Hence, any information - such as types or custom attributes - can be freely attached:
triplesMap
.addProperty(RDF.type, RR.TriplesMap)
.addProperty(RDFS.label, "My R2RML Mapping");
RDFDataMgr.write(System.out, model, RDFFormat.TURTLE_PRETTY);
}
}The output in turtle syntax is shown below. Note, that any of the many serialization formats supported by Jena could be used instead.
@prefix rr: <http://www.w3.org/ns/r2rml#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
[ a rr:TriplesMap ;
rdfs:label "My R2RML Mapping" ;
rr:predicateObjectMap [ rr:objectMap [ rr:column "labels" ;
rr:language "en"
] ;
rr:predicate <urn:p>
] ;
rr:subject <urn:s>
] .| r2rml-api | jena |
|---|---|
| 0.9.0 | 3.17.0 |
| 0.9.1 | 4.4.0 |
| 0.9.2 | 4.4.0 |
| 0.9.3 | 4.5.0 |
| 4.8.0-X | 4.8.0 |
Starting with Jena 4.8.0 we aligned the version of this project with Jena to make it easier to determine the compatibility.
For example, r2rml-jena-api version 4.8.0-2 indicates the second release developed against Jena 4.8.0.
Just include
<dependency>
<groupId>org.aksw.r2rml</groupId>
<artifactId>r2rml-jena-plugin</artifactId>
<version><!-- Check the link below --></version>
</dependency>List versions published on Maven Central
rmltk rml to sparql mapping.rml.ttl > mapping.raw.rq
rmltk optimize workload mapping.raw.rq --no-order > mapping.rq
The RDF processing toolkit (RPT) supports execution of the generated mapping. RPT uses this repository.
Using the single threaded Jena engine:
rpt integrate mapping.rq
Using RPT's parallel Spark-based executor:
rpt sansa query mapping.rq
- r2rml-resource-ontology: A copy of the R2RML ontology in turtle syntax
- r2rml-resource-w3c-testsuite: The W3C R2RML test suite resources (editor's draft)
- r2rml-resource-shacl: Shacl file for R2RML
- r2rml-common-vocab: String-based R2RML vocabulary
- r2rml-jena-vocab: Jena-based R2RML vocabulary
- r2rml-jena-api: Jena-based R2RML domain interfaces with RDF annotations
- r2rml-jena-arq: Utilities to import/export the R2RML model as jena constructs. Converts triples maps to jena triples, R2RML template strings to SPARQL expressions and computes effective triples maps from RefObjectMaps and more.
- r2rml-jena-plugin: Jena plugin; registers domain interfaces with jena; includes an annotation processor to create the implementations
- r2rml-jena-processor-jdbc: A standard conforming R2RML processor for JDBC datasources based on r2rml-jena-arq.
- r2rml-jena-testsuite-processor-core: Test harnish for r2rml-resource-w3c-testsuite.
- r2rml-jena-testsuite-processor-h2: Test harnish tied to a H2 database.
- r2rml-jena-sql-transforms: R2RML model transformations that affect the SQL query strings using the JSQL parser.
- r2rmlx-jena-api: Extensions of R2RML. Provides support for specification of prefix constraints for columns containing IRIs and support for and language tags from columns. Registers the r2rmlx extensions when added as a maven dependency.
The source code and shacl specification of this repo is published under the Apache License Version 2.0.
- The R2RML ontology is under http://creativecommons.org/licenses/by/3.0/
- The w3c test suite is under its respective license.