SAREF Generated Library in Java with RDF4J by OLGA
RDF4 is a Java based serializer. Its API is very low level and close to the RDF language.
In the example folder, a Java based maven solution is provided which relies on RDF4J saref-0.0.1.jar which is generated by OLGA, as shown in the figure below.
The generated code of the saref-RDF4J-0.0.1.jar can be found here.
In the following a simple example is provided to depict the usage of the generated library (saref-RDF4J-0.0.1.jar) with the RDF4J library.
Saref-RDF4J-0.0.1.jar contains already the generated interfaces, classes with their annotations. Therefore, the instantiation can take place:
private static List create_SAREF_Instances()
{
String ns = "http://w3id/saref/instance/example#";
ITemperatureUnit temperatureUnit = new TemperatureUnit(ns, "degree_Celsius");
IMeasurement indoorTemperature = new Measurement(ns, "2");
indoorTemperature.addIsmeasuredin_Only((IUnitOfMeasure) temperatureUnit);
((Measurement)indoorTemperature).setHasvalue(32.5f);
((Measurement)indoorTemperature).setHastimestamp(new Date());
ITemperature temperature = new Temperature(ns, "3");
((IProperty)temperature).addRelatestomeasurement_Only((Measurement)indoorTemperature);
ITemperatureSensor temperatureSensor = new TemperatureSensor(ns, "4");
((TemperatureSensor)temperatureSensor).setHasmanufacturer_String("CompanyA");
((TemperatureSensor)temperatureSensor).setHasmodel_String("M321");
((TemperatureSensor)temperatureSensor).setHasdescription_String("Low range Zigee temperature sensor");
((IDevice)temperatureSensor).addMakesmeasurement_Only((IMeasurement)indoorTemperature);
}The output of the topology (ontology instances) can be serialized and saved in a jsonld file. The following, code snippet, serializes the content in an rdf file which can be found here.
Rio.write(GLOBAL.model, System.out, RDFFormat.TURTLE);