public function toOWL(Ontology $ontology)
{
$output = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
$output .= "<rdf:RDF\n";
$output .= " xmlns = \"http://dbpedia.org/ontology/\"\n";
$output .= " xml:base=\"http://dbpedia.org/ontology/\"\n";
$output .= " xmlns:owl=\"http://www.w3.org/2002/07/owl#\"\n";
$output .= " xmlns:xsd=\"http://www.w3.org/2001/XMLSchema#\"\n";
$output .= " xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"\n";
$output .= " xmlns:rdfs=\"http://www.w3.org/2000/01/rdf-schema#\">\n";
$output .= "\t<owl:Ontology rdf:about=\"\">\n";
$output .= "\t\t<owl:versionInfo xml:lang=\"en\">Version " . OWLOntologyWriter::VERSION . "</owl:versionInfo>\n";
$output .= "\t</owl:Ontology>\n\n";
foreach ($ontology->getClassIterator() as $class) {
//Only write classes from the default namespace (Don't write owl, rdf and rdfs built-in classes etc.)
if (strpos($class->getName(), ':') === false) {
$this->writeClass($class, $output);
}
}
foreach ($ontology->getPropertyIterator() as $property) {
//Only write properties from the default namespace (Don't write owl, rdf and rdfs built-in properties etc.)
if (strpos($property->getName(), ':') === false) {
$this->writeProperty($property, $output);
}
}
$output .= "</rdf:RDF>\n";
return $output;
}
public static function addProperties(Ontology $ontology)
{
$ontology->addProperty(new OntologyDataTypeProperty(self::PROPERTY, $ontology->getClass("owl:Thing"), $ontology->getDataType("xsd:string")));
}
/**
* Links all classes and properties according to the configuration.
*
* TODO: It would be cleaner to use a two-stage process: Copy the data (class and property
* names etc.) from the page nodes to intermediary data structures (probably simple maps
* or simple data objects), then build the final ontology objects from these data
* structures. No need to go through the page nodes twice, no need to modify or remove
* classes after they were added to the ontology. Would also enable checks for cyclic
* dependencies etc.
*
* @param $ontology The ontology instance
* @param $pageNode The page node of the configuration page
*/
private function linkClasses(Ontology $ontology, PageNode $pageNode)
{
$name = self::getPageName($pageNode);
foreach ($pageNode->getChildren('TemplateNode') as $node) {
//Class
$templateName = $node->getTitle()->encoded();
if ($templateName == OntologyClass::TEMPLATE_NAME) {
$ontologyClass = $ontology->getClass($name);
//Sub class
$subClassNode = $node->getProperty("rdfs:subClassOf");
if ($subClassNode) {
try {
$parentClass = $ontology->getClass($subClassNode->getText());
$ontologyClass->setSubClassOf($parentClass);
} catch (\InvalidArgumentException $e) {
$this->logger->warn("subClassOf " . $name . " (" . $subClassNode->getText() . ") not found");
}
}
//Equivalent Class
$equivalentClassNode = $node->getProperty("owl:equivalentClass");
if ($equivalentClassNode) {
try {
$equivalentClass = $ontology->getClass($equivalentClassNode->getText());
$ontologyClass . setEquivalentClass($equivalentClass);
} catch (\InvalidArgumentException $e) {
$this->logger->warn("equivalentClass " . $name . " (" . $equivalentClassNode->getText() . ") not found");
}
}
} else {
if ($templateName == OntologyObjectProperty::TEMPLATE_NAME || $templateName == OntologyDataTypeProperty::TEMPLATE_NAME) {
$ontologyProperty = $ontology->getProperty($name);
//Domain
$domainUriNode = $node->getProperty("rdfs:domain");
if ($domainUriNode) {
try {
$domainClass = $ontology->getClass($domainUriNode->getText());
} catch (\InvalidArgumentException $e) {
$this->logger->warn("Domain of " . $name . " (" . $domainUriNode->getText() . ") not found. Assuming owl:Thing");
$domainClass = $ontology->getClass("owl:Thing");
}
$ontologyProperty->setDomain($domainClass);
} else {
$ontologyProperty->setDomain($ontology->getClass("owl:Thing"));
}
//Range
$rangeUriNode = $node->getProperty("rdfs:range");
if ($rangeUriNode) {
if ($ontologyProperty instanceof OntologyObjectProperty) {
try {
$rangeClass = $ontology->getClass($rangeUriNode->getText());
} catch (\InvalidArgumentException $e) {
$this->logger->warn("Range of " . $name . " (" . $rangeUriNode->getText() . ") not found. Assuming owl:Thing");
$rangeClass = $ontology->getClass("owl:Thing");
}
$ontologyProperty->setRange($rangeClass);
} else {
try {
$dataType = $ontology->getDataType($rangeUriNode->getText());
$ontologyProperty->setRange($dataType);
} catch (\InvalidArgumentException $e) {
$this->logger->warn("Range of " . $name . " (" . $rangeUriNode->getText() . ") not found. Removing property.");
$ontology->removeProperty($ontologyProperty);
}
}
} else {
if ($ontologyProperty instanceof OntologyObjectProperty) {
$ontologyProperty->setRange($ontology->getClass("owl:Thing"));
} else {
$this->logger->warn("Range of " . $name . " not defined. Removing property.");
$ontology->removeProperty($ontologyProperty);
}
}
}
}
}
}
