[英]How to get in Jena the exact range of an ObjectProperty with restrictions?
I have an owl/rdf schema with object properties with range restrictions, and I'm unable to get with the Jena API the effective range class.我有一个具有范围限制的 object 属性的 owl/rdf 模式,并且我无法使用 Jena API 获得有效范围 class。
I would like to get the classes which are defined in the ontology as the range of a property.我想将本体中定义的类作为属性的范围。 For example, with the following schema:
例如,使用以下架构:
<rdf:RDF xmlns="http://localhost/Test"
xml:base="http://localhost/TEST"
xmlns:sf="http://www.opengis.net/ont/sf#"
xmlns:owl="http://www.w3.org/2002/07/owl#"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:xml="http://www.w3.org/XML/1998/namespace"
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:owlgred="http://lumii.lv/2011/1.0/owlgred#">
<owl:Ontology rdf:about="http://localhost/TEST"/>
<owl:Class rdf:about="http://localhost/TEST#Aircraft"/>
<owl:Class rdf:about="http://localhost/TEST#Waypoint"/>
<owl:Class rdf:about="http://www.w3.org/2002/07/owl#Thing"/>
<owl:ObjectProperty rdf:about="http://localhost/TEST#hasWaypoint">
<rdfs:domain rdf:resource="http://localhost/TEST#Aircraft"/>
<rdfs:range>
<owl:Restriction>
<owl:onProperty rdf:resource="http://localhost/TEST#hasWaypoint"/>
<owl:someValuesFrom rdf:resource="http://localhost/TEST#Waypoint"/>
</owl:Restriction>
</rdfs:range>
</owl:ObjectProperty>
</rdf:RDF>
And I'm doing:我正在做:
model.read(...);
OntProperty property = model.getOntProperty("http://localhost/TEST#hasWaypoint");
ExtendedIterator properties = property.listDomain();
OntClass thisClass = (OntClass) properties.next();
String dom_localname = thisClass.getLocalName();
if (thisClass.getLocalName() == null) {
Restriction restriction = thisClass.asRestriction();
OntResource resource = restriction.getOnProperty().getDomain();
dom_localname = resource.getLocalName();
}
properties = property.listRange();
thisClass = (OntClass) properties.next();
String range_localname = thisClass.getLocalName();
if (thisClass.getLocalName() == null) {
Restriction restriction = thisClass.asRestriction();
OntResource resource = restriction.getOnProperty().getRange();
range_localname = resource.getLocalName();
}
System.out.println("Domain localName: " + dom_localname);
System.out.println("Range localName: " + range_localname);
I expected to get this result:我希望得到这个结果:
Domain localName: Aircraft
Range localName: Waypoint
But I get:但我得到:
Domain localName: Aircraft
Range localName: null
This same code works without any problem if I don't use restrictions, for example, with the following schema:如果我不使用限制,则相同的代码可以正常工作,例如,使用以下模式:
<rdf:RDF xmlns="http://localhost/Test"
xml:base="http://localhost/TEST"
xmlns:sf="http://www.opengis.net/ont/sf#"
xmlns:owl="http://www.w3.org/2002/07/owl#"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:xml="http://www.w3.org/XML/1998/namespace"
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:owlgred="http://lumii.lv/2011/1.0/owlgred#">
<owl:Ontology rdf:about="http://localhost/TEST"/>
<owl:Class rdf:about="http://localhost/TEST#Aircraft"/>
<owl:Class rdf:about="http://localhost/TEST#Waypoint"/>
<owl:Class rdf:about="http://www.w3.org/2002/07/owl#Thing"/>
<owl:ObjectProperty rdf:about="http://localhost/TEST#hasWaypoint">
<rdfs:domain rdf:resource="http://localhost/TEST#Aircraft"/>
<rdfs:range rdf:resource="http://localhost/TEST#Waypoint"/>
</owl:ObjectProperty>
</rdf:RDF>
I get the expected result:我得到了预期的结果:
Domain localName: Aircraft
Range localName: Waypoint
It looks that I am not handling correctly cases where a property use a restriction.看起来我没有正确处理属性使用限制的情况。 What Am I doing wrong?
我究竟做错了什么?
Per the useful comments above, it now works.根据上面有用的评论,它现在可以工作了。 I'm doing:
我正在做:
model.read(...);
OntProperty property = model.getOntProperty("http://localhost/TEST#hasWaypoint");
ExtendedIterator properties = property.listRange();
OntClass thisClass = (OntClass) properties.next();
String range_localname = thisClass.getLocalName();
if (range_localname == null) {
Resource resource = null;
Restriction restriction = thisClass.asRestriction();
if (restriction.isAllValuesFromRestriction()) {
AllValuesFromRestriction restriction1 = restriction.asAllValuesFromRestriction();
resource = restriction1.getAllValuesFrom();
} else if (restriction.isHasValueRestriction()) {
HasValueRestriction restriction1 = restriction.asHasValueRestriction();
resource = restriction1.getHasValue().asResource();
} else if (restriction.isSomeValuesFromRestriction()) {
SomeValuesFromRestriction restriction1 = restriction.asSomeValuesFromRestriction();
resource = restriction1.getSomeValuesFrom();
} else if (restriction.isMaxCardinalityRestriction()) {
MaxCardinalityRestriction restriction1 = restriction.asMaxCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
} else if (restriction.isMinCardinalityRestriction()) {
MinCardinalityRestriction restriction1 = restriction.asMinCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
} else if (restriction.isCardinalityRestriction()) {
CardinalityRestriction restriction1 = restriction.asCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
}
if (resource != null) {
range_localname = resource.getLocalName();
}
}
System.out.println("Range localName: " + range_localname);
I have the right result:我有正确的结果:
Range localName: Waypoint
To complete the previous answer, if the restriction is qualified, Jena does not have a direct way to get the range.完成上一个答案,如果限制条件合格,Jena 没有直接的方法来获取范围。 But you can do:
但你可以这样做:
model.read(...);
OntProperty property = model.getOntProperty("http://localhost/TEST#hasWaypoint");
ExtendedIterator properties = property.listRange();
OntClass thisClass = (OntClass) properties.next();
String range_localname = thisClass.getLocalName();
if (range_localname == null) {
Resource resource = null;
Restriction restriction = thisClass.asRestriction();
if (restriction.isAllValuesFromRestriction()) {
AllValuesFromRestriction restriction1 = restriction.asAllValuesFromRestriction();
resource = restriction1.getAllValuesFrom();
} else if (restriction.isHasValueRestriction()) {
HasValueRestriction restriction1 = restriction.asHasValueRestriction();
resource = restriction1.getHasValue().asResource();
} else if (restriction.isSomeValuesFromRestriction()) {
SomeValuesFromRestriction restriction1 = restriction.asSomeValuesFromRestriction();
resource = restriction1.getSomeValuesFrom();
} else if (restriction.isMaxCardinalityRestriction()) {
MaxCardinalityRestriction restriction1 = restriction.asMaxCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
} else if (restriction.isMinCardinalityRestriction()) {
MinCardinalityRestriction restriction1 = restriction.asMinCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
} else if (restriction.isCardinalityRestriction()) {
CardinalityRestriction restriction1 = restriction.asCardinalityRestriction();
resource = restriction1.getIsDefinedBy();
} else {
// qualified restrictions can be handled like that
RDFNode node = restriction.getPropertyValue(OWL2.onClass);
resource = node.asResource();
}
if (resource != null) {
range_localname = resource.getLocalName();
}
}
System.out.println("Range localName: " + range_localname);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.