![](/img/trans.png)
[英]File/ontology (turtle, N3, JSON, RDF-XML) etc to .ttl file conversions in java
[英]RDF/XML Ontology: Convert into JSON(-LD) Tree in Java
我正在尝试处理以Protégé创建的RDF / XML格式存储的现有本体(OWL 2.0),以Java中的JSON / JSON-LD树表示形式。 目标是在单独的vue.js Web应用程序中使用此处理后的数据进行可视化。
不幸的是,我正在努力做到这一点。
这是我要处理的本体(示例本体):
<?xml version="1.0"?>
<rdf:RDF xmlns="urn:absolute:example.com/"
xml:base="urn:absolute:example.com/"
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:owl="http://www.w3.org/2002/07/owl#"
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#">
<owl:Ontology rdf:about="urn:absolute:example.com/"/>
<!--
///////////////////////////////////////////////////////////////////////////////////////
//
// Classes
//
///////////////////////////////////////////////////////////////////////////////////////
-->
<!-- urn:absolute:example.com/#CPU -->
<owl:Class rdf:about="urn:absolute:example.com/#CPU">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Hardware"/>
</owl:Class>
<!-- urn:absolute:example.com/#Enduser_Application -->
<owl:Class rdf:about="urn:absolute:example.com/#Enduser_Application">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Software"/>
</owl:Class>
<!-- urn:absolute:example.com/#GPU -->
<owl:Class rdf:about="urn:absolute:example.com/#GPU">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Hardware"/>
</owl:Class>
<!-- urn:absolute:example.com/#HDD -->
<owl:Class rdf:about="urn:absolute:example.com/#HDD">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Storage"/>
</owl:Class>
<!-- urn:absolute:example.com/#Hardware -->
<owl:Class rdf:about="urn:absolute:example.com/#Hardware"/>
<!-- urn:absolute:example.com/#Keyboard -->
<owl:Class rdf:about="urn:absolute:example.com/#Keyboard">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Peripherals"/>
</owl:Class>
<!-- urn:absolute:example.com/#Mainboard -->
<owl:Class rdf:about="urn:absolute:example.com/#Mainboard">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Hardware"/>
</owl:Class>
<!-- urn:absolute:example.com/#Monitor -->
<owl:Class rdf:about="urn:absolute:example.com/#Monitor">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Peripherals"/>
</owl:Class>
<!-- urn:absolute:example.com/#Mouse -->
<owl:Class rdf:about="urn:absolute:example.com/#Mouse">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Peripherals"/>
</owl:Class>
<!-- urn:absolute:example.com/#Operating_System -->
<owl:Class rdf:about="urn:absolute:example.com/#Operating_System">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Software"/>
</owl:Class>
<!-- urn:absolute:example.com/#Peripherals -->
<owl:Class rdf:about="urn:absolute:example.com/#Peripherals">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Hardware"/>
</owl:Class>
<!-- urn:absolute:example.com/#Printer -->
<owl:Class rdf:about="urn:absolute:example.com/#Printer">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Peripherals"/>
</owl:Class>
<!-- urn:absolute:example.com/#SSD -->
<owl:Class rdf:about="urn:absolute:example.com/#SSD">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Storage"/>
</owl:Class>
<!-- urn:absolute:example.com/#Software -->
<owl:Class rdf:about="urn:absolute:example.com/#Software"/>
<!-- urn:absolute:example.com/#Storage -->
<owl:Class rdf:about="urn:absolute:example.com/#Storage">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Hardware"/>
</owl:Class>
<!-- urn:absolute:example.com/#Video_Game -->
<owl:Class rdf:about="urn:absolute:example.com/#Video_Game">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Enduser_Application"/>
</owl:Class>
<!-- urn:absolute:example.com/#Word_Processor -->
<owl:Class rdf:about="urn:absolute:example.com/#Word_Processor">
<rdfs:subClassOf rdf:resource="urn:absolute:example.com/#Enduser_Application"/>
</owl:Class>
</rdf:RDF>
<!-- Generated by the OWL API (version 4.2.8.20170104-2310) https://github.com/owlcs/owlapi -->
这是我想将此本体转换成的结构(最好是在JSON或JSON-LD中):
Thing
|-- Hardware
|-- CPU
|-- GPU
|-- Mainboard
|-- Peripherals
|-- Keyboard
|-- Monitor
|-- Mouse
|-- Printer
|-- Storage
|-- HDD
|-- SSD
|-- Software
|-- Enduser_Application
|-- Video_Game
|-- Word_Processor
|-- Operating_System
但是,本体通过其subclassOf属性定义了类之间完全相反的关系。 因此,事情似乎变得更加困难。
我已经尝试了几种不同的方法。
使用Apache Jena
Model model = ModelFactory.createOntologyModel(); model.read(ontology, "OWL"); model.write(new BufferedWriter(f), "JSON-LD");
目前,这似乎工作“最佳”。 我最终得到一个以树表示形式包含JSON-LD数据的字符串。 但是,类关系是相反的:
例如,顶层由元素Keyboard,Monitor,Mouse,Printer等组成。 它们各自的超类作为子元素附加。
如果有一种使用Apache Jena来逆转关系的方法,那将非常酷。 我目前无法想到一种可能的方式。
使用owlapi
由于某种原因,owlapi对我完全不起作用。 它一直无法解析我的本体。
使用JSON-LD框架(使用方法1的输出)
我注意到JSON-LD具有所谓的“成帧”功能,该功能实质上允许您将数据重新适配到已定义的框架中。
我修改了JSON-LD的@reverse
关键字以及rdfs:subclassOf
希望从本质上扭转这种关系。 但是,我也无法使它正常工作,而且我对JSON-LD也不完全了解。 因此,我有些挣扎。
这已经给我带来了一些不眠之夜。 如果有人知道解决方案,或者可以给我提示如何解决此问题,我将非常高兴。
非常非常感谢。
我检查了一下,确实可以使用OWL API加载您的本体并将其保存为JsonLD格式。 不过,正如@Ignazio指出的那样,我怀疑它能否解决您的问题。 为了打印出树形结构,您需要访问一个推理器,从中可以查询包含关系。
这是一个代码示例,用于加载和保存本体并将其打印为树形结构。
private static Logger logger = LoggerFactory
.getLogger(owl.api.test.StandaloneOWLNamedIndividualRetrievalv5.AppHardwareTest.class);
// Why This Failure marker
private static final Marker WTF_MARKER = MarkerFactory.getMarker("WTF");
static OWLReasoner reasoner;
static void printChildren(NodeSet<OWLClass> owlClasses) {
for (Node<OWLClass> node : owlClasses) {
logger.trace(node.getRepresentativeElement().toString());
if (!node.getRepresentativeElement().isBottomEntity())
printChildren(reasoner.getSubClasses(node.getRepresentativeElement()));
}
}
public static void main(String[] args) {
try {
// Setup physical IRI for storing ontology
Path path = Paths.get(".").toAbsolutePath().normalize();
IRI loadDocumentIRI = IRI.create("file:" + path.toFile().getAbsolutePath() + "/hardware.owl");
IRI saveDocumentIRI = IRI.create("file:" + path.toFile().getAbsolutePath() + "/hardwareSave.txt");
// Initialize
OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
OWLOntology ontology = manager.loadOntologyFromOntologyDocument(loadDocumentIRI);
// Write to JsonLD format
OWLDocumentFormat ontologyFormat = new RDFJsonLDDocumentFormat();
manager.saveOntology(ontology, ontologyFormat, saveDocumentIRI);
// Print tree structure
OWLReasonerFactory reasonerFactory = new JFactFactory();
reasoner = reasonerFactory.createReasoner(ontology);
Node<OWLClass> top = reasoner.getTopClassNode();
logger.trace(top.getRepresentativeElement().toString());
printChildren(reasoner.getSubClasses(top.getRepresentativeElement()));
} catch (Throwable t) {
logger.error(WTF_MARKER, t.getMessage(), t);
}
}
希望对您有所帮助。 祝好运。
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.