1
我使用jena 2.6.4,并且我注意到命名空间有一个奇怪的行为。我使用下面的代码:奇怪的命名空间声明
public static void main(String[] args) {
String myUri = "http://www.example.com/1.0/myUri#";
OntModel model = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM);
model.setNsPrefix("myuri", myUri);
OntClass c616 = model.createClass(myUri + "616");
OntClass c123 = model.createClass(myUri + "123");
Individual a = c616.createIndividual(myUri + "a");
a.addOntClass(c123);
model.write(System.out);
}
输出是:
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:j.0="http://www.example.com/1.0/myUri#616"
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:j.1="http://www.example.com/1.0/myUri#123"
xmlns:myuri="http://www.example.com/1.0/myUri#"
xmlns:owl="http://www.w3.org/2002/07/owl#" >
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#123">
<rdf:type rdf:resource="http://www.w3.org/2002/07/owl#Class"/>
</rdf:Description>
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#a">
<rdf:type rdf:resource="http://www.example.com/1.0/myUri#123"/>
<rdf:type rdf:resource="http://www.example.com/1.0/myUri#616"/>
</rdf:Description>
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#616">
<rdf:type rdf:resource="http://www.w3.org/2002/07/owl#Class"/>
</rdf:Description>
</rdf:RDF>
我不明白,为什么下面的命名空间声明:
xmlns:j.0="http://www.example.com/1.0/myUri#616"
xmlns:j.1="http://www.example.com/1.0/myUri#123"
奇怪的是,如果我改变序列号为TURTLE(model.write(System.out, "TURTLE");
),然后我得到如下输出:
@prefix myuri: <http://www.example.com/1.0/myUri#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
<http://www.example.com/1.0/myUri#123>
a owl:Class .
myuri:a
a <http://www.example.com/1.0/myUri#123> , <http://www.example.com/1.0/myUri#616> .
<http://www.example.com/1.0/myUri#616>
a owl:Class .
其中名称空间声明符合我的预期。
public static void main(String[] args) {
String myUri = "http://www.example.com/1.0/myUri#";
OntModel model = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM);
model.setNsPrefix("myuri", myUri);
OntClass c616 = model.createClass(myUri + "c616");
OntClass c123 = model.createClass(myUri + "c123");
Individual a = c616.createIndividual(myUri + "a");
a.addOntClass(c123);
model.write(System.out);
}
输出:
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xmlns:myuri="http://www.example.com/1.0/myUri#"
xmlns:owl="http://www.w3.org/2002/07/owl#" >
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#c123">
<rdf:type rdf:resource="http://www.w3.org/2002/07/owl#Class"/>
</rdf:Description>
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#a">
<rdf:type rdf:resource="http://www.example.com/1.0/myUri#c123"/>
<rdf:type rdf:resource="http://www.example.com/1.0/myUri#c616"/>
</rdf:Description>
<rdf:Description rdf:about="http://www.example.com/1.0/myUri#c616">
<rdf:type rdf:resource="http://www.w3.org/2002/07/owl#Class"/>
</rdf:Description>
</rdf:RDF>
和乌龟格式:
@prefix myuri: <http://www.example.com/1.0/myUri#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
myuri:c123
a owl:Class .
myuri:a
a myuri:c123 , myuri:c616 .
myuri:c616
a owl:Class .
改变OntClass
名从616
到c616
和123
到c123
的时候我也注意到我不同的行为
我做错了什么?有人能解释这种奇怪的行为吗? 谢谢!
我不知道本地名称不能以数字开头:感谢您的链接!我关心的是(i)理解为什么这些名称空间是由jena添加的(如果它们不被使用),以及(ii)它们为什么只出现在RDF/XML序列化中。无论如何,我认为我的外卖课是我不能使用以数字开头的本地名称:) – MarcoS 2012-03-19 09:11:34