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1、语义网开发工具：Jena1JenaJena由 HP Labs（http:/）开发的Java开发工具包 用于开发语义网的应用系统 Jena的功能解析RDF模型提供对RDFS、OWL、DAML+OIL等本体的操作支持基于本体的规则的推理和验证2JenaJena includes: A RDF API Reading and writing RDF in RDF/XML, N3 and N-Triples An OWL API In-memory and persistent storage SPARQL query engine a rule-based inference engine 3一、解
2、析RDF模型Jena定义了许多接口来访问和处理RDF陈述RDF图称为模型，用Model接口表示陈述用Statement接口表示资源用Resource接口表示属性用Property接口表示常量用Literal接口表示提供了一个RDFNode接口作为Resource、 Property、 Literal的超 接口 通过接口操作RDF创建资源、属性等RDF元素添加、删除模型中的陈述 查询RDF模型以XML/RDF、三元组格式读写RDF文档4创建简单 RDF 模型创建描述一组虚构家庭成员之间关系的模型使用来自“关系”词汇表(http:/purl.org/vocab/relationship)的属性 s
3、iblingOf 、 spouseOf 、 parentOf 和 childOf 来描述家庭成员之间关系。家庭成员用来自虚构名称空间的 URI（ http:/family/ ）进行标识51、创建模型 模型是RDF图在Jena中的表示形式模型由一组RDF陈述组成通过模型可以创建资源、属性、常量增加、删除陈述可进行查询模型创建模型ModelFactory 类用于创建不同类型的模型ModelFactory.createDefaultModel()：创建一个空的、内存模型，返回 Model 实例例： Model model = ModelFactory.createDefaultModel();62、
4、创建属性使用 Model.createProperty创建属性Property createProperty(String nameSpace, String localName) nameSpace：命名空间 localName：属性局部名称/ Namespace declarationsString familyUri = “http:/family/“;String relationshipUri = “http:/purl.org/vocab/relationship/“;/ Create the types of Property to describe relationships
5、in the modelProperty childOf = model.createProperty(relationshipUri,“childOf“);Property parentOf = model.createProperty(relationshipUri,“parentOf“);Property siblingOf = model.createProperty(relationshipUri,“siblingOf“);Property spouseOf = model.createProperty(relationshipUri,“spouseOf“);73、创建资源使用Mod
6、el. createResource创建资源Resource createResource(String uri) uri：资源的URI/ Create resources representing the people in our modelResource adam = model.createResource(familyUri+“adam“);Resource beth = model.createResource(familyUri+“beth“);Resource chuck = model.createResource(familyUri+“chuck“);Resource d
7、otty = model.createResource(familyUri+“dotty“);Resource edward = model.createResource(familyUri+“edward“);Resource fran = model.createResource(familyUri+“fran“);Resource greg = model.createResource(familyUri+“greg“);Resource harriet = model.createResource(familyUri+“harriet“);84、添加陈述使用Resource.addPr
8、operty添加关于资源的陈述到模型 Resource addProperty(Property p, RDFNode o) p:陈述的谓词，o：陈述的客体，本资源为主体/ Add properties to describing the relationships between themadam.addProperty(siblingOf,beth);adam.addProperty(spouseOf,dotty);adam.addProperty(parentOf,edward);adam.addProperty(parentOf,fran);beth.addProperty(sibli
9、ngOf,adam);beth.addProperty(spouseOf,chuck);chuck.addProperty(spouseOf,beth);dotty.addProperty(spouseOf,adam);dotty.addProperty(parentOf,edward);dotty.addProperty(parentOf,fran);94、添加陈述（续）也可使用Model. createStatement创建陈述Statement createStatement(Resource s, Property p, RDFNode o) Model add(Statement s
10、tmt) / Statements can also be directly created .Statement statement1 = model.createStatement(edward,childOf,adam);Statement statement2 = model.createStatement(edward,childOf,dotty);Statement statement3 = model.createStatement(edward,siblingOf,fran);/ . then added to the model:model.add(statement1);m
11、odel.add(statement2);model.add(statement3);104、添加陈述（续）/ Arrays of Statements can also be added to a Model:Statement statements = new Statement5;statements0 = model.createStatement(fran,childOf,adam);statements1 = model.createStatement(fran,childOf,dotty);statements2 = model.createStatement(fran,sibl
12、ingOf,edward);statements3 = model.createStatement(fran,spouseOf,greg);statements4 = model.createStatement(fran,parentOf,harriet);model.add(statements);/ A List of Statements can also be addedList list = new ArrayList();list.add(model.createStatement(greg,spouseOf,fran);list.add(model.createStatement
13、(greg,parentOf,harriet);list.add(model.createStatement(harriet,childOf,fran);list.add(model.createStatement(harriet,childOf,greg);model.add(list);115、查询RDF模型Model接口提供对模型中的资源、属性、陈述等的查询listStatements()：List all statements listStatements(Resource s, Property p, RDFNode o) : Find all the statements matc
14、hing a pattern. listSubjects(): List all resources which are subjects of statements. listSubjectsWithProperty(Property p) : List all subjects with a given property listObjects(): List all objects in a model. listObjectsOfProperty(Property p) : List all objects of a given property 125、查询RDF模型(续)列出陈述S
15、tmtIterator listStatements() 列出所有陈述结果存放在陈述迭代器中StmtIterator listStatements(Resource s, Property p, RDFNode o) 查找满足给定模式的陈述 s: 查找的资源，p: 查找的谓词，o: 查找的客体参数可为null，表示匹配任何值例如：/ Find the exact statement “adam is a spouse of dotty“ model.listStatements(adam,spouseOf,dotty); 135、查询RDF模型(续)例：/ Find any statement
16、s made about adam StmtIterator iter = model.listStatements(adam,null,(RDFNode)null);/ print out the predicate, subject and object of each statementwhile (iter.hasNext() Statement stmt = iter.nextStatement(); / get next statementResource subject = stmt.getSubject(); / get the subjectProperty predicate = stmt.getPredicate(); / get the predicateRDFNo
