Java 语义网编程系列六:Jena原生推理

规则的含义:

规则是表示知识的一种方式，它通常超过了owl1的表达能力，语义web上的规则是典型的条件语句:if-then 字句。只有当特定的陈述为真，才会添加新的知识。

Jena框架自带了推理引擎和所识别的规则语言，其优点jena框架自带使用相对简单，缺点并不是w3c的推理标准。

本体建模:

import com.clarkparsia.sparqlowl.parser.antlr.SparqlOwlParser.string_return;

import com.hp.hpl.jena.ontology.OntModel;

import com.hp.hpl.jena.ontology.OntModelSpec;

import com.hp.hpl.jena.rdf.model.InfModel;

import com.hp.hpl.jena.rdf.model.Model;

import com.hp.hpl.jena.rdf.model.ModelFactory;

import com.hp.hpl.jena.reasoner.Reasoner;

import com.hp.hpl.jena.reasoner.rulesys.GenericRuleReasoner;

import com.hp.hpl.jena.reasoner.rulesys.Rule;

 

public final class JenaRule

{

JenaModel jenaModel = null ;

 

/**

 * jena原生推理机推理

 * @param ruleString

 * @param filePathString

 */

public void reasoner(String ruleString, String filePathString)

{

              jenaModel = new JenaModel();

              OntModel ontModel = jenaModel.createOntologyModel(OntModelSpec.OWL_DL_MEM,filePathString);

              Reasoner reasoner = new GenericRuleReasoner(Rule.parseRules(ruleString));

              InfModel resulInfModel = ModelFactory.createInfModel(reasoner, ontModel);

              jenaModel.outPut(resulInfModel);

}

 

/**

 * 拼接谓语

 * @param prefixString

 * @param predicateString

 * @return

 */

public String getPredicate(String prefixString,String predicateString )

{

return "<"+prefixString+predicateString+">";

}

}

 

Rule 规则:

@Test

 public void testJenaRuleReasoner()

 {

 JenaModel jenaModel = new JenaModel();

 jenaModel.outPut(jenaModel.createOntologyModel(OntModelSpec.OWL_DL_MEM,fileString));

 

 System.out.println("推理后");

 

 JenaRule jenaRule = new JenaRule();

     StringBuffer ruleStringBuffer = new StringBuffer();

     //规则一: 妈妈的男性同胞为叔叔

     ruleStringBuffer.append("[rule1:");

     ruleStringBuffer.append("(?person "+ jenaRule.getPredicate(prefixString,"hasParent")+" ?parent),");

     ruleStringBuffer.append("(?parent "+jenaRule.getPredicate(prefixString, "hasSex") +" ?sex)," );

     ruleStringBuffer.append("equal(?sex,\"女\"),");

     ruleStringBuffer.append("(?parent "+jenaRule.getPredicate(prefixString, "hasSibling") +" ?sibling)," );

     ruleStringBuffer.append("(?sibling "+jenaRule.getPredicate(prefixString, "hasSex") +" ?siblingsex)," );

     ruleStringBuffer.append("equal(?siblingsex ,\"男\")");

     ruleStringBuffer.append("->");

     ruleStringBuffer.append("(?person " + jenaRule.getPredicate(prefixString, "hasUncle")+ " ?sibling )]");

     jenaRule.reasoner(ruleStringBuffer.toString(), fileString);

 }