//SPARQLのサンプルプログラム

//出典：http://www.techscore.com/tech/Others/Jena/17.html

import com.hp.hpl.jena.query.Query;

import com.hp.hpl.jena.query.QueryExecution;

import com.hp.hpl.jena.query.QueryExecutionFactory;

import com.hp.hpl.jena.query.QueryFactory;

import com.hp.hpl.jena.query.QuerySolution;

import com.hp.hpl.jena.query.ResultSet;

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

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

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

import com.hp.hpl.jena.util.FileManager;

public class SPARQLSample {

public static void main(String[] args) {

Model model = FileManager.get().loadModel(

"file:./foaf_example.rdf");

String queryString =

"PREFIX foaf: <http://xmlns.com/foaf/0.1/> "

+ "SELECT ?name ?mbox "

+ "WHERE { ?x foaf:name ?name . "

+ "?x foaf:mbox ?mbox }";

Query query = QueryFactory.create(queryString);

QueryExecution qexec =

QueryExecutionFactory.create(query, model);

ResultSet results = qexec.execSelect();

try {

while (results.hasNext()) {

QuerySolution qs = results.nextSolution();

Literal name = (Literal) qs.get("name");

Resource mbox = (Resource) qs.get("mbox");

System.out.println(name + ":" + mbox);

}

} finally {qexec.close();}

}

}

//ファイル名をfoaf_example.rdfとし、UTF-8で保存

<?xml version="1.0"?>

<rdf:RDF

xmlns:foaf="http://xmlns.com/foaf/0.1/"

xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" >

<rdf:Description rdf:nodeID="A0">

<foaf:name>四次元太郎</foaf:name>

<foaf:mbox rdf:resource="mailto:yonta@4dd.co.jp"/>

</rdf:Description>

<rdf:Description rdf:nodeID="A1">

<foaf:name>四次元次郎</foaf:name>

<foaf:mbox rdf:resource="mailto:jiro@4dd.co.jp"/>

</rdf:Description>

</rdf:RDF>