/*
* Copyright (c) 2005-2010, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. licenses this file to you under the Apache License,
* Version 2.0 (the "License"); you may not use this file except
* in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.wso2.carbon.mashup.javascript.hostobjects.sparql;
import com.hp.hpl.jena.query.*;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.ModelFactory;
import com.hp.hpl.jena.sparql.engine.http.HttpQuery;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.util.AXIOMUtil;
import org.mozilla.javascript.*;
import org.wso2.carbon.CarbonException;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.net.URL;
import com.hp.hpl.jena.sparql.engine.http.HttpContentType;
public class SparqlHostObject extends ScriptableObject {
private String rdfDataSource;
private String sparqlEndPoint;
private String spaqrlQuery;
private String resultType;
private static final String RESULT_TYPE_JSON = "JSON";
public SparqlHostObject() {
}
public static Scriptable jsConstructor(Context cx, Object[] args, Function ctorObj,
boolean inNewExpr) throws CarbonException {
SparqlHostObject sparqlObject = new SparqlHostObject();
if (args.length != 0) {
throw new CarbonException("SparqlObject constructor doesn't accept any arguments");
}
return sparqlObject;
}
public Object jsGet_sparqlEndPoint() {
return sparqlEndPoint;
}
public void jsSet_sparqlEndPoint(Object sparqlEndPoint) {
this.sparqlEndPoint = (String)sparqlEndPoint;
}
public Object jsGet_rdfDataSource() {
return rdfDataSource;
}
public void jsSet_rdfDataSource(Object rdfDataSource) {
this.rdfDataSource = (String) rdfDataSource;
}
public Object jsGet_spaqrlQuery() {
return spaqrlQuery;
}
public void jsSet_spaqrlQuery(Object spaqrlQuery) {
this.spaqrlQuery = (String) spaqrlQuery;
}
public Object jsGet_resultType() {
return resultType;
}
public void jsSet_resultType(Object resultType) {
this.resultType = (String) resultType;
}
public static Object jsFunction_getDataFromRdfSource(Context cx, Scriptable thisObj, Object[] args, Function funObj)
throws Exception {
String resultString;
SparqlHostObject sparqlObject = (SparqlHostObject) thisObj;
if (sparqlObject == null) {
throw new CarbonException("SparqlObject is null");
}
//Open a given rdf datasource from a URL
try {
Dataset dataSet = DatasetFactory.create(sparqlObject.rdfDataSource);
// Create a new query form a given user query
String queryString = sparqlObject.spaqrlQuery;
Query query = QueryFactory.create(queryString);
QueryExecution qe = QueryExecutionFactory.create(query, dataSet);
ResultSet results = qe.execSelect();
if ((sparqlObject.resultType) != null && (sparqlObject.resultType).toUpperCase().equals(sparqlObject.RESULT_TYPE_JSON)) {
// Output query results as JSON
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ResultSetFormatter.outputAsJSON(bos, results);
resultString = bos.toString();
} else {
// Output query results as XML
resultString = ResultSetFormatter.asXMLString(results);
OMElement e = AXIOMUtil.stringToOM(resultString);
return e.toString();
}
// Important - free up resources used running the query
qe.close();
return resultString;
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
public static Object jsFunction_getDataFromSparqlEndPoint(Context cx, Scriptable thisObj, Object[] args, Function funObj)
throws Exception {
String resultString;
SparqlHostObject sparqlObject = (SparqlHostObject) thisObj;
if (sparqlObject == null) {
throw new CarbonException("SparqlObject is null");
}
try {
// Create a new query form a given user query
String queryString = sparqlObject.spaqrlQuery;
Query query = QueryFactory.create(queryString);
QueryExecution qe = QueryExecutionFactory.sparqlService(sparqlObject.sparqlEndPoint, query);
ResultSet results = qe.execSelect();
if ((sparqlObject.resultType) != null && (sparqlObject.resultType).toUpperCase().equals(sparqlObject.RESULT_TYPE_JSON)) {
// Output query results as JSON
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ResultSetFormatter.outputAsJSON(bos, results);
resultString = bos.toString();
} else {
// Output query results as XML
resultString = ResultSetFormatter.asXMLString(results);
OMElement e = AXIOMUtil.stringToOM(resultString);
return e.toString();
}
// Important - free up resources used running the query
qe.close();
return resultString;
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
@Override
public String getClassName() {
return "Sparql";
}
}