Discussion :

[AbdelhediManel]

Salut,
je veux ajouter une fonction extension filter dans le grammaire sparql ,

code de fonction:

Code :

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package project;
 
import com.hp.hpl.jena.datatypes.xsd.XSDDatatype;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.ModelFactory;
import com.hp.hpl.jena.rdf.model.StmtIterator;
import com.hp.hpl.jena.sparql.expr.NodeValue;
import com.hp.hpl.jena.sparql.expr.nodevalue.XSDFuncOp;
import com.hp.hpl.jena.sparql.function.FunctionBase0;
import com.hp.hpl.jena.sparql.function.FunctionBase2;
import com.hp.hpl.jena.sparql.function.FunctionFactory;
import com.hp.hpl.jena.vocabulary.RDFS;
import com.hp.hpl.jena.rdf.model.*;
import com.hp.hpl.jena.util.FileManager;
import com.hp.hpl.jena.vocabulary.*;
 
import java.io.*;
import java.util.HashMap;
public abstract class haschild extends FunctionBase2 implements FunctionFactory{
	public NodeValue exec(NodeValue per,String ch) throws FileNotFoundException{
	Model model = ModelFactory.createDefaultModel();
	InputStream is = new BufferedInputStream(
	           new FileInputStream(
	           "c:/Users/toshibasat/Downloads/SNjournal.webscience.org-vivo.rdf"));
	 model.read(new InputStreamReader(is), "");
 
 
	 StmtIterator it=model.listStatements();
	               while (it.hasNext()){
	            Statement p=it.next();
 
	            Property prop = p.getPredicate(  );
	             Resource res2 = p.getSubject(  );
 
	                // Get object 
	                RDFNode node =p.getObject(  );
	                if((per==res2)||(node.toString()==ch)||(prop.toString()=="HasChild")) 
	                return NodeValue.makeNode("true", XSDDatatype.XSDboolean);
 
 
}
	               return NodeValue.makeNode("false", XSDDatatype.XSDboolean);}
	}

code de l'enregistrement de la fonction:

Code :

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FunctionRegistry.get().put("http://jena.hpl.hp.com/ARQ/function#haschild",haschild.class);

j'ai écrire cette requête :

Code :

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PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX f: <java:app.myFunctions.>
SELECT * WHERE {?Person foaf:name ?x. FILTER f:haschild(?Person, "Librarian").}

mais il ne fonctionne pas il affiche ce message d'erreur:

WARN [AWT-EventQueue-0] (Log.java:63) - Class not found: app.myFunctions.haschild
WARN [AWT-EventQueue-0] (E_Function.java:77) - URI <java:app.myFunctions.haschild> has no registered function factory

Question: Quelle est le problème?

[Sapience]

Code :

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Class not found: app.myFunctions.haschild

Visiblement la classe est attendue dans le package app.myFunctions.

Code :

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package project;

Mais apparemment ta classe est déclarée dans le package "project". Donc soit tu ajustes le package de ta fonction, soit tu modifies le PREFIX de la requête SPARQL.

[AbdelhediManel]

Salut,
oui c'est vrai , j'ai modifiée le prefix "PREFIX f: <java:project.>" mais il ne marche pas:
l'erreur qui afficher:

Exception in thread "AWT-EventQueue-0" com.hp.hpl.jena.query.QueryBuildException: Can't instantiate function for java:project.haschild
at com.hp.hpl.jena.sparql.function.FunctionFactoryAuto.create(FunctionFactoryAuto.java:29)
at com.hp.hpl.jena.sparql.expr.E_Function.bindFunction(E_Function.java:94)
at com.hp.hpl.jena.sparql.expr.E_Function.buildFunction(E_Function.java:73)
at com.hp.hpl.jena.sparql.expr.ExprBuild.visit(ExprBuild.java:29)
at com.hp.hpl.jena.sparql.expr.ExprFunctionN.visit(ExprFunctionN.java:109)
at com.hp.hpl.jena.sparql.expr.ExprWalker$Walker.visitExprFunction(ExprWalker.java:55)
at com.hp.hpl.jena.sparql.expr.ExprVisitorFunction.visit(ExprVisitorFunction.java:15)
at com.hp.hpl.jena.sparql.expr.ExprFunctionN.visit(ExprFunctionN.java:109)
at com.hp.hpl.jena.sparql.expr.ExprWalker.walk(ExprWalker.java:22)
at com.hp.hpl.jena.sparql.expr.ExprList.prepareExprs(ExprList.java:86)
at com.hp.hpl.jena.sparql.algebra.optimize.OpVisitorExprPrepare.visit(OpVisitorExprPrepare.java:24)
at com.hp.hpl.jena.sparql.algebra.op.OpFilter.visit(OpFilter.java:96)
at com.hp.hpl.jena.sparql.algebra.OpWalker$WalkerVisitor.visit1(OpWalker.java:85)
at com.hp.hpl.jena.sparql.algebra.OpVisitorByType.visit(OpVisitorByType.java:71)
at com.hp.hpl.jena.sparql.algebra.op.OpFilter.visit(OpFilter.java:96)
at com.hp.hpl.jena.sparql.algebra.OpWalker.walk(OpWalker.java:35)
at com.hp.hpl.jena.sparql.algebra.OpWalker.walk(OpWalker.java:25)
at com.hp.hpl.jena.sparql.algebra.optimize.Optimize.rewrite(Optimize.java:138)
at com.hp.hpl.jena.sparql.algebra.optimize.Optimize.optimize(Optimize.java:67)
at com.hp.hpl.jena.sparql.algebra.Algebra.optimize(Algebra.java:53)
at com.hp.hpl.jena.sparql.engine.main.QueryEngineMain.modifyOp(QueryEngineMain.java:72)
at com.hp.hpl.jena.sparql.engine.QueryEngineBase.createPlan(QueryEngineBase.java:104)
at com.hp.hpl.jena.sparql.engine.QueryEngineBase.getPlan(QueryEngineBase.java:97)
at com.hp.hpl.jena.sparql.engine.main.QueryEngineMain$1.create(QueryEngineMain.java:91)
at com.hp.hpl.jena.sparql.engine.QueryExecutionBase.getPlan(QueryExecutionBase.java:426)
at com.hp.hpl.jena.sparql.engine.QueryExecutionBase.startQueryIterator(QueryExecutionBase.java:400)
at com.hp.hpl.jena.sparql.engine.QueryExecutionBase.execResultSet(QueryExecutionBase.java:408)
at com.hp.hpl.jena.sparql.engine.QueryExecutionBase.execSelect(QueryExecutionBase.java:135)
at project.frame$2.actionPerformed(frame.java:138)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.lang.InstantiationException
at sun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at com.hp.hpl.jena.sparql.function.FunctionFactoryAuto.create(FunctionFactoryAuto.java:26)
... 65 more

[Sapience]

Ta classe est déclarée "abstract" et ne peut pas être instanciée. D'où l'exception.

[AbdelhediManel]

j'ai un autre problème
ma requête :

Code sql :

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SELECT *  WHERE {?Person foaf:name ?x. FILTER(f:haschild(?Person, "Librarian")). }

Erreur:

WARN [AWT-EventQueue-0] (Log.java:73) - General exception in <java:project.haschild>(?Person, "Librarian")
com.hp.hpl.jena.sparql.ARQInternalErrorException
at com.hp.hpl.jena.sparql.expr.E_Function.eval(E_Function.java:67)
at com.hp.hpl.jena.sparql.expr.ExprFunctionN.eval(ExprFunctionN.java:103)
at com.hp.hpl.jena.sparql.expr.ExprFunctionN.eval(ExprFunctionN.java:100)
at com.hp.hpl.jena.sparql.expr.ExprNode.isSatisfied(ExprNode.java:29)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIterFilterExpr.accept(QueryIterFilterExpr.java:38)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIterProcessBinding.hasNextBinding(QueryIterProcessBinding.java:53)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:86)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:30)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:86)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:30)
at com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:86)
at com.hp.hpl.jena.sparql.engine.ResultSetStream.hasNext(ResultSetStream.java:57)
at project.frame$2.actionPerformed(frame.java:139)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)