/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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.apache.clerezza.platform.concepts.core;
import java.util.Iterator;
import org.apache.clerezza.rdf.core.Graph;
import org.apache.clerezza.rdf.core.Literal;
import org.apache.clerezza.rdf.core.MGraph;
import org.apache.clerezza.rdf.core.Triple;
import org.apache.clerezza.rdf.core.UriRef;
import org.apache.clerezza.rdf.core.access.NoSuchEntityException;
import org.apache.clerezza.rdf.core.access.TcManager;
import org.apache.clerezza.rdf.ontologies.RDF;
import org.apache.clerezza.rdf.ontologies.RDFS;
import org.apache.clerezza.rdf.ontologies.SKOS;
import org.apache.clerezza.rdf.utils.GraphNode;
/**
* This class stores description of concepts resulted from searches
* performed by {@link RemoteConceptProvider}s.
*
* @author hasan
*/
public class RemoteConceptsDescriptionManager {
private UriRef REMOTE_CONCEPTS_DESCRIPTION_MGRAPH =
new UriRef("urn:x-localinstance:/remote.concepts.description");
/**
* Stores SKOS:prefLabel and RDFS.comment of concepts available in the
* specified Graph.
*
* @param graph
* the Graph which contains concepts and their descriptions.
*/
void storeConceptsDescription(Graph graph) {
MGraph remoteConceptsDescriptionMGraph =
getRemoteConceptsDescriptionMGraph();
Iterator<Triple> concepts = graph.filter(null, RDF.type, SKOS.Concept);
while (concepts.hasNext()) {
UriRef concept = (UriRef) concepts.next().getSubject();
copyConceptDescription(new GraphNode(concept, graph),
new GraphNode(concept, remoteConceptsDescriptionMGraph));
}
}
/**
* This method creates an {@link MGraph} to store concepts' descriptions
* if this graph does not already exist.
*
* @return
* an {@link MGraph}
*/
public MGraph getRemoteConceptsDescriptionMGraph() {
MGraph remoteConceptsDescriptionMGraph = null;
TcManager tcManager = TcManager.getInstance();
try {
remoteConceptsDescriptionMGraph =
tcManager.getMGraph(REMOTE_CONCEPTS_DESCRIPTION_MGRAPH);
} catch (NoSuchEntityException nsee) {
remoteConceptsDescriptionMGraph =
tcManager.createMGraph(REMOTE_CONCEPTS_DESCRIPTION_MGRAPH);
}
return remoteConceptsDescriptionMGraph;
}
private void copyConceptDescription(GraphNode sourceGraphNode,
GraphNode destinationGraphNode) {
destinationGraphNode.deleteNodeContext();
Iterator<Literal> prefLabelStatements =
sourceGraphNode.getLiterals(SKOS.prefLabel);
if (prefLabelStatements.hasNext()) {
destinationGraphNode.addProperty(SKOS.prefLabel,
prefLabelStatements.next());
}
Iterator<Literal> commentStatements =
sourceGraphNode.getLiterals(RDFS.comment);
while (commentStatements.hasNext()) {
destinationGraphNode.addProperty(RDFS.comment,
commentStatements.next());
}
}
}