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* Copyright 2015 Defense Health Agency (DHA)
*
* If your use of this software does not include any GPLv2 components:
* Licensed 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.
* ----------------------------------------------------------------------------
* If your use of this software includes any GPLv2 components:
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*******************************************************************************/
package prerna.engine.impl.rdf;
import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Vector;
import org.apache.jena.datatypes.xsd.XSDDatatype;
import org.apache.jena.query.Query;
import org.apache.jena.query.QueryExecution;
import org.apache.jena.query.QueryExecutionFactory;
import org.apache.jena.query.QueryFactory;
import org.apache.jena.query.QuerySolution;
import org.apache.jena.query.ResultSet;
import org.apache.jena.rdf.model.Model;
import org.apache.jena.rdf.model.ModelFactory;
import org.apache.jena.rdf.model.Property;
import org.apache.jena.rdf.model.RDFNode;
import org.apache.jena.rdf.model.Resource;
import org.apache.jena.rdf.model.ResourceFactory;
import org.apache.jena.riot.Lang;
import org.apache.jena.riot.RDFDataMgr;
import org.apache.jena.update.UpdateAction;
import org.apache.jena.update.UpdateFactory;
import org.apache.jena.update.UpdateRequest;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import prerna.engine.api.IDatabaseEngine;
import prerna.engine.impl.AbstractDatabaseEngine;
import prerna.util.Constants;
import prerna.util.Utility;
/**
* References the RDF source and uses the Jena API to query a database stored in an RDF file
*/
public class RDFFileJenaEngine extends AbstractDatabaseEngine {
private static final Logger classLogger = LogManager.getLogger(RDFFileJenaEngine.class);
private Model jenaModel = null;
private String propFile = null;
private boolean connected = false;
private String fileLocation = null;
private String baseURI = null;
private String rdfFileType = null;
private Lang type = null;
/**
* Opens a database as defined by its properties file. What is included in the properties file is dependent on the type of
* engine that is being initiated. This is the function that first initializes an engine with the property file at the very
* least defining the data store.
* @param smssProp contains all information regarding the data store and how the engine should be instantiated. Dependent on
* what type of engine is being instantiated.
* @throws Exception
*/
@Override
public void open(Properties smssProp) throws Exception {
super.open(smssProp);
this.fileLocation = smssProp.getProperty(Constants.RDF_FILE_NAME);
this.baseURI = smssProp.getProperty(Constants.RDF_FILE_BASE_URI);
this.rdfFileType = smssProp.getProperty(Constants.RDF_FILE_TYPE);
this.type = determineLang(rdfFileType);
this.jenaModel = ModelFactory.createDefaultModel();
RDFDataMgr.read(this.jenaModel, this.fileLocation, this.baseURI, this.type);
this.connected = true;
}
/**
* Closes the data base associated with the engine. This will prevent further changes from being made in the data store and
* safely ends the active transactions and closes the engine.
* @throws IOException
*/
@Override
public void close() throws IOException {
super.close();
this.jenaModel.close();
classLogger.info("Closing the database to the file " + Utility.cleanLogString(propFile));
}
/**
* Runs the passed string query against the engine as a SELECT query. The query passed must be in the structure of a SELECT
* SPARQL query and the result format will depend on the engine type.
* @param query the string version of the SELECT query to be run against the engine
* @return triple query results that can be displayed as a grid */
@Override
public Object execQuery(String query) {
Query q2 = QueryFactory.create(query);
QueryExecution qexec = QueryExecutionFactory.create(q2, jenaModel) ;
if(q2.isSelectType()){
ResultSet rs = qexec.execSelect();
return rs;
}
else if(q2.isConstructType()){
Model resultModel = qexec.execConstruct() ;
classLogger.info("Executing the RDF File Graph Query " + Utility.cleanLogString(query));
return resultModel;
}
else if(q2.isAskType()){
Boolean bool = qexec.execAsk() ;
classLogger.info("Executing the RDF File ASK Query " + Utility.cleanLogString(query));
return bool;
}
else {
return null;
}
}
/**
* Runs the passed string query against the engine as an INSERT query. The query passed must be in the structure of an INSERT
* SPARQL query or an INSERT DATA SPARQL query
* and there are no returned results. The query will result in the specified triples getting added to the
* data store.
* @param query the INSERT or INSERT DATA SPARQL query to be run against the engine
*/
@Override
public void insertData(String query) {
UpdateRequest request = UpdateFactory.create();
request.add(query);
UpdateAction.execute(request, this.jenaModel);
}
@Override
public void removeData(String query) {
UpdateRequest request = UpdateFactory.create();
request.add(query);
UpdateAction.execute(request, this.jenaModel);
}
@Override
public DATABASE_TYPE getDatabaseType() {
return IDatabaseEngine.DATABASE_TYPE.JENA;
}
@Override
public boolean holdsFileLocks() {
return true;
}
/**
* Processes a SELECT query just like {@link #execSelectQuery(String)} but gets the results in the exact format that the database stores them.
* This is important for things like param values so that we can take the returned value and fill the main query without needing modification
* @param sparqlQuery the SELECT SPARQL query to be run against the engine
* @return the Vector of Strings representing the full uris of all of the query results */
public Vector
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