prerna.rdf.engine.wrappers.JenaSelectCheater Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of semoss Show documentation
SEMOSS
The newest version!
/*******************************************************************************
 * 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.rdf.engine.wrappers;

import java.io.IOException;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.jena.query.QuerySolution;
import org.apache.jena.query.ResultSet;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import prerna.engine.api.IConstructStatement;
import prerna.engine.api.IConstructWrapper;

public class JenaSelectCheater extends AbstractWrapper implements IConstructWrapper {

	private static final Logger logger = LogManager.getLogger(JenaSelectCheater.class);

	transient int count = 0;
	transient String [] var = null;
	transient int triples;
	transient int tqrCount=0;
	String[] queryVar;
	transient ResultSet rs = null;

	@Override
	public IConstructStatement next() {
		if(!hasNext()) {
			throw new NoSuchElementException();
		}

		IConstructStatement thisSt = new ConstructStatement();
		logger.debug("Adding a JENA statement ");
	    QuerySolution row = rs.nextSolution();
	    thisSt.setSubject(row.get(var[0])+"");
	    thisSt.setPredicate(row.get(var[1])+"");
	    thisSt.setObject(row.get(var[2]));

	    return thisSt;
	}

	@Override
	public void execute() {
		try {
			rs = (ResultSet)engine.execQuery(query);
			getVariables();
			processSelectVar();
			count=0;
		} catch (Exception e) {
			logger.error("StackTrace: ", e);
		}
	}

	@Override
	public boolean hasNext() {
		return 	rs.hasNext();
	}

	private String [] getVariables() {
		var = new String[rs.getResultVars().size()];
		List  names = rs.getResultVars();
		for(int colIndex = 0;
				colIndex < names.size();
				var[colIndex] = names.get(colIndex), colIndex++);
		return var;
	}

	public void processSelectVar() {
		if(query.contains("DISTINCT")) {
			Pattern pattern = Pattern.compile("SELECT DISTINCT(.*?)WHERE");
		    Matcher matcher = pattern.matcher(query);
		    String varString = null;
		    while (matcher.find()) {
		    	varString = matcher.group(1);
		    }

		    if (varString != null) {
		    	varString = varString.trim();
			    queryVar = varString.split(" ");
			    int num = queryVar.length+1;
			    triples = num/3;
		    }
		} else {
			Pattern pattern = Pattern.compile("SELECT (.*?)WHERE");
		    Matcher matcher = pattern.matcher(query);
		    String varString = null;
		    while (matcher.find()) {
		        varString = matcher.group(1);
		    }

		    if (varString != null) {
			    varString = varString.trim();
			    queryVar = varString.split(" ");
			    int num = queryVar.length+1;
			    triples = num/3;
		    }
		}
	}

	@Override
	public void close() throws IOException {
		
	}
}