edu.cornell.mannlib.vitro.webapp.utils.jena.ExtendedLinkedDataUtils.java Source code

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Here is the source code for edu.cornell.mannlib.vitro.webapp.utils.jena.ExtendedLinkedDataUtils.java

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/* $This file is distributed under the terms of the license in /doc/license.txt$ */

package edu.cornell.mannlib.vitro.webapp.utils.jena;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.Set;

import javax.servlet.ServletContext;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.hp.hpl.jena.ontology.OntModel;
import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.QueryFactory;
import com.hp.hpl.jena.query.Syntax;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.ModelFactory;

public class ExtendedLinkedDataUtils {

    private static final Log log = LogFactory.getLog(ExtendedLinkedDataUtils.class.getName());

    public static Model createModelFromQueries(ServletContext sc, String rootDir, OntModel sourceModel,
            String subject) {
        log.debug("Exploring queries in directory '" + rootDir + "'");

        Model model = ModelFactory.createDefaultModel();

        @SuppressWarnings("unchecked")
        Set<String> pathSet = sc.getResourcePaths(rootDir);

        if (pathSet == null) {
            log.warn(rootDir + " not found.");
            return model;
        }

        for (String path : pathSet) {
            File file = new File(sc.getRealPath(path));
            if (file.isDirectory()) {
                model.add(createModelFromQueries(sc, path, sourceModel, subject));
            } else if (file.isFile()) {
                if (!path.endsWith(".sparql")) {
                    log.warn("Ignoring file " + path + " because the file extension is not sparql.");
                    continue;
                }
                model.add(createModelFromQuery(file, sourceModel, subject));
                log.debug("model size is " + model.size() + " after query in '" + path + "'");
            } else {
                log.warn("path is neither a directory nor a file " + path);
            }
        } // end - for

        return model;
    }

    public static Model createModelFromQuery(File sparqlFile, OntModel sourceModel, String subject) {

        Model model = ModelFactory.createDefaultModel();

        BufferedReader reader = null;

        try {
            try {
                reader = new BufferedReader(new FileReader(sparqlFile));
                StringBuffer fileContents = new StringBuffer();
                String ln;

                while ((ln = reader.readLine()) != null) {
                    fileContents.append(ln).append('\n');
                }

                String query = fileContents.toString();
                String subjectString = "<" + subject + ">";
                query = query.replaceAll("PERSON_URI", subjectString);

                Query q = QueryFactory.create(query, Syntax.syntaxARQ);
                QueryExecution qe = QueryExecutionFactory.create(q, sourceModel);
                qe.execConstruct(model);
            } catch (Exception e) {
                log.error("Unable to process file " + sparqlFile.getAbsolutePath(), e);
            } finally {
                if (reader != null) {
                    reader.close();
                }
            }
        } catch (IOException ioe) {
            // this is for the reader.close above
            log.warn("Exception while trying to close file: " + sparqlFile.getAbsolutePath(), ioe);
        }

        return model;
    }
}