hu.bme.mit.trainbenchmark.generator.rdf.RDFGenerator.java Source code

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Here is the source code for hu.bme.mit.trainbenchmark.generator.rdf.RDFGenerator.java

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/*******************************************************************************
 * Copyright (c) 2010-2015, Benedek Izso, Gabor Szarnyas, Istvan Rath and Daniel Varro
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Benedek Izso - initial API and implementation
 *   Gabor Szarnyas - initial API and implementation
 *******************************************************************************/

package hu.bme.mit.trainbenchmark.generator.rdf;

import static hu.bme.mit.trainbenchmark.rdf.RDFConstants.ID_PREFIX;
import hu.bme.mit.trainbenchmark.generator.Generator;
import hu.bme.mit.trainbenchmark.generator.rdf.config.RDFGeneratorConfig;
import hu.bme.mit.trainbenchmark.rdf.RDFHelper;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.commons.cli.ParseException;
import org.apache.commons.io.FileUtils;

public class RDFGenerator extends Generator {

    public RDFGenerator(final String args[]) throws ParseException {
        super();
        generatorConfig = rdfGeneratorConfig = new RDFGeneratorConfig(args);
    }

    @Override
    protected String syntax() {
        return "RDF";
    }

    protected RDFGeneratorConfig rdfGeneratorConfig;
    protected BufferedWriter file;

    @Override
    public void initModel() throws IOException {
        // source file (DDL operations)
        final String srcFilePath = generatorConfig.getWorkspacePath()
                + "/hu.bme.mit.trainbenchmark.rdf/src/main/resources/metamodel/header.ttl";
        final File srcFile = new File(srcFilePath);

        // destination file
        final String destFilePath = generatorConfig.getModelPathNameWithoutExtension() + ".ttl";
        final File destFile = new File(destFilePath);

        // this overwrites the destination file if it exists
        FileUtils.copyFile(srcFile, destFile);

        file = new BufferedWriter(new FileWriter(destFile, true));
    }

    @Override
    public void persistModel() throws IOException {
        file.close();
    }

    @Override
    protected Object createVertex(final int id, final String type, final Map<String, Object> attributes,
            final Map<String, Object> outgoingEdges, final Map<String, Object> incomingEdges) throws IOException {

        // vertex id and type
        final String triple = String.format(":%s%d a :%s", ID_PREFIX, id, type);
        final StringBuilder vertex = new StringBuilder(triple);

        // (id)-[]->() attributes
        for (final Entry<String, Object> attribute : attributes.entrySet()) {
            final String attributeTriple = String.format(" ;\n\t:%s %s", attribute.getKey(),
                    stringValue(attribute.getValue()));
            vertex.append(attributeTriple);
        }

        // (id)-[]->() edges
        for (final Entry<String, Object> outgoingEdge : outgoingEdges.entrySet()) {
            if (outgoingEdge.getValue() == null) {
                continue;
            }

            final String edgeTriple = String.format(" ;\n\t:%s :%s%s", outgoingEdge.getKey(), ID_PREFIX,
                    outgoingEdge.getValue());
            vertex.append(edgeTriple);
        }

        vertex.append(" .");
        write(vertex.toString());

        // ()-[]->(id) edges
        for (final Entry<String, Object> incomingEdge : incomingEdges.entrySet()) {
            createEdge(incomingEdge.getKey(), incomingEdge.getValue(), id);
        }

        return id;
    }

    @Override
    protected void createEdge(final String label, final Object from, final Object to) throws IOException {
        if (from == null || to == null) {
            return;
        }
        final String triple = String.format(":%s%s :%s :%s%s .", ID_PREFIX, from, label, ID_PREFIX, to);
        write(triple);
    }

    @Override
    protected void setAttribute(final String type, final Object node, final String key, final Object value)
            throws IOException {
        final String triple = String.format(":%s%s :%s %s", ID_PREFIX, node, key, stringValue(value));
        write(triple + ".");

    }

    private String stringValue(final Object value) {
        if (value instanceof Integer) {
            return String.format("\"%d\"^^xsd:int", value);
        }
        if (value instanceof Enum<?>) {
            final Enum<?> e = (Enum<?>) value;
            return String.format(":%s", RDFHelper.addEnumPrefix(e));
        } else {
            return value.toString();
        }
    }

    public void write(final String s) throws IOException {
        file.write(s + "\n\n");
    }

}