edu.isi.karma.kr2rml.writer.N3KR2RMLRDFWriter.java Source code

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/*******************************************************************************
 * Copyright 2014 University of Southern California
 * 
 * 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.
 * 
 * This code was developed by the Information Integration Group as part 
 * of the Karma project at the Information Sciences Institute of the 
 * University of Southern California.  For more information, publications, 
 * and related projects, please see: http://www.isi.edu/integration
 ******************************************************************************/
package edu.isi.karma.kr2rml.writer;

import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.commons.lang3.StringEscapeUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import edu.isi.karma.kr2rml.PredicateObjectMap;
import edu.isi.karma.kr2rml.URIFormatter;
import edu.isi.karma.kr2rml.mapping.R2RMLMappingIdentifier;

public class N3KR2RMLRDFWriter extends KR2RMLRDFWriter {

    private static final Logger LOG = LoggerFactory.getLogger(N3KR2RMLRDFWriter.class);
    protected URIFormatter uriFormatter;
    protected PrintWriter outWriter;
    protected Map<String, String> generatedTriples;
    String baseURI;

    public N3KR2RMLRDFWriter(URIFormatter uriFormatter, OutputStream outputStream) {
        this.outWriter = new PrintWriter(outputStream);
        this.uriFormatter = uriFormatter;
        generatedTriples = new ConcurrentHashMap<>();
        baseURI = null;
    }

    public N3KR2RMLRDFWriter(URIFormatter uriFormatter, PrintWriter writer) {
        this.outWriter = writer;
        this.uriFormatter = uriFormatter;
        generatedTriples = new ConcurrentHashMap<>();
    }

    private void outputTriple(String triple) {
        generatedTriples.put(triple, "");
    }

    @Override
    public void outputTripleWithURIObject(String subjUri, String predicateUri, String objectUri) {
        outputTriple(constructTripleWithURIObject(subjUri, predicateUri, objectUri));

    }

    private String constructTripleWithURIObject(String subjUri, String predicateUri, String objectUri) {
        if (subjUri.indexOf("<") != -1 && subjUri.indexOf(">") != -1) {
            String tmp = subjUri.substring(1, subjUri.length() - 1);
            subjUri = "<" + normalizeURI(tmp) + ">";
        }
        if (objectUri.indexOf("<") != -1 && objectUri.indexOf(">") != -1) {
            String tmp = objectUri.substring(1, objectUri.length() - 1);
            objectUri = "<" + normalizeURI(tmp) + ">";
        }
        return subjUri + " " + uriFormatter.getExpandedAndNormalizedUri(predicateUri) + " " + objectUri + " .";
    }

    @Override
    public void outputTripleWithLiteralObject(String subjUri, String predicateUri, String value, String literalType,
            String language) {
        outputTriple(constructTripleWithLiteralObject(subjUri, predicateUri, value, literalType, language));
    }

    private String constructTripleWithLiteralObject(String subjUri, String predicateUri, String value,
            String literalType, String language) {
        // Use Apache Commons to escape the value
        value = StringEscapeUtils.escapeJava(value);
        if (subjUri.indexOf("<") != -1 && subjUri.indexOf(">") != -1) {
            String tmp = subjUri.substring(1, subjUri.length() - 1);
            subjUri = "<" + normalizeURI(tmp) + ">";
        }
        //https://www.w3.org/TeamSubmission/turtle/ - Literals may be given either a language suffix or a datatype URI but not both
        if (language != null && !language.equals("")) {
            return subjUri + " " + uriFormatter.getExpandedAndNormalizedUri(predicateUri) + " \"" + value + "\""
                    + "@" + language + " .";
        } else if (literalType != null && !literalType.equals("")) {
            // Add the RDF literal type to the literal if present
            return subjUri + " " + uriFormatter.getExpandedAndNormalizedUri(predicateUri) + " \"" + value + "\""
                    + "^^<" + literalType + "> .";
        }
        return subjUri + " " + uriFormatter.getExpandedAndNormalizedUri(predicateUri) + " \"" + value + "\" .";
    }

    @Override
    public void outputQuadWithLiteralObject(String subjUri, String predicateUri, String value, String literalType,
            String language, String graph) {
        outputTriple(constructQuadWithLiteralObject(subjUri, predicateUri, value, literalType, language, graph));
    }

    private String constructQuadWithLiteralObject(String subjUri, String predicateUri, String value,
            String literalType, String language, String graph) {
        String triple = constructTripleWithLiteralObject(subjUri, predicateUri, value, literalType, language);
        if (triple.length() > 2)
            return triple.substring(0, triple.length() - 1) + "<" + graph + "> .";
        else
            return "";
    }

    @Override
    public void outputTripleWithURIObject(PredicateObjectMap predicateObjectMap, String subjUri,
            String predicateUri, String objectUri) {
        outputTripleWithURIObject(subjUri, predicateUri, objectUri);
    }

    @Override
    public void outputTripleWithLiteralObject(PredicateObjectMap predicateObjectMap, String subjUri,
            String predicateUri, String value, String literalType, String language) {
        outputTripleWithLiteralObject(subjUri, predicateUri, value, literalType, language);
    }

    @Override
    public void outputQuadWithLiteralObject(PredicateObjectMap predicateObjectMap, String subjUri,
            String predicateUri, String value, String literalType, String language, String graph) {
        outputQuadWithLiteralObject(subjUri, predicateUri, value, literalType, language, graph);
    }

    @Override
    public void finishRow() {
        for (String value : generatedTriples.keySet()) {
            outWriter.println(value);
        }
        outWriter.println("");
        generatedTriples = new ConcurrentHashMap<>();
    }

    @Override
    public void flush() {
        LOG.debug("Flushing writer");
        for (String value : generatedTriples.keySet()) {
            outWriter.println(value);
        }
        outWriter.flush();
        LOG.debug("Flushed writer");

    }

    @Override
    public void close() {
        outWriter.close();

    }

    private String normalizeURI(String URI) {
        try {
            URI = URI.replace(" ", "");
            URI uri = new URI(URI);
            if (!uri.isAbsolute() && baseURI != null)
                return baseURI + URI;
        } catch (URISyntaxException e) {
            if (baseURI != null)
                return baseURI + URI;
            else
                return URI;
        }
        return URI;
    }

    public void setBaseURI(String baseURI) {
        this.baseURI = baseURI;
    }

    @Override
    public void setR2RMLMappingIdentifier(R2RMLMappingIdentifier mappingIdentifer) {

    }

}