org.nlp2rdf.formats.Conversor Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of nif Show documentation
A small library for NLP Interchange Format (NIF) — Edit
There is a newer version: 0.4.1
package org.nlp2rdf.formats;



import com.hp.hpl.jena.rdf.model.Model;

import org.apache.jena.riot.Lang;
import org.apache.jena.riot.RDFDataMgr;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.VelocityEngine;
import org.apache.velocity.context.Context;
import org.nlp2rdf.bean.NIFBean;
import org.nlp2rdf.bean.NIFJSONLDContext;
import org.nlp2rdf.bean.NIFType;
import org.nlp2rdf.exception.NIFException;
import org.nlp2rdf.json.JSONMinify;
import org.nlp2rdf.nif21.NIF21Format;


import java.io.IOException;
import java.io.StringWriter;
import java.util.Arrays;
import java.util.List;
import java.util.Set;

import static org.nlp2rdf.common.Constants.N3_FORMAT;
import static org.nlp2rdf.common.Constants.N3_TOKEN_SPLIT;
import static org.nlp2rdf.common.Constants.NEW_LINE;
import static org.nlp2rdf.validator.NIFMessagesException.NIF_BEANS_NOT_FOUND;

public class Conversor {

    /**
     * Return the content as RDF XML
     *
     * @return
     */
    protected String getRDFxml(Model model) {
        return getModelAsStringByFormat(model, Lang.RDFXML);
    }

    /**
     * Return the content as NTriples
     *
     * @return
     */
    protected String getNTriples(Model model) {
        return getModelAsStringByFormat(model, Lang.NTRIPLES);
    }

    /**
     * Return the content as Turtle
     *
     * @return
     */
    protected String getTurtle(List beans, Model model) {



        String n3 = getModelAsStringByFormat(model, Lang.NTRIPLES);

        if (n3 != null && !n3.isEmpty()) {
            StringBuilder builder = new StringBuilder();
            List n3Array = Arrays.asList(n3.split(NEW_LINE));
            n3Array.stream().forEach(triple-> {
                if (triple.contains(NIF21Format.RDF_PROPERTY_IDENTREF)) {

                    String[] tuples = triple.split(N3_TOKEN_SPLIT);

                    beans.stream().forEach(bean-> {
                        if (bean.getTaIdentRef() != null) {
                            String taIdent = String.format(N3_FORMAT, tuples[0].substring(1),
                                    NIF21Format.RDF_PROPERTY_IDENTREF, bean.getTaIdentRef());
                            builder.append(taIdent);
                            builder.append(NEW_LINE);
                        }
                    });


                } else {
                    builder.append(triple);
                    builder.append(NEW_LINE);
                }
            });

            return builder.toString();
        }

        return n3;


    }

    private String getModelAsStringByFormat(Model model, Lang lang) {
        StringWriter sw = new StringWriter();
        RDFDataMgr.write(sw, model, lang);
        String result = sw.toString();
        try {
            sw.close();
        } catch (IOException e) {
        }

        return result;
    }

    /**
     * Return the content as JSONLD
     *
     * @param beans
     * @param templatePath
     * @return
     */
    protected String getJSONLD(String contextJSON, List beans, String templatePath) {

        VelocityEngine velocityEngine = getVelocityEngine();

        Template template = velocityEngine.getTemplate(templatePath);
        Context context = new VelocityContext();

        if (beans.size() == 0) {
            throw new NIFException(NIF_BEANS_NOT_FOUND);
        }

        context.put("contextJSON", contextJSON);
        context.put("context", beans.get(0).getReferenceContext());
        context.put("beans", beans);

        String result = getStringFromVelocity(template, context);

        return JSONMinify.minify(result);
    }

    private void removeNIFContext(List beans) {
        NIFBean nifContext = beans.stream().filter(bean -> NIFType.CONTEXT.equals(bean.getNifType())).findFirst().get();
        beans.remove(nifContext);
    }

    private VelocityEngine getVelocityEngine() {
        VelocityEngine velocityEngine = new VelocityEngine();

        velocityEngine.init();

        return velocityEngine;
    }


    protected String getContextForJSONLD(Set ontologies, String templatePath, String language) {

        VelocityEngine velocityEngine = getVelocityEngine();

        Template template = velocityEngine.getTemplate(templatePath);

        Context context = new VelocityContext();

        context.put("contextBeans", new NIFJSONLDContext().convertToBeans(ontologies, language));

        String result = getStringFromVelocity(template, context);

         return JSONMinify.minify(result);
    }

    private String getStringFromVelocity(Template template, Context context) {
        StringWriter sw = new StringWriter();
        template.merge(context, sw);
        String result = sw.toString();
        try {
            sw.close();
        } catch (IOException e) {
        }
        return result;
    }
}