it.uniroma2.art.sheet2rdf.pearl.GraphPearlElementTripleBased Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of sheet2rdf-core Show documentation
There is a newer version: 6.0.6
package it.uniroma2.art.sheet2rdf.pearl;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Value;
import org.eclipse.rdf4j.rio.ntriples.NTriplesUtil;

import it.uniroma2.art.coda.structures.ValueOrString;
import it.uniroma2.art.sheet2rdf.utils.S2RDFUtils;

public class GraphPearlElementTripleBased extends GraphPearlElement {
	
	private List triplesList;
	
	public GraphPearlElementTripleBased(boolean optional) {
		super(optional);
		triplesList = new ArrayList();
	}
	
	/**
	 * Adds a graph triple to the GraphPearlElement
	 * @param subject
	 * @param predicate if null, the serialization will replace the predicate with a placeholder like 
	 * <please_provide_a_predicate>
	 * @param object
	 */
	public void add(String subject, IRI predicate, ValueOrString object){
		subject = "$"+subject;
		triplesList.add(new GraphTriple(subject, predicate, object));
	}
	
	@Override
	public String serialize(String tabs, Map prefixMapping){
		String output = "";
		for (int i=0; i it has not been collapsed to qname
					predicateSerialization = NTriplesUtil.toNTriplesString(triple.getPredicate());
				} else {
					predicateSerialization = qname;
				}
			}
			String objectSerialization = "";
			ValueOrString object = triple.getObject();
			if (object == null) {
				objectSerialization = "%pls_provide_a_value%";
			} else if (object.isValue()) {
				Value objValue = object.getValue();
				if (objValue instanceof IRI) {
					//try to get the IRI as qname
					String qname = S2RDFUtils.asQName((IRI)objValue, prefixMapping);
					if (qname != null) {
						objectSerialization = qname;
					} else {
						objectSerialization = NTriplesUtil.toNTriplesString(objValue);
					}
				}
			} else {
				objectSerialization = object.getString();
			}
			if (i==0){
				if (optional) {
					output = subject + " " + predicateSerialization + " " + objectSerialization + " .";
				} else {
					output = tabs +subject + " " + predicateSerialization + " " + objectSerialization + " .";
				}
			} else {
				output = output + "\n";
				if (optional) {
					output = output + "\t";//if is the 2nd row of an optional, indent further
				}
				output = output + tabs +subject + " " + predicateSerialization + " " + objectSerialization + " .";
			}
		}
		if (optional){
			output = tabs + "OPTIONAL { " + output + " }";
		}
		return output;
	}
	
	
	private class GraphTriple{
		
		private String subject;
		private IRI predicate;
		private ValueOrString object;
		
		public GraphTriple(String subject, IRI predicate, ValueOrString object){
			this.subject = subject;
			this.predicate = predicate;
			this.object = object;
		}

		public String getSubject() {
			return subject;
		}

		public IRI getPredicate() {
			return predicate;
		}

		public ValueOrString getObject() {
			return object;
		}
	}

}