private Optional<org.wikidata.wdtk.datamodel.interfaces.Statement> processGDMStatement(
final Statement statement) {
final Predicate gdmPredicate = statement.getPredicate();
final Node gdmObject = statement.getObject();
final String propertyValueDataType;
final NodeType gdmObjectType = gdmObject.getType();
propertyValueDataType = determineWikidataPropertyValueDataType(gdmPredicate, gdmObjectType);
final PropertyIdValue wikidataProperty =
processGDMPredicate(gdmPredicate, propertyValueDataType);
final Optional<Value> optionalWikidataValue = processGDMObject(gdmObject);
if (!optionalWikidataValue.isPresent()) {
return Optional.empty();
}
final Value wikidataValue = optionalWikidataValue.get();
// create property value pair
final ValueSnak snak = Datamodel.makeValueSnak(wikidataProperty, wikidataValue);
// process qualified attributes at GDM statement
final Optional<List<Snak>> wikidataQualifiers = processGDMQualifiedAttributes(statement);
final List<SnakGroup> snakGroups = new ArrayList<>();
if (wikidataQualifiers.isPresent()) {
final SnakGroup snakGroup = Datamodel.makeSnakGroup(wikidataQualifiers.get());
snakGroups.add(snakGroup);
}
final Claim claim = Datamodel.makeClaim(null, snak, snakGroups);
final List<Reference> references = new ArrayList<>();
final StatementRank rank = StatementRank.NORMAL;
// note: empty string for statement id (this should be utilised for statements that are created)
// note: Statement references cannot be null
// note: Statement rank cannot be null
return Optional.ofNullable(Datamodel.makeStatement(claim, references, rank, ""));
}
private static String printGDMStatement(final Statement statement) {
final StringBuilder sb = new StringBuilder();
final Long id = statement.getId();
sb.append("{statement: id ='");
if (id != null) {
sb.append(id);
} else {
sb.append("no statement id available");
}
sb.append("' :: ");
final String uuid = statement.getUUID();
sb.append("uuid = '");
if (uuid != null) {
sb.append(uuid);
} else {
sb.append("no uuid available");
}
sb.append("' :: ");
final String subject = printGDMNode(statement.getSubject());
sb.append("subject = '").append(subject).append("' :: ");
final String predicateURI = statement.getPredicate().getUri();
sb.append("predicate = '").append(predicateURI).append("' :: ");
final String object = printGDMNode(statement.getObject());
sb.append("object = '").append(object).append("'}");
return sb.toString();
}