private static void extractMultilingualItems(Metadata metadata, Property property,
                                                 String pdfBoxBaseline, XMPSchema schema) {
        //if schema is null, just go with pdfBoxBaseline
        if (schema == null) {
            if (pdfBoxBaseline != null && pdfBoxBaseline.length() > 0) {
                addMetadata(metadata, property, pdfBoxBaseline);
            }
            return;
        }

        for (String lang : schema.getLanguagePropertyLanguages(property.getName())) {
            String value = schema.getLanguageProperty(property.getName(), lang);

            if (value != null && value.length() > 0) {
                //if you're going to add it below in the baseline addition, don't add it now
                if (pdfBoxBaseline != null && value.equals(pdfBoxBaseline)) {
                    continue;
                }
                addMetadata(metadata, property, value);
                if (!property.isMultiValuePermitted()) {
                    return;
                }
            }
        }

        if (pdfBoxBaseline != null && pdfBoxBaseline.length() > 0) {
            //if we've already added something above and multivalue is not permitted
            //return.
            if (!property.isMultiValuePermitted()) {
                if (metadata.get(property) != null) {
                    return;
                }
            }
            addMetadata(metadata, property, pdfBoxBaseline);
        }
    }
Try to extract all multilingual items from the XMPSchema
<p/>
This relies on the property having a valid xmp getName()
<p/>
For now, this only extracts the first language if the property does not allow multiple
values (see TIKA-1295)

@param metadata
@param property
@param pdfBoxBaseline
@param schema
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-pdf-module/src/main/java/org/apache/tika/parser/pdf/PDMetadataExtractor.java