@Override
    protected int serializeItemsToByteList(List<Byte> byteList) throws TikaException, IOException {
        if (this.objectGroupMetadataList != null) {
            for (ObjectGroupMetadata objectGroupMetadata : this.objectGroupMetadataList) {
                byteList.addAll(objectGroupMetadata.serializeToByteList());
            }
        }

        return 0;
    }
Used to convert the element into a byte List

@param byteList A Byte list
@return A constant value 0
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-microsoft-module/src/main/java/org/apache/tika/parser/microsoft/onenote/fsshttpb/streamobj/ObjectGroupMetadataDeclarations.java