// 9.update file entry encryption data.
String checksum = new Base64Binary(checksumBytes).toString();
FileEntryElement fileEntryElement = fileEntry.getOdfElement();
EncryptionDataElement encryptionDataElement = OdfElement.findFirstChildNode(EncryptionDataElement.class, fileEntryElement);
if (encryptionDataElement != null) {
fileEntryElement.removeChild(encryptionDataElement);
}
encryptionDataElement = fileEntryElement.newEncryptionDataElement(checksum, "SHA1/1K");
String initialisationVector = new Base64Binary(iv).toString();
AlgorithmElement algorithmElement = OdfElement.findFirstChildNode(AlgorithmElement.class, encryptionDataElement);
if (algorithmElement != null) {