* Write a {@link TransformedWaveletDelta} to the file at the current location.
* @return length of written data
*/
private int writeTransformedWaveletDelta(TransformedWaveletDelta delta) throws IOException {
long startingPosition = file.getFilePointer();
ProtoTransformedWaveletDelta protoDelta = ProtoDeltaStoreDataSerializer.serialize(delta);
OutputStream stream = Channels.newOutputStream(file.getChannel());
protoDelta.writeTo(stream);
return (int) (file.getFilePointer() - startingPosition);
}