NormalizerBase tempText = (NormalizerBase)text.clone();
// extract the next maxLength characters in the string (we have to do this using the
// Normalizer to ensure that our offsets correspond to those the rest of the
// iterator is using) and store it in "fragment".
tempText.previous();
key.setLength(0);
int c = tempText.next();
while (maxLength > 0 && c != NormalizerBase.DONE) {
if (Character.isSupplementaryCodePoint(c)) {
key.append(Character.toChars(c));