private String prefixCode;
public ItemRefId(String refId) throws InvalidRefIdException {
int pos = refId.indexOf('-');
if (pos == -1) {
throw new InvalidRefIdException("invalid ref id");
}
try {
sequenceNum = Long.parseLong(refId.substring(pos + 1));
} catch (NumberFormatException e) {
throw new InvalidRefIdException("invalid ref id");
}
prefixCode = refId.substring(0, pos).toUpperCase();
}