code: public static IBAN parse(String input) {
          if (input == null || input.length() == 0) {
              throw new IllegalArgumentException("Input is null or empty string.");
          }
          if (!isLetterOrDigit(input.charAt(0)) || !isLetterOrDigit(input.charAt(input.length() - 1))) {
              throw new IllegalArgumentException("Input begins or ends in an invalid character.");
          }
          return new IBAN(toPlain(input));
      }
docs: Parses the given string into an IBAN object and confirms the check digits.
  @param input the input, which can be either plain ("CC11ABCD123...") or formatted with (ASCII 0x20) space characters ("CC11 ABCD 123. ..").
  @return the parsed and validated IBAN object, never null.
  @throws IllegalArgumentException if the input is null, malformed or otherwise fails validation.
  @see #valueOf(String)