code: private static final int parseBase64ConstantString (final String value) {
          final String s = value.substring(2);// crop "0b"/"0B" at the beginning
          final int length = s.length();
          int result = 0;
          for (int i = 0; i < length; ++i) {
              final char c = s.charAt(length - 1 - i);
              result += base64ValueOf(c) * Math.pow(64, i);
          }
          return result;
      }
docs: Parses an integer value from a {@link String} encoded in Base64 format.
  <p>
  This method does not check the passed {@link String} before parsing, so this method should only be used on string
  which are certain to match the required format.
  
  @param value a {@link String} containing (only) an integer encoded in Base64 format
  @return the parsed integer