code: private String formatPhoneNumber() {
  
      StringBuilder buffer = new StringBuilder();
      buffer.append(this.countryCode);
      buffer.append(' ');
      buffer.append(this.areaCode);
      buffer.append(' ');
      buffer.append(this.localNumber);
      if ((this.extension != null) && (this.extension.length() > 0)) {
        buffer.append('-');
        buffer.append(this.extension);
      }
      return buffer.toString();
    }
docs: This method formats the phone number as string {@link #getValue() value}.
  
  @return the formatted phone number.