code: @Override
      protected ProcessorResult processAttribute(Arguments arguments,
              Element element, String attributeName) {
          if (!"a".equals(element.getNormalizedName())) {
              return ProcessorResult.OK;
          }
          final String to = extractAttribute(element, arguments, attributeName);
          final String cc = extractAttribute(element, arguments, "mail:cc");
          final String bcc = extractAttribute(element, arguments, "mail:bcc");
          final String subject =
                  extractAttribute(element, arguments, MAIL_SUBJECT);
          final String body = extractAttribute(element, arguments, MAIL_BODY);
  
          // The mailto-length should not be longer than 507 characters.
          final String mailToLink = createMailToLink(to, bcc, cc, subject, body);
          final int maxLength = Math.min(mailToLink.length(), 507);
          element.setAttribute("href", mailToLink.substring(0, maxLength));
          return ProcessorResult.OK;
      }
docs: {@inheritDoc}