docs: @Override
      public long size() {
          try {
              val response = getSearchResultResponse();
              if (LdapUtils.containsResultEntry(response)) {
                  return response.getResult().getEntries()
                      .stream()
                      .map(this.ldapServiceMapper::mapToRegisteredService)
                      .filter(Objects::nonNull).count();
              }
          } catch (final LdapException e) {
              LOGGER.error(e.getMessage(), e);
          }
          return 0;
      }