code: @SuppressWarnings("unchecked")
      @Override
      public <T> Optional<T> convert(String rawString, Class<T> genericType, ConversionManager conversionManager, ClassLoader classLoader) {
          T value = null;
          if (!ConfigProperty.UNCONFIGURED_VALUE.equals(rawString)) {
              value = (T) conversionManager.convert(rawString, genericType);
          }
          return Optional.ofNullable(value);
      }
docs: {@inheritDoc}