docs: public PartialConverter getPartialConverter(Object object) {
          PartialConverter converter =
              (PartialConverter)iPartialConverters.select(object == null ? null : object.getClass());
          if (converter != null) {
              return converter;
          }
          throw new IllegalArgumentException("No partial converter found for type: " +
              (object == null ? "null" : object.getClass().getName()));
      }