code: public @NotNull TypeConversion getConversionFromDbValue(@NotNull Type source, @NotNull Type target) {
          TypeConversion conversion = findConversionFromDbValue(source, target).orElse(null);
          if (conversion != null)
              return conversion;
          else
              throw new InstantiationFailureException("could not find a conversion from " + source.getTypeName() + " to " + target.getTypeName());
      }
docs: Returns conversion for converting value of source-type to target-type, or throws exception if
  there's no such conversion.