code: public static OptionalThing<ClassificationMeta> findMeta(Class<?> defmetaType, String classificationName) {
          assertArgumentNotNull("defmetaType", defmetaType);
          assertArgumentNotNull("classificationName", classificationName);
  
          // #hope switch to nativeFindMeta() in future (can be over DBFlute-1.1.1) by jflute
          final Object result;
          try {
              result = nativeMetaOf(defmetaType, classificationName);
          } catch (RuntimeException ignored) { // means not found, not use conrete type because might be changed later 
              return OptionalThing.empty();
          }
          if (result == null) {
              return OptionalThing.empty();
          }
          if (result instanceof OptionalThing<?>) { // handling for future
              @SuppressWarnings("unchecked")
              final OptionalThing<ClassificationMeta> cast = (OptionalThing<ClassificationMeta>) result;
              return cast;
          } else if (result instanceof Optional<?>) {
              @SuppressWarnings("unchecked")
              final Optional<ClassificationMeta> cast = (Optional<ClassificationMeta>) result;
              return OptionalThing.ofNullable(cast.orElse(null), () -> {
                  throw new IllegalStateException("Not found the classification code: " + defmetaType.getName() + "@" + classificationName);
              });
          } else {
              return OptionalThing.of((ClassificationMeta) result);
          }
      }
docs: =========