code: public List<Classification> list(String classificationName) {
          assertArgumentNotNull("classificationName", classificationName);
          final String delimiter = GROUP_DELIMITER;
          final String pureName;
          final String groupName;
          if (classificationName.contains(delimiter)) { // e.g. sea.land or maihamadb-sea.land
              pureName = Srl.substringFirstFront(classificationName, delimiter); // e.g. sea or maihamadb-sea
              groupName = Srl.substringFirstRear(classificationName, delimiter); // e.g. land
          } else { // e.g. sea or maihamadb-sea
              pureName = classificationName;
              groupName = null;
          }
          final ClassificationMeta meta = findClassificationMeta(pureName, () -> {
              return "list('" + classificationName + "')";
          });
          if (groupName != null) {
              final List<Classification> groupOfList = meta.groupOf(groupName);
              if (groupOfList.isEmpty()) { // means not found
                  throw new TemplateProcessingException("Not found the classification group: " + groupName + " of " + pureName);
              }
              return groupOfList;
          } else {
              return meta.listAll();
          }
      }
docs: Get list of specified classification.
  @param classificationName The name of classification, can contain group name by delimiter. (NotNull)
  @return The list of all classification. (NotNull)