code: public MenuItemType getMenuItemType() {
          if (knownType != KnownType.MENU_ITEM) {
              throw new IllegalArgumentException("getMenuItemType() can only be used with MENU_ITEM responses.");
          }
          final NumberField type = (NumberField)arguments.get(6);
          final MenuItemType result = MENU_ITEM_TYPE_MAP.get(type.getValue());
          if (result == null) {
              return MenuItemType.UNKNOWN;
          }
          return result;
      }
docs: Extracts the menu item type from a {@link KnownType#MENU_ITEM} response.
  
  @return the reported type of this menu item
  
  @throws IllegalArgumentException if this is not a {@link KnownType#MENU_ITEM} response.