code: @SuppressWarnings("unchecked")
      public Map<String,String> getGroup(String name) {
          Map<String,String> map = null;
          Map<String,Object> groupMap = (Map<String,Object>)get(name, PropType.group);
          if (groupMap != null) {
              map = new HashMap<>();
              parseGroupMap(groupMap, map, null);  // Parses groupMap recursively
          }
          return map;
      }
docs: Returns a flattened value map with full-path keys (including prefix).