docs: public void addIdentifiableObject(String id, T idObject) {
  
          m_cache = null;
          if (m_uniqueIds && (m_objectsById.get(id) != null)) {
              removeObject(id);
          }
          if (m_relativeOrdered) {
              float pos = 1;
              if (!m_orderedObjectList.isEmpty()) {
                  pos = m_orderedObjectList.get(m_orderedObjectList.size() - 1).getPosition() + 1;
              }
              m_orderedObjectList.add(new CmsIdObjectElement<T>(idObject, pos));
          } else {
              m_objectList.add(idObject);
          }
          if (m_uniqueIds) {
              m_objectsById.put(id, idObject);
          } else {
              List<T> prevObj = m_objectsListsById.get(id);
              if (prevObj == null) {
                  List<T> list = new ArrayList<T>();
                  list.add(idObject);
                  m_objectsListsById.put(id, list);
              } else {
                  prevObj.add(idObject);
              }
          }
  
      }