docs: @Override
      protected Object getTreeStructureToSave(FacesContext facesContext)
      {
          if (log.isLoggable(Level.FINEST))
          {
              log.finest("Entering getTreeStructureToSave");
          }
          UIViewRoot viewRoot = facesContext.getViewRoot();
          if (viewRoot.isTransient())
          {
              return null;
          }
          TreeStructureManager tsm = new TreeStructureManager();
          Object retVal = tsm.buildTreeStructureToSave(viewRoot);
          if (log.isLoggable(Level.FINEST))
          {
              log.finest("Exiting getTreeStructureToSave");
          }
          return retVal;
      }