docs: public void freeSubComponents(Container container)
      {
          for (int i = 0; i < container.getComponentCount(); i++)
          {
              Component component = container.getComponent(i);
              if (component instanceof Freeable)
                  ((Freeable)component).free();
              else if (component instanceof Container)
                  this.freeSubComponents((Container)component);
          }
      }