code: private String getDefaultInstanceName() {
              String name = getDefinition().getName() + " #";
              int i = 0;
              Treeview tree = node.getTreeview();
  
              while (TreeUtil.findNodeByLabel(tree, name + ++i, false) != null) {}
              return name + i;
          }
docs: Return the name to be assigned to a new instance of the child component.
  <p>
  Subclasses may override to provide an alternate instance name to be given to newly
  created elements.
  
  @return The default instance name.