void (@NotNull PackagingElement<?> child) { myChildren.add(0, child); for (int i = 1; i < myChildren.size(); i++) { PackagingElement<?> element = myChildren.get(i); if (element.isEqualTo(child)) { if (element instanceof CompositePackagingElement<?>) { ((CompositePackagingElement<?>)child).addOrFindChildren(((CompositePackagingElement<?>)element).getChildren()); } myChildren.remove(i); break; } } }