예제 #1
0
 @Override
 default Tree<T> replace(T currentElement, T newElement) {
   if (isEmpty()) {
     return Empty.instance();
   } else {
     return Replace.apply((Node<T>) this, currentElement, newElement);
   }
 }
예제 #2
0
 // Idea:
 // Traverse (depth-first) until a match is found, then stop and rebuild relevant parts of the
 // tree.
 // If not found, return the same tree instance.
 static <T> Node<T> apply(Node<T> node, T currentElement, T newElement) {
   if (Objects.equals(node.getValue(), currentElement)) {
     return new Node<>(newElement, node.getChildren());
   } else {
     for (Node<T> child : node.getChildren()) {
       final Node<T> newChild = Replace.apply(child, currentElement, newElement);
       final boolean found = newChild != child;
       if (found) {
         final List<Node<T>> newChildren = node.getChildren().replace(child, newChild);
         return new Node<>(node.getValue(), newChildren);
       }
     }
     return node;
   }
 }