示例#1
0
 @SuppressWarnings("unchecked")
 static <T, U> Tree<U> apply(
     Node<T> node, Function<? super T, ? extends Iterable<? extends U>> mapper) {
   final Tree<U> mapped = Tree.ofAll(mapper.apply(node.getValue()));
   if (mapped.isEmpty()) {
     return Tree.empty();
   } else {
     final List<Node<U>> children =
         (List<Node<U>>)
             (Object)
                 node.getChildren()
                     .map(child -> FlatMap.apply(child, mapper))
                     .filter(Tree::isDefined);
     return Tree.of(mapped.getValue(), children.prependAll(mapped.getChildren()));
   }
 }
示例#2
0
 @Override
 default <U> Tree<U> flatMap(Function<? super T, ? extends Iterable<? extends U>> mapper) {
   Objects.requireNonNull(mapper, "mapper is null");
   return isEmpty() ? Empty.instance() : FlatMap.apply((Node<T>) this, mapper);
 }