private List<Node<V>> findAllNodes(String path, boolean exact) {
        final ImmutableList.Builder<Node<V>> accumulator = ImmutableList.builder();
        findAllNodes(root, path, 0, exact, accumulator, new IntHolder());
        return accumulator.build();
    }
Finds a {@link Node} which is mapped to the given {@code path}. It is recursively called by itself
to visit the children of the given node. Returns {@code null} if there is no {@link Node} to find.
core/src/main/java/com/linecorp/armeria/server/RoutingTrie.java