public static List<ASTNode> getChildren(@Nullable ASTNode element) {
    ArrayList<ASTNode> results = new ArrayList<>();
    if (element == null) {
      return results;
    }
    for (ASTNode child = element.getFirstChildNode(); child != null; child = child.getTreeNext()) {
      results.add(child);
    }
    return results;
  }
public static List<ASTNode> getChildren(@Nullable ASTNode element)