private final ArrayDeque<PostOrderNode<T>> stack;

    PostOrderIterator(T root) {
      this.stack = new ArrayDeque<>();
      stack.addLast(expand(root));
    }

    @Override
    protected @Nullable T computeNext() {
      while (!stack.isEmpty()) {
        PostOrderNode<T> top = stack.getLast();
        if (top.childIterator.hasNext()) {
          T child = top.childIterator.next();

        setFuture(localDelegate);
      }
    }

    @Override
    protected @Nullable String pendingToString() {
      @RetainedLocalRef ListenableFuture<V> localDelegate = delegate;
      if (localDelegate != null) {
        return "delegate=[" + localDelegate + "]";
      }
      return null;
    }

    @Override
    protected void afterDone() {
      delegate = null;
    }
  }

  /**

            // Assert
            assertNotNull(unwrapped);
            assertTrue(unwrapped instanceof DosFileFilter);

            // Verify fields preserved (via reflection since they are protected)
            var wildcardField = DosFileFilter.class.getDeclaredField("wildcard");
            wildcardField.setAccessible(true);
            var attributesField = DosFileFilter.class.getDeclaredField("attributes");

    public XmlTransformer xmlTransformer;

    public XmlTransformer xmlNsTransformer;

    public XmlTransformer xmlMapTransformer;

    public XmlTransformer xmlEntityTransformer;

    @Override
    protected void setUp() throws Exception {
        super.setUp();

        {
            xmlTransformer = new XmlTransformer();
            xmlTransformer.setName("xmlTransformer");

        private long allRecordCount;

        TestMainSearcher(int allRecordCount) {
            this.allRecordCount = allRecordCount;
        }

        @Override
        protected SearchResult search(String query, SearchRequestParams params, OptionalThing<FessUserBean> userBean) {
            int start = params.getStartPosition();
            int size = params.getPageSize();

            "WWW-Authenticate",
            "Basic realm=\"protected area\", charset=\"UTF-8\"",
          ),
        body = "Please authenticate with UTF-8.",
      ),
    )
    server.enqueue(
      MockResponse(
        code = 401,
        headers =
          headersOf(
            "WWW-Authenticate",
            "Basic realm=\"protected area\"",
          ),

   * logging statements.
   */
  private static final class NoOpService extends AbstractService {
    @Override
    protected void doStart() {
      notifyStarted();
    }

    @Override
    protected void doStop() {
      notifyStopped();
    }
  }

  /** This is never thrown but only used for logging. */

     * Handles permission and virtual host encoding.
     *
     * @param entity the DataConfig entity to convert
     * @return the converted EditBody object
     */
    protected EditBody createEditBody(final DataConfig entity) {
        final EditBody body = new EditBody();
        copyBeanToBean(entity, body, copyOp -> {
            copyOp.excludeNull();

  }

  static class DecoupledClassLoader extends URLClassLoader {

    public DecoupledClassLoader(URL[] urls) {
      super(urls);
    }

    @Override
    protected synchronized Class<?> loadClass(String name, boolean resolve)
        throws ClassNotFoundException {
      // Force Finalizer to load from this class loader, not its parent.
      if (name.equals(Finalizer.class.getName())) {

  }

  static class DecoupledClassLoader extends URLClassLoader {

    public DecoupledClassLoader(URL[] urls) {
      super(urls);
    }

    @Override
    protected synchronized Class<?> loadClass(String name, boolean resolve)
        throws ClassNotFoundException {
      // Force Finalizer to load from this class loader, not its parent.
      if (name.equals(Finalizer.class.getName())) {