final int width = reader.getWidth(0);
                final int height = reader.getHeight(0);
                if (width <= 0 || height <= 0) {
                    return Result.NO_IMAGE;
                }
                if (!fessConfig.validateThumbnailSize(width, height)) {
                    return Result.INVALID_SIZE;
                }

      this.height = 1 + Math.max(height(left), height(right));
    }

    private void recompute() {
      recomputeMultiset();
      recomputeHeight();
    }

    private AvlNode<E> rebalance() {
      switch (balanceFactor()) {
        case -2:
          // requireNonNull is safe because right must exist in order to get a negative factor.
          requireNonNull(right);
          if (right.balanceFactor() > 0) {

        data = "<img src=\"http://example/foo.jpg\" width=\"x\" height=\"x\">";
        assertNull(transformer.getThumbnailUrl(responseData, getDocument(data)));

        data = "<img src=\"http://example/foo.jpg\" width=\"10\" height=\"100\">";
        assertNull(transformer.getThumbnailUrl(responseData, getDocument(data)));

        data = "<img src=\"http://example/foo.jpg\" width=\"100\" height=\"10\">";

                final Integer height = getAttributeAsInteger(attributes, "height");
                final Integer width = getAttributeAsInteger(attributes, "width");
                if (!fessConfig.isThumbnailHtmlImageUrl(thumbnailUrl)) {
                    continue;
                }
                if (height != null && width != null) {
                    try {

    }

    private void assertImageSize(File file, int width, int height) throws IOException {
        BufferedImage img = ImageIO.read(file);
        logger.debug("width: {}, height: {}", img.getWidth(), img.getHeight());
        assertEquals("Image Width", width, img.getWidth());
        assertEquals("Image Height", height, img.getHeight());
    }

    java.math.BigDecimal getThumbnailHtmlImageMaxAspectRatioAsDecimal();

    default boolean validateThumbnailSize(final int width, final int height) {
        if (width <= 0 || height <= 0 || width < getThumbnailHtmlImageMinWidthAsInteger().intValue()
                || height < getThumbnailHtmlImageMinHeightAsInteger().intValue()) {
            return false;
        }

        out.println("<p><table border='0' cellspacing='0' cellpadding='0'><tr><td>");

        out.print("<A style=\"width: " + maxLen);
        out.print("; height: 18;\" HREF=\"");
        out.print(path);
        out.println("\"><b>&uarr;</b></a>");
        if ( fmt.equals("detail") ) {
            out.println("<br clear='all'>");
        }

        out.println( "<p><table border='0' cellspacing='0' cellpadding='0'><tr><td>" );

        out.print( "<A style=\"width: " + maxLen );
        out.print( "; height: 18;\" HREF=\"" );
        out.print( path );
        out.println( "\"><b>&uarr;</b></a>" );
        if( fmt.equals( "detail" )) {
            out.println( "<br clear='all'>" );
        }

  /**
   * The HTTP <a
   * href="https://wicg.github.io/responsive-image-client-hints/#sec-ch-viewport-height">{@code
   * Sec-CH-Viewport-Height}</a> header field name.
   *
   * @since 32.0.0
   */
  public static final String SEC_CH_VIEWPORT_HEIGHT = "Sec-CH-Viewport-Height";
  /**
   * The HTTP <a href="https://wicg.github.io/responsive-image-client-hints/#sec-ch-dpr">{@code

    String THUMBNAIL_HTML_IMAGE_MIN_WIDTH = "thumbnail.html.image.min.width";

    /** The key of the configuration. e.g. 100 */
    String THUMBNAIL_HTML_IMAGE_MIN_HEIGHT = "thumbnail.html.image.min.height";

    /** The key of the configuration. e.g. 3.0 */
    String THUMBNAIL_HTML_IMAGE_MAX_ASPECT_RATIO = "thumbnail.html.image.max.aspect.ratio";

    /** The key of the configuration. e.g. 100 */