使用flying-saucer-pdf-itext5 生成pdf时html中table的行如果太高的话会被挤到第二页展示，导致第一页中空白一大块。
解决办法：
修改org.xhtmlrenderer.render.Box 类的 forcePageBreakBefore 方法。
public int forcePageBreakBefore(LayoutContext c, IdentValue pageBreakValue, boolean pendingPageName) {PageBox page = c.getRootLayer().getFirstPage(c, this);if (page == null) {XRLog.layout(Level.WARNING, "Box has no page");return 0;} else {// 纯文本类型标签不做分页时的分割if (this instanceof LineBox) {return 0;}Element element = this.getElement();if (element != null) {if (element.getTagName().equalsIgnoreCase("p") || element.getTagName().equalsIgnoreCase("span")) {return 0;} else if (element.getTagName().equalsIgnoreCase("div")) {boolean flag = true;NodeList childNodes = element.getChildNodes();int length = childNodes.getLength();for (int i = 0; i < length; i++) {Node item = childNodes.item(i);// 如果整个元素内全是文本内容则不进行分割，有一个元素是非文本类的则进行分割if (!item.getNodeName().equalsIgnoreCase("#text") && !item.getNodeName().equalsIgnoreCase("p") && !item.getNodeName().equalsIgnoreCase("span")) {flag = false;break;}}if (flag) {return 0;}}}int pageBreakCount = 1;if (page.getTop() == getAbsY()) {pageBreakCount--;if (pendingPageName && page == c.getRootLayer().getLastPage()) {c.getRootLayer().removeLastPage();c.setPageName(c.getPendingPageName());c.getRootLayer().addPage(c);}}if ((page.isLeftPage() && pageBreakValue == IdentValue.LEFT) ||(page.isRightPage() && pageBreakValue == IdentValue.RIGHT)) {pageBreakCount++;}if (pageBreakCount == 0) {return 0;}if (pageBreakCount == 1 && pendingPageName) {c.setPageName(c.getPendingPageName());}int delta = page.getBottom() + c.getExtraSpaceTop() - getAbsY();if (page == c.getRootLayer().getLastPage()) {c.getRootLayer().addPage(c);}if (pageBreakCount == 2) {page = (PageBox) c.getRootLayer().getPages().get(page.getPageNo() + 1);delta += page.getContentHeight(c);if (pageBreakCount == 2 && pendingPageName) {c.setPageName(c.getPendingPageName());}if (page == c.getRootLayer().getLastPage()) {c.getRootLayer().addPage(c);}}setY(getY() + delta);return delta;}}
再将其子类TableRowBox 中的 forcePageBreakBefore 方法内容注释掉。
public int forcePageBreakBefore(LayoutContext c, IdentValue pageBreakValue,boolean pendingPageName) {/* int currentDelta = super.forcePageBreakBefore(c, pageBreakValue, pendingPageName);// additional calculations for collapsed borders.if (c.isPrint() && getStyle().isCollapseBorders()) {// get destination page for this rowPageBox page = c.getRootLayer().getPage(c, getAbsY() + currentDelta);if (page!=null) {// calculate max spill from the collapsed top borders of each childint spill = 0;for (Iterator i = getChildIterator(); i.hasNext(); ) {TableCellBox cell = (TableCellBox)i.next();BorderPropertySet collapsed = cell.getCollapsedPaintingBorder();if (collapsed != null) {spill = Math.max(spill, (int)collapsed.top() / 2);}}// be sure that the current start of the row is >= the start of the pageint borderTop = getAbsY() + currentDelta + (int)getMargin(c).top() - spill;int rowDelta = page.getTop() - borderTop;if (rowDelta > 0) {setY(getY() + rowDelta);currentDelta += rowDelta;}}}return currentDelta;*/return 0;}
修改后的样式
还有个小问题，就是该方法会导致文字被分割，待解决。。。
