maven项目开发遇到的问题。
这个问题有点坑，测试时doc(x)、xls(x)添加水印后正常显示，而ppt(x)打开后水印看不到，但是可以被选中。不了解pdf文档，搜了半天，最后发现pdf文档是分层的（用词不准）…设置水印时必须获取pdf文档的最上层(getOverContent())才能使得你设置的水印显示出来。mark下
/*** pdf添加水印** @param filePO po* @param response res* @param waterMarkContent 水印内容* @throws DocumentException* @throws IOException*/public static void setTextWaterMarkForPdf(FilePO filePO, HttpServletResponse response, String waterMarkContent)throws DocumentException, IOException {PdfReader reader = new PdfReader(filePO.getOnlinePath());PdfStamper stamper = new PdfStamper(reader, response.getOutputStream());PdfGState gs = new PdfGState();//设置透明度gs.setFillOpacity(0.3f);BaseFont font = BaseFont.createFont("Courier", "Cp1252", false);JLabel label = new JLabel();label.setText(waterMarkContent);FontMetrics metrics = label.getFontMetrics(label.getFont());int textH = metrics.getHeight() * 2;int textW = metrics.stringWidth(label.getText()) * 2;int total = reader.getNumberOfPages() + 1;PdfContentByte content;for (int i = 1; i < total; i++) {//**注意！这里是获取pdf最顶层，否则会使得部分pdf文档无法显示水印content = stamper.getOverContent(i);content.beginText();content.setGState(gs);content.setColorFill(BaseColor.RED);content.setFontAndSize(font, 30);// 开始写入水印float pageWidth = reader.getPageSize(i).getWidth();float pageHigh = reader.getPageSize(i).getHeight();for (float heigh = 20; heigh < pageHigh; heigh += textH * 2) {for (float width = 20; width < pageWidth; width += textW + 30) {content.showTextAligned(Element.ALIGN_LEFT, waterMarkContent, width, heigh, -45);}}content.endText();}stamper.close();}
maven依赖：
<dependency><groupId>com.itextpdf</groupId><artifactId>itextpdf</artifactId><version>5.5.13</version></dependency>
