itext pdf添加文字水印 打印时水印遮住下面实体数据

for (int i = 1; i <= total; i++) // 每一页都加水印

            {

                pageWidth = reader.getPageSize(i).getWidth();

                pageHeight = reader.getPageSize(i).getHeight();

  

                under = stamp.getOverContent(i);

  

                // 加入文字

                // gs.setFillOpacity(10f);//设置透明度为0.8

                under.setGState(gs);

                under.setColorFill(BaseColor.RED);

                under.setFontAndSize(bfChinese, fontSize);

  

                under.beginText();

                // 用来设置文字的位置和字体---开始

                // 横向居中

                under.setTextMatrix(

                        (pageWidth - fontSize * stampStr.length()) / 2,

                        pageHeight - margin_top);

                // 用来设置文字的位置和字体---结束

                //换行输出水印

                for (int j = 0; j < lines_count; j++) {

                    String temp_line=stampArray.get(j);

                    if(temp_line!=null && temp_line.length()>0){

//                      under.showTextAligned(Element.ALIGN_CENTER, temp_line,

//                              pageWidth / 2, pageHeight / 2, Integer

//                                      .parseInt(StaticValue.Font_Rotation));

                                              //关键代码在这里---开始

                                               //先写入文字

                        under.showTextAligned(Element.ALIGN_CENTER, temp_line,

                                pageWidth / 2, pageHeight / 2-j*(fontSize+StaticValue.Stamp_Line_Length), Integer

                                        .parseInt(StaticValue.Font_Rotation));

                                          //关键代码在这里---结束

                                  

                    }

                }

                under.endText();

                under.saveState();

            }

----------------------------------------------------------------------循环加载图片

for (int i = 1; i <= total; i++) // 每一页都加水印

            {

                pageWidth = reader.getPageSize(i).getWidth();

                pageHeight = reader.getPageSize(i).getHeight();

  

                under = stamp.getOverContent(i);

                           for (int j = 0; j < lines_count; j++) {

                    String temp_line=stampArray.get(j);

                    if(temp_line!=null && temp_line.length()>0){

//                      under.showTextAligned(Element.ALIGN_CENTER, temp_line,

//                              pageWidth / 2, pageHeight / 2, Integer

//                                      .parseInt(StaticValue.Font_Rotation));

                                              //关键代码在这里---开始

                                //逐页写入图片

                                  under.setGState(gs);

                image.setAlignment(Image.UNDERLYING);//图片置底，而图片本身为透明图片

                image.setAbsolutePosition(0, 0);

                image.scaleAbsolute(pageWidth, pageHeight);//这里要注意，遮住整个page,即作为背景存在

                under.addImage(image);

                under.saveState();

                                              //关键代码在这里---结束

                                  

                    }

                }

                under.endText();

                under.saveState();

            }