Microsoft Excel没有内置的水印功能。但是，有两种方法可以模拟水印的外观
..不幸的是，apache poi没有直接支持这些方法。
如果
XSSF仅是要求，则可以使用底层底层对象来在标题中编程图片
XSSF。
一个
*.xlsx文件只是一个
ZIP存档。因此，我们可以将其解压缩并查看内部结构。因此，创建一个
*.xlsx在标题中具有图片的文件，然后查看
*.xlsx
ZIP存档。
在
/xl/worksheets/sheet1.xml其中
XML找到工作表，我们发现类似：
...<headerFooter> <oddHeader>&C&G</oddHeader></headerFooter><legacyDrawingHF r:id="rId1"/>...
因此，我们
&G在
&Center标头中具有指向Graphic的点。并且我们有一个关系ID指向一个旧图纸。
我们在中找到的这张旧图
/xl/drawings/vmlDrawing1.vml。在此
*.vml文件中，还与中的图像有关
/xl/media/。
所以我们要做的是
- 将图像添加到工作簿。这实际上
apache poi
已经由提供。 将“＆G”放入中心标题。这实际上也是已经提供的
apache poi
。创建
/xl/drawings/vmlDrawing1.vml
为PackagePart
和创建POIXMLdocumentPart
提供了commit()
一种XML
在写出文件时将其保存到包中的方法。创建所有需要的关系。
以下代码是显示原理的工作草案。如图所示，我从链接的Microsoft支持页面下载了AF101880439_zh-
cn_draft.png。
该代码已完成并且可以正常工作，并创建一个
*.xlsx在第一张纸的中心标题中具有DRAFT图片的结果文件。
import java.io.*;import org.apache.poi.ss.usermodel.*;import org.apache.poi.xssf.usermodel.*;import org.apache.poi.util.IOUtils;import org.apache.poi.ss.util.ImageUtils;import org.apache.poi.openxml4j.opc.*;import org.apache.poi.POIXMLdocumentPart;import org.apache.xmlbeans.XmlObject;import static org.apache.poi.POIXMLTypeLoader.DEFAULT_XML_OPTIONS;public class CreateExcelPictureInHeaderAKAWatermark { static void createPictureForHeader(XSSFSheet sheet, int pictureIdx, String pictureTitle, int vmlIdx, String headerPos) throws Exception { OPCPackage opcpackage = sheet.getWorkbook().getPackage(); //creating /xl/drawings/vmlDrawing1.vml PackagePartName partname = PackagingURIHelper.createPartName("/xl/drawings/vmlDrawing" + vmlIdx+ ".vml"); PackagePart part = opcpackage.createPart(partname, "application/vnd.openxmlformats-officedocument.vmlDrawing"); //creating new VmlDrawing VmlDrawing vmldrawing = new VmlDrawing(part); //creating the relation to the picture in /xl/drawings/_rels/vmlDrawing1.vml.rels XSSFPictureData picData = sheet.getWorkbook().getAllPictures().get(pictureIdx); String rIdPic = vmldrawing.addRelation(null, XSSFRelation.IMAGES, picData).getRelationship().getId(); //get image dimension ByteArrayInputStream is = new ByteArrayInputStream(picData.getData()); java.awt.Dimension imageDimension = ImageUtils.getImageDimension(is, picData.getPictureType()); is.close(); //updating the VmlDrawing vmldrawing.setRIdPic(rIdPic); vmldrawing.setPictureTitle(pictureTitle); vmldrawing.setImageDimension(imageDimension); vmldrawing.setHeaderPos(headerPos); //creating the relation to /xl/drawings/vmlDrawing1.xml in /xl/worksheets/_rels/sheet1.xml.rels String rIdExtlink = sheet.addRelation(null, XSSFRelation.VML_DRAWINGS, vmldrawing).getRelationship().getId(); //creating the <legacyDrawingHF r:id="..."/> in /xl/worksheets/sheetN.xml sheet.getCTWorksheet().addNewLegacyDrawingHF().setId(rIdExtlink); } public static void main(String[] args) throws Exception { Workbook workbook = new XSSFWorkbook(); Sheet sheet; Header header; InputStream is; byte[] bytes; int pictureIdx; //we need it later sheet = workbook.createSheet(); header = sheet.getHeader(); header.setCenter("&G"); // &G means Graphic //add picture data to this workbook is = new FileInputStream("AF101880439_en-us_draft.png"); bytes = IOUtils.toByteArray(is); pictureIdx = workbook.addPicture(bytes, Workbook.PICTURE_TYPE_PNG); is.close(); //create header picture from picture data of this workbook createPictureForHeader((XSSFSheet)sheet, pictureIdx, "AF101880439_en-us_draft", 1, "CH"); FileOutputStream out = new FileOutputStream("CreateExcelPictureInHeader.xlsx"); workbook.write(out); out.close(); workbook.close(); } //class for VmlDrawing static class VmlDrawing extends POIXMLdocumentPart { String rIdPic = ""; String pictureTitle = ""; java.awt.Dimension imageDimension = null; String headerPos = ""; VmlDrawing(PackagePart part) { super(part); } void setRIdPic(String rIdPic) { this.rIdPic = rIdPic; } void setPictureTitle(String pictureTitle) { this.pictureTitle = pictureTitle; } void setHeaderPos(String headerPos) { this.headerPos = headerPos; } void setImageDimension(java.awt.Dimension imageDimension) { this.imageDimension = imageDimension; } @Override protected void commit() throws IOException { PackagePart part = getPackagePart(); OutputStream out = part.getOutputStream(); try { XmlObject doc = XmlObject.Factory.parse( "<xml xmlns:v="urn:schemas-microsoft-com:vml"" +" xmlns:o="urn:schemas-microsoft-com:office:office"" +" xmlns:x="urn:schemas-microsoft-com:office:excel">" +" <o:shapelayout v:ext="edit">" +" <o:idmap v:ext="edit" data="1"/>" +" </o:shapelayout><v:shapetype id="_x0000_t75" coordsize="21600,21600" o:spt="75"" +" o:preferrelative="t" path="m@4@5l@4@11@9@11@9@5xe" filled="f" stroked="f">" +" <v:stroke joinstyle="miter"/>" +" <v:formulas>" +" <v:f eqn="if lineDrawn pixelLineWidth 0"/>" +" <v:f eqn="sum @0 1 0"/>" +" <v:f eqn="sum 0 0 @1"/>" +" <v:f eqn="prod @2 1 2"/>" +" <v:f eqn="prod @3 21600 pixelWidth"/>" +" <v:f eqn="prod @3 21600 pixelHeight"/>" +" <v:f eqn="sum @0 0 1"/>" +" <v:f eqn="prod @6 1 2"/>" +" <v:f eqn="prod @7 21600 pixelWidth"/>" +" <v:f eqn="sum @8 21600 0"/>" +" <v:f eqn="prod @7 21600 pixelHeight"/>" +" <v:f eqn="sum @10 21600 0"/>" +" </v:formulas>" +" <v:path o:extrusionok="f" gradientshapeok="t" o:connecttype="rect"/>" +" <o:lock v:ext="edit" aspectratio="t"/>" +" </v:shapetype><v:shape id="" + headerPos + "" o:spid="_x0000_s1025" type="#_x0000_t75"" +" style='position:absolute;margin-left:0;margin-top:0;" +"width:" + (int)imageDimension.getWidth() + "px;height:" + (int)imageDimension.getHeight() + "px;" +"z-index:1'>" +" <v:imagedata o:relid=""+ rIdPic + "" o:title="" + pictureTitle + ""/>" +" <o:lock v:ext="edit" rotation="t"/>" +" </v:shape></xml>" ); doc.save(out, DEFAULT_XML_OPTIONS); out.close(); } catch (Exception ex) { ex.printStackTrace(); } } }}需要更改进口商品才能使用current进行工作
apache poi 4.0.1：
...//import org.apache.poi.POIXMLdocumentPart;import org.apache.poi.ooxml.POIXMLdocumentPart;import org.apache.xmlbeans.XmlObject;//import static org.apache.poi.POIXMLTypeLoader.DEFAULT_XML_OPTIONS;import static org.apache.poi.ooxml.POIXMLTypeLoader.DEFAULT_XML_OPTIONS;...
