Add a watermark with Apache POI to a docx that already have a header - apache-poi

Question

How can I add a watermark to a docx file that already have a header.
All the examples code show how to add to a doc with an empty header, but if the document already have one, the code fail.
The main issue is in XWPFHeaderFooterPolicy.createHeader(..) because it ignore the call if a header exist, so the paragraph with the watermark info is not added.
public XWPFHeader createHeader(Enum type, XWPFParagraph[] pars) {
XWPFHeader header = getHeader(type);
if (header == null) {
HdrDocument hdrDoc = HdrDocument.Factory.newInstance();
XWPFRelation relation = XWPFRelation.HEADER;
int i = getRelationIndex(relation);
XWPFHeader wrapper = (XWPFHeader) doc.createRelationship(relation,
XWPFFactory.getInstance(), i);
wrapper.setXWPFDocument(doc);
CTHdrFtr hdr = buildHdr(type, wrapper, pars);
wrapper.setHeaderFooter(hdr);
hdrDoc.setHdr(hdr);
assignHeader(wrapper, type);
header = wrapper;
}
return header;
}
When createWatermark call that method, it simply enter and out doing nothing.
I do not found a way to do the same. How could I correct this?

Answer 1

The XWPFHeaderFooterPolicy.createHeader is only used to create new headers. If headers are already present, then nothing will be changed in those headers.
If you look into the source code of XWPFHeaderFooterPolicy, as you had done already, you will see that the watermark simply is a WordArt shape within a paragraph in the header. So you simply could create that kind of WordArt shape in a already existant paragraph in a header. To do so try to understand XWPFHeaderFooterPolicy.getWatermarkParagraph(String text, int idx) and rewrite it into a setWatermarkInParagraph(XWPFParagraph paragraph, String text). Then you can get or create a paragraph in any header you want and put the watermark into that paragraph.
Following complete example shows this. It works using apache poi 5.0.0. Using apache poi 3.17 or apache poi 4.1.2 the commented changes in import statements need to be done.
import java.io.*;
import org.apache.poi.xwpf.usermodel.*;
import org.apache.poi.wp.usermodel.HeaderFooterType;
import org.openxmlformats.schemas.wordprocessingml.x2006.main.*;
import org.openxmlformats.schemas.wordprocessingml.x2006.main.CTR;
import com.microsoft.schemas.office.office.*;
import com.microsoft.schemas.office.office.CTLock;
import com.microsoft.schemas.vml.*;
import org.openxmlformats.schemas.officeDocument.x2006.sharedTypes.STTrueFalse; // apache ppi 5.0.0
//import com.microsoft.schemas.vml.STTrueFalse; // apache poi 3.17 and apache poi 4.1.2
public class CreateWordHeaderWatermarkInExistingDocument {
private static void setWatermarkInParagraph(XWPFParagraph paragraph, String text) {
//CTP p = CTP.Factory.newInstance();
CTP p = paragraph.getCTP();
XWPFDocument doc = paragraph.getDocument();
CTBody ctBody = doc.getDocument().getBody();
byte[] rsidr = null;
byte[] rsidrdefault = null;
if (ctBody.sizeOfPArray() == 0) {
// TODO generate rsidr and rsidrdefault
} else {
CTP ctp = ctBody.getPArray(0);
rsidr = ctp.getRsidR();
rsidrdefault = ctp.getRsidRDefault();
}
p.setRsidP(rsidr);
p.setRsidRDefault(rsidrdefault);
CTPPr pPr = p.getPPr(); if (pPr == null) pPr = p.addNewPPr();
CTString pStyle = pPr.getPStyle(); if (pStyle == null) pStyle = pPr.addNewPStyle();
pStyle.setVal("Header");
// start watermark paragraph
CTR r = p.addNewR();
CTRPr rPr = r.addNewRPr();
rPr.addNewNoProof();
int idx = 1;
CTPicture pict = r.addNewPict();
CTGroup group = CTGroup.Factory.newInstance();
CTShapetype shapetype = group.addNewShapetype();
shapetype.setId("_x0000_t136");
shapetype.setCoordsize("1600,21600");
shapetype.setSpt(136);
shapetype.setAdj("10800");
shapetype.setPath2("m#7,0l#8,0m#5,21600l#6,21600e");
CTFormulas formulas = shapetype.addNewFormulas();
formulas.addNewF().setEqn("sum #0 0 10800");
formulas.addNewF().setEqn("prod #0 2 1");
formulas.addNewF().setEqn("sum 21600 0 #1");
formulas.addNewF().setEqn("sum 0 0 #2");
formulas.addNewF().setEqn("sum 21600 0 #3");
formulas.addNewF().setEqn("if #0 #3 0");
formulas.addNewF().setEqn("if #0 21600 #1");
formulas.addNewF().setEqn("if #0 0 #2");
formulas.addNewF().setEqn("if #0 #4 21600");
formulas.addNewF().setEqn("mid #5 #6");
formulas.addNewF().setEqn("mid #8 #5");
formulas.addNewF().setEqn("mid #7 #8");
formulas.addNewF().setEqn("mid #6 #7");
formulas.addNewF().setEqn("sum #6 0 #5");
CTPath path = shapetype.addNewPath();
path.setTextpathok(STTrueFalse.T);
path.setConnecttype(STConnectType.CUSTOM);
path.setConnectlocs("#9,0;#10,10800;#11,21600;#12,10800");
path.setConnectangles("270,180,90,0");
CTTextPath shapeTypeTextPath = shapetype.addNewTextpath();
shapeTypeTextPath.setOn(STTrueFalse.T);
shapeTypeTextPath.setFitshape(STTrueFalse.T);
CTHandles handles = shapetype.addNewHandles();
CTH h = handles.addNewH();
h.setPosition("#0,bottomRight");
h.setXrange("6629,14971");
CTLock lock = shapetype.addNewLock();
lock.setExt(STExt.EDIT);
CTShape shape = group.addNewShape();
shape.setId("PowerPlusWaterMarkObject" + idx);
shape.setSpid("_x0000_s102" + (4 + idx));
shape.setType("#_x0000_t136");
shape.setStyle("position:absolute;margin-left:0;margin-top:0;width:415pt;height:207.5pt;z-index:-251654144;mso-wrap-edited:f;mso-position-horizontal:center;mso-position-horizontal-relative:margin;mso-position-vertical:center;mso-position-vertical-relative:margin");
shape.setWrapcoords("616 5068 390 16297 39 16921 -39 17155 7265 17545 7186 17467 -39 17467 18904 17467 10507 17467 8710 17545 18904 17077 18787 16843 18358 16297 18279 12554 19178 12476 20701 11774 20779 11228 21131 10059 21248 8811 21248 7563 20975 6316 20935 5380 19490 5146 14022 5068 2616 5068");
shape.setFillcolor("#d8d8d8");
shape.setStyle(shape.getStyle() + ";rotation:315");
shape.setStroked(STTrueFalse.FALSE);
CTTextPath shapeTextPath = shape.addNewTextpath();
shapeTextPath.setStyle("font-family:"Cambria";font-size:1pt");
shapeTextPath.setString(text);
pict.set(group);
}
public static void main(String[] args) throws Exception {
//XWPFDocument doc= new XWPFDocument();
XWPFDocument doc= new XWPFDocument(new FileInputStream("./WordDocument.docx"));
// the body content
XWPFParagraph paragraph = doc.createParagraph();
XWPFRun run=paragraph.createRun();
run.setText("New text in body.");
// get or create the default header
XWPFHeader header = doc.createHeader(HeaderFooterType.DEFAULT);
// get or create first paragraph in first header
paragraph = header.getParagraphArray(0);
if (paragraph == null) paragraph = header.createParagraph();
// set watermark to that paragraph
setWatermarkInParagraph(paragraph, "Watermark default");
header = doc.createHeader(HeaderFooterType.EVEN);
paragraph = header.getParagraphArray(0);
if (paragraph == null) paragraph = header.createParagraph();
setWatermarkInParagraph(paragraph, "Watermark even");
header = doc.createHeader(HeaderFooterType.FIRST);
paragraph = header.getParagraphArray(0);
if (paragraph == null) paragraph = header.createParagraph();
setWatermarkInParagraph(paragraph, "Watermark first");
FileOutputStream out = new FileOutputStream("./WordDocumentWithWatermark.docx");
doc.write(out);
out.close();
doc.close();
}
}

Answer 2

Based on the excellent answer of Axel I wrote this code:
public DocumentTools addWatermark(String watermark) throws IOException {
addWatermark(watermark, "#d8d8d8", 315, HeaderFooterType.DEFAULT);
return this;
}
public DocumentTools addWatermark(String watermark, String color, float rotation, HeaderFooterType... hft) throws IOException {
if (hft.length == 0) {
hft = new HeaderFooterType[1];
hft[0] = HeaderFooterType.DEFAULT;
}
for (HeaderFooterType headerFooterType : hft) {
// get or create the default header
XWPFHeader header = doc.createHeader(headerFooterType);
// get or create first paragraph in first header
XWPFParagraph paragraph = header.getParagraphArray(0);
if (paragraph == null) {
paragraph = header.createParagraph();
}
// set watermark to that paragraph
setWatermarkInParagraph(paragraph, watermark, color, rotation);
}
return this;
}
//=====================================================
// Axel code with a minimal fix for color and rotation parameters.
//=====================================================
private static void setWatermarkInParagraph(XWPFParagraph paragraph, String text, String color, float rotation) {
//CTP p = CTP.Factory.newInstance();
CTP p = paragraph.getCTP();
XWPFDocument doc = paragraph.getDocument();
CTBody ctBody = doc.getDocument().getBody();
byte[] rsidr = null;
byte[] rsidrdefault = null;
if (ctBody.sizeOfPArray() == 0) {
// TODO generate rsidr and rsidrdefault
} else {
CTP ctp = ctBody.getPArray(0);
rsidr = ctp.getRsidR();
rsidrdefault = ctp.getRsidRDefault();
}
p.setRsidP(rsidr);
p.setRsidRDefault(rsidrdefault);
CTPPr pPr = p.getPPr();
if (pPr == null) {
pPr = p.addNewPPr();
}
CTString pStyle = pPr.getPStyle();
if (pStyle == null) {
pStyle = pPr.addNewPStyle();
}
pStyle.setVal("Header");
// start watermark paragraph
CTR r = p.addNewR();
CTRPr rPr = r.addNewRPr();
rPr.addNewNoProof();
int idx = 1;
CTPicture pict = r.addNewPict();
CTGroup group = CTGroup.Factory.newInstance();
CTShapetype shapetype = group.addNewShapetype();
shapetype.setId("_x0000_t136");
shapetype.setCoordsize("1600,21600");
shapetype.setSpt(136);
shapetype.setAdj("10800");
shapetype.setPath2("m#7,0l#8,0m#5,21600l#6,21600e");
CTFormulas formulas = shapetype.addNewFormulas();
formulas.addNewF().setEqn("sum #0 0 10800");
formulas.addNewF().setEqn("prod #0 2 1");
formulas.addNewF().setEqn("sum 21600 0 #1");
formulas.addNewF().setEqn("sum 0 0 #2");
formulas.addNewF().setEqn("sum 21600 0 #3");
formulas.addNewF().setEqn("if #0 #3 0");
formulas.addNewF().setEqn("if #0 21600 #1");
formulas.addNewF().setEqn("if #0 0 #2");
formulas.addNewF().setEqn("if #0 #4 21600");
formulas.addNewF().setEqn("mid #5 #6");
formulas.addNewF().setEqn("mid #8 #5");
formulas.addNewF().setEqn("mid #7 #8");
formulas.addNewF().setEqn("mid #6 #7");
formulas.addNewF().setEqn("sum #6 0 #5");
CTPath path = shapetype.addNewPath();
path.setTextpathok(STTrueFalse.T);
path.setConnecttype(STConnectType.CUSTOM);
path.setConnectlocs("#9,0;#10,10800;#11,21600;#12,10800");
path.setConnectangles("270,180,90,0");
CTTextPath shapeTypeTextPath = shapetype.addNewTextpath();
shapeTypeTextPath.setOn(STTrueFalse.T);
shapeTypeTextPath.setFitshape(STTrueFalse.T);
CTHandles handles = shapetype.addNewHandles();
CTH h = handles.addNewH();
h.setPosition("#0,bottomRight");
h.setXrange("6629,14971");
CTLock lock = shapetype.addNewLock();
lock.setExt(STExt.EDIT);
CTShape shape = group.addNewShape();
shape.setId("PowerPlusWaterMarkObject" + idx);
shape.setSpid("_x0000_s102" + (4 + idx));
shape.setType("#_x0000_t136");
shape.setStyle("position:absolute;margin-left:0;margin-top:0;width:415pt;height:207.5pt;z-index:-251654144;mso-wrap-edited:f;mso-position-horizontal:center;mso-position-horizontal-relative:margin;mso-position-vertical:center;mso-position-vertical-relative:margin");
shape.setWrapcoords("616 5068 390 16297 39 16921 -39 17155 7265 17545 7186 17467 -39 17467 18904 17467 10507 17467 8710 17545 18904 17077 18787 16843 18358 16297 18279 12554 19178 12476 20701 11774 20779 11228 21131 10059 21248 8811 21248 7563 20975 6316 20935 5380 19490 5146 14022 5068 2616 5068");
shape.setFillcolor(color);
shape.setStyle(shape.getStyle() + ";rotation:"+rotation);
shape.setStroked(STTrueFalse.FALSE);
CTTextPath shapeTextPath = shape.addNewTextpath();
shapeTextPath.setStyle("font-family:"Cambria";font-size:1pt");
shapeTextPath.setString(text);
pict.set(group);
}