POI library update excel picture

   Updating pictures includes deleting old pictures , New picture insert .
   however , Go to POI Of API When you look for relevant content inside , It's only easier to find a way to add pictures , It's hard to find a way to delete pictures . And there are few related deletions on the Internet , Searching for a long time , from Stack Overflow Found a more reliable method on , as follows ：

public static void deleteCTAnchor(XSSFPicture xssfPicture) {
    
  XSSFDrawing drawing = xssfPicture.getDrawing();
  XmlCursor cursor = xssfPicture.getCTPicture().newCursor();
  cursor.toParent();
  if (cursor.getObject() instanceof org.openxmlformats.schemas.drawingml.x2006.spreadsheetDrawing.CTTwoCellAnchor) {
    
   for (int i = 0; i < drawing.getCTDrawing().getTwoCellAnchorList().size(); i++) {
    
    if (cursor.getObject().equals(drawing.getCTDrawing().getTwoCellAnchorArray(i))) {
    
     drawing.getCTDrawing().removeTwoCellAnchor(i);
     System.out.println("TwoCellAnchor for picture " + xssfPicture + " was deleted.");
    }
   }
  } else if (cursor.getObject() instanceof org.openxmlformats.schemas.drawingml.x2006.spreadsheetDrawing.CTOneCellAnchor) {
    
   for (int i = 0; i < drawing.getCTDrawing().getOneCellAnchorList().size(); i++) {
    
    if (cursor.getObject().equals(drawing.getCTDrawing().getOneCellAnchorArray(i))) {
    
     drawing.getCTDrawing().removeOneCellAnchor(i);
     System.out.println("OneCellAnchor for picture " + xssfPicture + " was deleted.");
    }
   }
  } else if (cursor.getObject() instanceof org.openxmlformats.schemas.drawingml.x2006.spreadsheetDrawing.CTAbsoluteAnchor) {
    
   for (int i = 0; i < drawing.getCTDrawing().getAbsoluteAnchorList().size(); i++) {
    
    if (cursor.getObject().equals(drawing.getCTDrawing().getAbsoluteAnchorArray(i))) {
    
     drawing.getCTDrawing().removeAbsoluteAnchor(i);
     System.out.println("AbsoluteAnchor for picture " + xssfPicture + " was deleted.");
    }
   }
  }
 }

 public static void deleteEmbeddedXSSFPicture(XSSFPicture xssfPicture) {
    
  if (xssfPicture.getCTPicture().getBlipFill() != null) {
    
   if (xssfPicture.getCTPicture().getBlipFill().getBlip() != null) {
    
    if (xssfPicture.getCTPicture().getBlipFill().getBlip().getEmbed() != null) {
    
     String rId = xssfPicture.getCTPicture().getBlipFill().getBlip().getEmbed();
     XSSFDrawing drawing = xssfPicture.getDrawing();
     drawing.getPackagePart().removeRelationship(rId);
     drawing.getPackagePart().getPackage().deletePartRecursive(drawing.getRelationById(rId).getPackagePart().getPartName());
     System.out.println("Picture " + xssfPicture + " was deleted.");
    }
   }
  }
 }

 public static void deleteHSSFShape(HSSFShape shape) {
    
  HSSFPatriarch drawing = shape.getPatriarch();
  drawing.removeShape(shape);    
  System.out.println("Shape " + shape + " was deleted.");
 }

   The author says , If you want to delete .xlsx The photos in , Need to delete its relations and anchor, And it's used poi 4.0.1 Test done
   But my side is Android The project does not use 4.0.1 Version of , I'm using 3.9 Version of the library and related jar, The operation is also .xlsx Format . When relevant methods are adopted , It's a mistake , First, some classes and methods cannot be found , This can be commented out first , After testing , It's really not used . There are other methods in operation , That's what makes a mistake , Also, the relevant classes used cannot be found . Through source code comparison , Found the corresponding alternative method . The modified , In fact, the main revision is deleteCTAnchor The method inside , The modified method is as follows ：

    public static void deleteCTAnchor(XSSFPicture xssfPicture) {
    
        XSSFDrawing drawing = xssfPicture.getDrawing();
        XmlCursor cursor = xssfPicture.getCTPicture().newCursor();
        cursor.toParent();
        if (cursor.getObject() instanceof org.openxmlformats.schemas.drawingml.x2006.spreadsheetDrawing.CTTwoCellAnchor) {
    
            int len = drawing.getCTDrawing().getTwoCellAnchorArray().length;
            int seleIn = -1;
            for (int i = 0; i < len; i++) {
    
                if (cursor.getObject().equals(drawing.getCTDrawing().getTwoCellAnchorArray(i))) {
    
                    seleIn = i;
                    System.out.println("TwoCellAnchor for picture " + xssfPicture + " was deleted.seleIn:" + i);
                    break;
                }
            }
            if (seleIn != -1) {
    
                drawing.getCTDrawing().removeTwoCellAnchor(seleIn);
            }
        } else if (cursor.getObject() instanceof org.openxmlformats.schemas.drawingml.x2006.spreadsheetDrawing.CTOneCellAnchor) {
    
            int len = drawing.getCTDrawing().getOneCellAnchorArray().length;
            int seleIn = -1;
            for (int i = 0; i < len; i++) {
    
                if (cursor.getObject().equals(drawing.getCTDrawing().getOneCellAnchorArray(i))) {
    
                    seleIn = i;
                    System.out.println("OneCellAnchor for picture " + xssfPicture + " was deleted.");
                    break;
                }
            }
            if (seleIn != -1) {
    
                drawing.getCTDrawing().removeOneCellAnchor(seleIn);
            }
        }
    }

   Now the way to update the image is as follows ：

    public static void updateXssfImg(Workbook wookbook,
                                                 Sheet sheet, String filePath, byte[] imgBytes,int row, int col, XSSFPicture xssfPicture) {
    
        Log.e(TAG,"updateXssfImg, Row number ：" + row + ", Number of columns ：" + col+ ", Time :" + System.currentTimeMillis());
        Drawing dg = sheet.createDrawingPatriarch();

            deleteEmbeddedXSSFPicture(xssfPicture);
            deleteCTAnchor(xssfPicture);

            XSSFClientAnchor anchor = new XSSFClientAnchor(0,0,255,255, col, row,col+1,row+1);
            anchor.setAnchorType(3);
            // Insert a picture 
            dg.createPicture(anchor, wookbook.addPicture(imgBytes, XSSFWorkbook.PICTURE_TYPE_JPEG));

        FileOutputStream  fileOut = null;
        try {
    
            fileOut = new FileOutputStream(filePath);
            //  write in excel file 
            wookbook.write(fileOut);
            Log.e(TAG, "----Excle File image Dele Updated ------"+ ", Time :" + System.currentTimeMillis());


        } catch(IOException e) {
    
            e.printStackTrace();
        } finally {
    
            if(fileOut != null) {
    
                try {
    
                    fileOut.close();
                } catch (IOException e) {
    
                    e.printStackTrace();
                }
            }
        }
    }

   It can really be updated .xlsx The picture in the picture , But the problem is , An exception will occur when the update is performed again , Cause crash . Tracking through code , Found to be wookbook.addPicture(imgBytes, XSSFWorkbook.PICTURE_TYPE_JPEG) There is an exception in this code ,A part with the name ‘XXXXXX’ already exists, Guess when the deletion might start , Some relevant contents have been deleted by mistake , Cause another execution error . Because I used to delete pictures before , Because the method was not found , So it's all right anchor Actions performed , No other operation , So I tried to delete only anchor Methods , Do not delete relations The operation of , Find it feasible . After repeated updates , The original picture was deleted . So the final solution is to deleteEmbeddedXSSFPicture(xssfPicture) Method delete , as follows ：

    public static void updateXssfImg(Workbook wookbook,
                                                 Sheet sheet, String filePath, byte[] imgBytes,int row, int col, XSSFPicture xssfPicture) {
    
        Log.e(TAG,"updateXssfImg, Row number ：" + row + ", Number of columns ：" + col+ ", Time :" + System.currentTimeMillis());
        Drawing dg = sheet.createDrawingPatriarch();

            deleteCTAnchor(xssfPicture);

            XSSFClientAnchor anchor = new XSSFClientAnchor(0,0,255,255, col, row,col+1,row+1);
            anchor.setAnchorType(3);
            // Insert a picture 
            dg.createPicture(anchor, wookbook.addPicture(imgBytes, XSSFWorkbook.PICTURE_TYPE_JPEG));

        FileOutputStream  fileOut = null;
        try {
    
            fileOut = new FileOutputStream(filePath);
            //  write in excel file 
            wookbook.write(fileOut);
            Log.e(TAG, "----Excle File image Dele Updated ------"+ ", Time :" + System.currentTimeMillis());


        } catch(IOException e) {
    
            e.printStackTrace();
        } finally {
    
            if(fileOut != null) {
    
                try {
    
                    fileOut.close();
                } catch (IOException e) {
    
                    e.printStackTrace();
                }
            }
        }
    }

   All right , The final plan is like this .