无法从.xlsx单元读取RGB数据

Question

I have a simple .xlsx file which has cells of different colors. I need to get the colors and check if they are RED, YELLOW or GREEN.

The excel file looks like this:

For that I tried to write the code as following:

// get Cell color for specificed cells
        CellStyle cellStyle = currentCell.getCellStyle();
        XSSFCellStyle xssfCellStyle = (XSSFCellStyle) cellStyle;
        XSSFColor color = xssfCellStyle.getFillBackgroundXSSFColor();

        // check for null - when there is no cell background color, it returns null
        if (null != color) {
            String rgb =  color.getCTColor().getDomNode().getAttributes().getNamedItem("rgb").getNodeValue();
        }

This code throws NullPointerException, because, here color.getCTColor().getDomNode().getAttributes().getNamedItem("rgb") == null .

Then I worked on another approach which is following:

// get Cell color for specificed cells
        CellStyle cellStyle = currentCell.getCellStyle();
        XSSFCellStyle xssfCellStyle = (XSSFCellStyle) cellStyle;
        XSSFColor color = xssfCellStyle.getFillBackgroundXSSFColor();
        if (color != null) {
            cellObject.setBackgroundColor(color.getARGBHex());
            System.out.println("row: " + rowIndex + "col: " + colIndex + "color : " + color.getARGBHex());
        }

But, in this approach the the value for color.getARGBHex() in each cell as null .

Edit: I tried another simpler approach which is the following:

//get cell colors
        short style = currentCell.getCellStyle().getFillBackgroundColor();
        System.out.println("row:"+rowIndex+",col:"+colIndex+" color: "+style);

This code returns the value for every cell: 64

Edit: As per Axel's suggestion, I tried this code:

short xssfColor = currentCell.getCellStyle().getFillForegroundColor();

But, this code returns 64 for white cells and 0 for non-white cells.

Can anyone please help in this regard? Thanks in advance!

Answer 1

Thanks Axel for the hint. Using his hint, I was able to solve this problem.

I used this code for solving this problem.

// get cell colors
        XSSFColor xssfColor = (XSSFColor) currentCell.getCellStyle().getFillForegroundColorColor();
        if (xssfColor != null)
            System.out.println("row:" + rowIndex + ",col:" + colIndex + " color: " + xssfColor.getARGBHex());

This clearly differentiates between all the colors. getARGBHex() returns RGB components along with the Alpha value. But, it is easy string operation to extract the RGB from the data

For example:

Red : FFFF0000 (returned by getARGBMex() method, so RGB value is: FF0000).

Thanks again Axel for your help.