How do I know if a cell returns a null value while reading an Excel Sheet?

Question

I am reading values from some specific cells in an excel sheet. Those cells generally contain String but sometimes they may be blank (thus may return a blank or a null). I am using the following code to get the cell data:

Cell cellValue = row.getCell(10, Row.RETURN_NULL_AND_BLANK);
List.add(cellValue.getStringCellValue());

However, when I run this code I get a NullPointerException. Can anybody point out what is wrong and should be added?

Note: I am deliberately using Row.RETURN_NULL_AND_BLANK and not MissingCellPolicy.RETURN_NULL_AND_BLANK because using the latter was giving me an error.

Answer 1

You need to test the cellValue if it is not null, since using Row.RETURN_NULL_AND_BLANK will return null in cases where you are trying to access a missing cell.

You are getting a NullPointerException because the 10-th column on a specified row is missing.

If you need to handle differently the missing vs. blank cases you can use the following:

Cell cellValue = row.getCell(10, Row.RETURN_NULL_AND_BLANK);
if (cellValue == null)
    List.add("CELL NOT FOUND");
else if("".equals(cellValue.getStringCellValue().trim()))
    List.add("MISSING CONTENT");
else 
    List.add(cellValue.getStringCellValue());

Answer 2

@dan - Thanks for your reply. That indeed helped. I modified my code as follows and I am not getting that exception now:

Cell cellValue = row.getCell(10, Row.CREATE_NULL_AS_BLANK);
if(cellValue.getStringCellValue().equals("")){
    List.add("NOT FOUND");
}
else {
    List.add(cellValue.getStringCellValue());
}