When I am trying to update existing excel file I am encountering following error:
Exception in thread "main" java.lang.NullPointerException
at xltest.main(xltest.java:28)
My code:
FileInputStream file = new FileInputStream(new File("C:\\Users\\onu\\test.xlsx"));
XSSFWorkbook workbook = new XSSFWorkbook(file);
XSSFSheet sheet = workbook.getSheetAt(0);
//Update the value of cell
Cell cell = sheet.getRow(0).getCell(3); // cell D1
cell.setCellValue("onu"); // line 28 which throws NPE
file.close();
FileOutputStream outFile =new FileOutputStream(new File("C:\\Users\\onu\\test.xlsx"));
workbook.write(outFile);
outFile.close();