java.io.FileInputStream file is getting generated on calling excel reader using XSSFWorkbook

Question

I am facing an issue where everytime path is initialized to XSSFWorkbook, a file java.io.FileInputStream@51bde877 (51bde877 being a random number each time) is created in the root folder of my project. Below is the sample code:

       try {
            fis = new FileInputStream(path);
            if (path.endsWith(".xls")) {
                workbook = new HSSFWorkbook(fis);
            }
            if (path.endsWith(".xlsx")) {
                workbook = new XSSFWorkbook(path);
            }

            if (rowNum <= 0)
                return false;

            int index = workbook.getSheetIndex(sheetName);
            if (index == -1)
                return false;

            sheet = workbook.getSheetAt(index);

            int colNum = -1;
            row = sheet.getRow(0);
            for (int i = 0; i < row.getLastCellNum(); i++) {
                //   System.out.println(row.getCell(i).getStringCellValue().trim());
                if (row.getCell(i).getStringCellValue().trim().equals(colName))
                    colNum = i;
            }

            if (colNum == -1)
                return false;

            sheet.autoSizeColumn(colNum);
            row = sheet.getRow(rowNum - 1);
            if (row == null)
                row = sheet.createRow(rowNum - 1);

            cell = row.getCell(colNum);
            if (cell == null)
                cell = row.createCell(colNum);

            cell.setCellValue(data);

            //fis.close();

            fileOut = new FileOutputStream(String.valueOf(new FileInputStream(path)));

            workbook.write(fileOut);
            fileOut.flush();
            workbook.close();

        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }

How should I prevent the creation of these junk files in my project?