poi的shiftRows方法解释

sheet.shiftRows(6, 12, -5);

从第6（在excel中指第7行）行到第12（在excel中指第13行）行全部向上移5行

例如，我想把表格除了第一行以外的内容都清空

public  void deleteRow(String filePath){
        //只支持Excel 2007/2010
        try {
            FileInputStream is = new FileInputStream(filePath);
            XSSFWorkbook workbook = new XSSFWorkbook(is);
            XSSFSheet sheet = workbook.getSheetAt(0);
            sheet.shiftRows(sheet.getLastRowNum()+1, sheet.getLastRowNum()*2, -sheet.getLastRowNum());//删除第2行到第300行，然后使下方单元格上移
            FileOutputStream os = new FileOutputStream(filePath);
            workbook.write(os);
            is.close();
            os.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }