java无法将数据附加到现有excel中

Question

我无法将数据附加到现有的Excel工作表中
这是我的代码：

fis = new FileInputStream(file);
fs = new POIFSFileSystem(fis);
HSSFWorkbook wb1 = new HSSFWorkbook(fs);
sheet1 = wb1.getSheet("sheet1");
System.out.println("Last Row No.: " + sheet1.getLastRowNum());
row = sheet1.createRow(sheet1.getLastRowNum()+ 1);
System.out.println("Last Row No.: " + sheet1.getLastRowNum());

row.createCell(0).setCellValue(2);          
row.createCell(1).setCellValue(2.2);
row.createCell(2).setCellValue(true);   

fos = new FileOutputStream(file,true);
wb1.write(fos);
fos.flush();
fos.close();

Answer 1

excel文件格式不是可追加的格式。要写出更改，必须更新整个文件

只需将FileOutputStream更改为替换文件而不是附加文件，代码就应该按照预期的方式运行

Answer 2

尝试使用此代码追加

fis = new FileInputStream(file);
Workbook wb=WorkbookFactory.create(fis);
sheet1 = wb1.getSheet("sheet1");
System.out.println("Last Row No.: " + sheet1.getLastRowNum());
row = sheet1.createRow(sheet1.getLastRowNum()+ 1);
System.out.println("Last Row No.: " + sheet1.getLastRowNum());

row.createCell(0).setCellValue(2);          
row.createCell(1).setCellValue(2.2);
row.createCell(2).setCellValue(true);   

fos = new FileOutputStream(file,true);
wb1.write(fos);
fos.flush();
fos.close();