正在写入CSV文件，无法写入第一行

Question

try{
      Writer rwrite = new BufferedWriter(new FileWriter(file, true));
      rwrite.append(reservation.toString() + "\n");
      rwrite.close();
    }
    catch(IOException e){
      System.out.println("Could not open BufferedWriter.");
      e.printStackTrace();
    }

我的意思是，基本上我的问题是我无法写入空的csv文件的第一行。我可以写第二个就好。也就是说，如果我自己手动输入了第一行，则可以写第二行。

任何人都可以帮助赞赏的人们，真的，很高兴。我很困惑。

更新：

try{

     File file = new File("reservations.csv");
     Scanner fileIn = new Scanner(file);

    try {
        if(fileIn.hasNext()){
        PrintWriter printWriter = new PrintWriter(new FileWriter("reservations.csv", true));
        printWriter.write(reservation.toString() + "\n");
        printWriter.close();
        }

        if(!fileIn.hasNext()){


            PrintWriter printWriter = new PrintWriter(new FileWriter("reservations.csv"));
            printWriter.write(reservation.toString() + "\n");
            printWriter.close();
        } 
        } catch (IOException e) {
            System.out.println("Could not open BufferedWriter.");
            e.printStackTrace();
        }


    }
    catch(IOException e){
     System.out.println("Error: failed to read from: " + "reservations.csv");
     e.printStackTrace();
    }

我将代码更改为此，并且此方法可行，但对我来说似乎有点怪异哈哈。无论如何，感谢您的帮助，仍会继续阅读。

Answer 1

尝试一下：-

try (PrintWriter printWriter = new PrintWriter(new FileWriter(file, true))) {
            printWriter.write(reservation.toString());
        } catch (IOException e) {
            logger.error("Error encountered whilst writing the file. Error : ", e);  e.printStackTrace();
        }