java - 如何附加到 RandomAccessFile？每次我运行这段代码时，数据都会被覆盖

Question

如何使用这段代码附加数据？每次运行代码时，数据总是被覆盖。

    try{
        RandomAccessFile fileWriter = new RandomAccessFile("Officers.txt", "rw");

        fileWriter.writeUTF(officerObject.getOfficerBadgeNum());
        fileWriter.writeUTF(officerObject.getOfficerFirstName());
        fileWriter.writeUTF(officerObject.getOfficerLastName());
        fileWriter.writeUTF(officerObject.getOfficerPrecint());

        fileWriter.close();
        System.out.println("Data Successfully Saved");
    }
    catch (IOException e) {
        System.out.println("Error in File. Could not SAVE Officer");
        e.printStackTrace();
    }

Answer 1

在你写之前，seek到文件末尾；第一个电话length .我也更喜欢 try-with-resources .喜欢，

try (RandomAccessFile fileWriter = new RandomAccessFile("Officers.txt", "rw")) {
    fileWriter.seek(fileWriter.length());
    fileWriter.writeUTF(officerObject.getOfficerBadgeNum());
    fileWriter.writeUTF(officerObject.getOfficerFirstName());
    fileWriter.writeUTF(officerObject.getOfficerLastName());
    fileWriter.writeUTF(officerObject.getOfficerPrecint());
    System.out.println("Data Successfully Saved");
} catch (IOException e) {
    System.out.println("Error writing File. Could not SAVE Officer");
    e.printStackTrace();
}