BufferedWriter写入现有文件

Question

我正在尝试创建一个程序,将文本保存在文件上,然后将文本添加到文件中.但是,每次我尝试写入文件时,它都会覆盖它并且不会写任何内容.我需要它来添加我想要的任何信息.

    FileReader input;
    BufferedReader readFile;

    FileWriter output;
    BufferedWriter writeFile;

    try {
    //  input = new FileReader(password_file);
        //readFile = new BufferedReader(input);

        output = new FileWriter(password_file);
        writeFile = new BufferedWriter(output);


        //while ((temp_user= readFile.readLine()) !=null) {
            //temp_pass = readFile.readLine();
        //}

        temp_user = save_prompt.getText();

        temp_pass = final_password;

                                        //Writes to the file
        writeFile.write(temp_user);
        writeFile.newLine();
        writeFile.write(temp_pass);

    }
    catch(IOException e) {
        System.err.println("Error: " + e.getMessage());
    }
}

Answer 1

你寻求的是追加模式.

new FileWriter(file,true); // true = append, false = overwrite

Answer 2

用新内容替换所有现有内容.

new FileWriter(file);

保留现有内容并将新内容附加到文件末尾.

new FileWriter(file,true);

例:

    FileWriter fileWritter = new FileWriter(file.getName(),true);
        BufferedWriter bufferWritter = new BufferedWriter(fileWritter);
        bufferWritter.write(data);
        bufferWritter.close();