读取文本文件并将字符串“ true / false”追加到现有行并使用Java覆盖文件,但是FileWriter无法解析

我的程序的目的是:

1)输入帐号并检查其是否存在于由帐号行组成的文本文件accs.txt中

2)输入文件的路径

3)读取文本文件的内容(如果存在输入),在每行后附加“ true”,否则添加“ false”,然后覆盖文件并给出输出。

我完成了大部分工作,但是不明白为什么FileWriter无法解决:

import java.io.*;
import java.util.*;
public class ReadFromFile2 
    {

    public static void main(String[] args) throws IOException {

        //create object of a text file
        File file = new File("C:\\Users\\Artur\\Desktop\\accs.txt");

        BufferedReader br = new BufferedReader(new FileReader(file));

        //ask for user account input
        System.out.println("Enter your account number:");
        Scanner input = new Scanner(System.in);
        String account = input.nextLine();

        //read the file and check if account exists
        String st;
        while ((st = br.readLine()) !=null) {
            if(st.contains(account)) 

                System.out.println("Found");

                else System.out.println("Not found");
            break;
            }

        //enter a filename accs.txt and the path
        System.out.println("Enter file name:");
        Scanner inputname = new Scanner(System.in);
        String filename = input.nextLine();

        System.out.println("Enter path for file accs:");
        Scanner inputpath = new Scanner(System.in);
        String path = input.nextLine();

        //return path
        File fileaccounts = new File(path + "\\" + filename);
        System.out.println(fileaccounts);

        //read results,if exists - true,if not - false,then write file
        FileWriter fw = new FileWriter(file,true);

        BufferedWriter bw = new BufferedWriter(fw);
        String fileContent = "accs.txt";
        int lineNum = 0;

         while ((st = br.readLine()) != null) {

             if(st.contains(account))

                 st = st +"; true";

             else st = st +"; false";
             lineNum++;
             System.out.println(st);
             fileWriter.write(st);

             //FileWriter fw = new FileWriter("C:\\Users\\Artur\\Desktop\\newfile.txt");
             //fw.write(fileContent);
             fw.close();




         }
        }
    }

预期输出应为:

Enter your account number:
AA051245445454552117989
Found
Enter file name:
accs.txt
Enter path for file accs:
C:\Users\Artur\Desktop\\accs.txt
C:\Users\Artur\Desktop\accs.txt\accs.txt
LT647044001231465456; false
LT517044077788877777; false
LT227044077788877777; false
CC051245445454552117989; false

但是我修改了当前示例的代码,然后得到了

Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
    fileWriter cannot be resolved

    at ReadFromFile2.main(ReadFromFile2.java:58)

PS:谢谢您的回答,这是我的一个小错误,但是我仍然无法使程序覆盖文件。有什么建议吗?

ASD52113144 回答:读取文本文件并将字符串“ true / false”追加到现有行并使用Java覆盖文件,但是FileWriter无法解析

您将FileWriter对象声明为fw

FileWriter fw = new FileWriter(file,true);

但是您尝试将其用作fileWriter

fileWriter.write(st);

您的代码中没有创建fileWriter变量,因此会出现错误

,
FileWriter fw = new FileWriter(file,true);

已定义,并且还定义了BufferedWriter:

BufferedWriter bw = new BufferedWriter(fw);

因此,不要调用fileWriter,而是执行以下操作:

bw.write(st);
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