Scanner 클래스를 사용하여 Java 파일의 한 줄씩 읽기 및 쓰기 작업 구현

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class ReadFileExample {
    public static void main(String[] args) {
        // 指定文件路径
        File file = new File("test.txt");

        try {
            // 使用Scanner类读取文件
            Scanner scanner = new Scanner(file);

            // 逐行读取文件内容
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                System.out.println(line);
            }

            // 关闭Scanner对象
            scanner.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
}

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

public class WriteFileExample {
    public static void main(String[] args) {
        // 指定文件路径
        File file = new File("output.txt");

        try {
            // 创建FileWriter对象
            FileWriter writer = new FileWriter(file);

            // 使用Scanner类读取用户输入
            Scanner scanner = new Scanner(System.in);

            // 逐行写入文件
            System.out.println("请输入要写入文件的内容：");
            String line = scanner.nextLine();
            while (!line.equals("exit")) {
                writer.write(line + "
");
                line = scanner.nextLine();
            }

            // 关闭FileWriter和Scanner对象
            writer.close();
            scanner.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}