线程 "main" java.util.NoSuchElementException 中的异常：找不到行

Question

details:
Exception in thread "main" java.util.NoSuchElementException: No line found
at java.util.Scanner.nextLine<Scanner.java:1540>
at CarReader2.main<CarReader2.java:30>
that's the entirety of the error.

我的代码：

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

public class CarReader2 {
    String name, speed, acc;

    public CarReader2(String carName, String carSpeed, String carAcc){
    name = carName;
    speed = carSpeed;
    acc = carAcc;
    }

    public String toString(){
    return "Name of car: " +name+ "\nSpeed of car: " +speed+"\nAcceleration of car: " +acc+"\n";
    }

    public static void main(String[] args) {

    File file = new File("carlist.txt");

    try {

        Scanner sc = new Scanner(file);

        while (sc.hasNextLine()) {

            String c1Name = sc.nextLine();
            String c1Speed = sc.nextLine();
            String c1Acc = sc.nextLine();
            CarReader2 car1 = new CarReader2(c1Name,c1Speed,c1Acc);
            car1.speed = c1Speed;
            car1.acc = c1Acc;

            String c2Name = sc.nextLine();
            String c2Speed = sc.nextLine();
            String c2Acc = sc.nextLine();
            CarReader2 car2 = new CarReader2(c2Name,c1Speed,c1Acc);
            car2.speed = c2Speed;
            car2.acc = c2Acc;

            System.out.println("Information on both cars");
            System.out.println("First car:");
            System.out.println(car1.toString());
            System.out.println("Second car:");
            System.out.println(car2.toString());
        }
        sc.close();
    } 
    catch (FileNotFoundException e) {
        e.printStackTrace();



    }
    }
}

它应该从名为 carlist.txt 的文件中读取 2 辆汽车的数据，然后以正确的格式打印两辆汽车的数据。

carlist.txt 是一个文本文件，包含：

jonathan 3 7
dio 8 2

程序应该打印出来，

Information on both cars
First car:
Name of car: jonathan
Speed of car: 3
Acceleration of car: 7

Second car:
Name of car: dio
Speed of car: 8
Acceleration of car: 2

该程序编译但未运行正确并显示我在最顶部发布的错误。

Answer 1

您使用的 nextLine 方法有误。名称、速度和加速度在同一行，但您正在使用 3 个 nextLine 方法来读取它们。当您尝试从一个只有 2 行的文件中读取 6 行时，就会发生这种情况。使用 sc.next() 而不是 sc.nextLine().

Answer 2

您阅读的行数过多。您的文件中只有两行，但您正在尝试读取 6。您可以将文本文件更改为：

jonathan 
3 
7
dio 
8 
2

或者你可以阅读一行并拆分出你想要的信息。

线程 "main" java.util.NoSuchElementException 中的异常：找不到行

Exception in thread "main" java.util.NoSuchElementException: No line found

java

main

element

exception

line