“线程中的异常”;“主要”;java.util.NoSuchElementException:未找到任何行
它应该从一个名为carlist.txt的文件中读取两辆车的数据,然后以正确的格式打印两辆车的数据“线程中的异常”;“主要”;java.util.NoSuchElementException:未找到任何行,java,exception,line,element,main,Java,Exception,Line,Element,Main,它应该从一个名为carlist.txt的文件中读取两辆车的数据,然后以正确的格式打印两辆车的数据 carlist.txt是一个包含以下内容的文本文件: import java.io.File; import java.io.FileNotFoundException; import java.util.*; public class CarReader2 { String name, speed, acc; public CarReader2(String carName,
carlist.txt
是一个包含以下内容的文本文件:
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();
}
}
}
程序应该打印出来
jonathan 3 7
dio 8 2
该程序已编译,但运行不正确,并在最顶端显示我发布的错误。您使用的nextLine方法错误。名称、速度和加速度在同一行中,但您使用3种下一行方法来读取它们。当您试图从一个只有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()
你读的行太多了。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:
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
或者你可以读一行,把你想要的信息分出来。我不知道这么简单,非常感谢!
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
jonathan
3
7
dio
8
2