I need help using Java my programs compile, however they crash when I run them.

Question

I need help using Java my programs compile, however they crash when I run them. I am trying to build an array of Car objects (no more than 100) from a file, upon reaching the end of the file I need to output the attributes of each Car (Make, Model, Year) using println.

class Car
{
   private String make;
   private String model;
   private int year;
      
   //constructor for the car class with scanner object as parameter
   public Car (Scanner fileScanner)
   {
       make = fileScanner.nextLine();
       model = fileScanner.nextLine();
       year = fileScanner.nextInt();
   }
  
   public String toString()
   {
       String result = year + " " + make + " " + model;
       return result;
   }

}

CarsFromFile

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

public class test

{

   public static void main(String [] args)
   {
       System.out.println("This is a test program.");
      
       //Get filename from the user
       System.out.print("Please enter file name: ");
       Scanner sc = new Scanner(System.in);
       String fileName = sc.nextLine();
      
       Car [] car = new Car[100];
       int totalCars = 0;
      
       try
       {  
           File file = new File(fileName);
           Scanner fileScanner = new Scanner(file);
           System.out.println();
          
           //Read file until the end
           for(int i=0; fileScanner.hasNext(); i++)
           {          
               //Create a Car object using
               car [i] = new Car(fileScanner);              
              
               //Print car summary
               System.out.println(car);
               totalCars +=1;
           }
           System.out.println("Total cars in the file are: " + totalCars);
       }
       catch (FileNotFoundException ex)
       {
           System.out.println(" File " + fileName + " was not found.");
       }
      
       System.out.println();
       System.out.println("Program complete.");
   }
}

CarFile

Fiat
500
2013
Jeep
Wrangler
2004
Ford
Fusion
2012

Explanation / Answer

I have modified the program, please use the below given program:

import java.util.Scanner;
import java.io.File;
import java.io.FileNotFoundException;
class Car
{
   private String make;
   private String model;
   private String year;
    
   //constructor for the car class with scanner object as parameter
   public Car (Scanner fileScanner)
   {
       this.make = fileScanner.nextLine();
       this.model = fileScanner.nextLine();
       this.year = fileScanner.nextLine();
   }

   @Override
   public String toString()
   {
       String result = year + " " + make + " " + model;
       return result;
   }

}

public class test

{

   public static void main(String [] args)
   {
       System.out.println("This is a test program.");
    
       //Get filename from the user
       System.out.print("Please enter file name: ");
       Scanner sc = new Scanner(System.in);
       String fileName = sc.nextLine();
    
       Car [] car = new Car[100];
       int totalCars = 0;
    
       try
       {
           File file = new File(fileName);
           Scanner fileScanner = new Scanner(file);
           System.out.println();
        
           //Read file until the end
           for(int i=0;i<100; i++)
           {      
             
               //Create a Car object using
               car [i] = new Car(fileScanner);            
            
               //Print car summary
               System.out.println(car[i]);
               totalCars +=1;
            
             
           }
           System.out.println("Total cars in the file are: " + totalCars);
       }
       catch (FileNotFoundException ex)
       {
           System.out.println(" File " + fileName + " was not found.");
       }
    
       System.out.println();
       System.out.println("Program complete.");
   }
}

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