Thread: FileScan and Scanner issue! HELP

So, I keep getting a java.util.InputMismatchException null(in java.util.Scanner). I have used the same logic in a different program with a list of integers. This program takes from a list of numbers from 1-2000. I've made sure that "integers.txt" is an actual text file in the project. I am using BlueJ to code this. Can anyone shed some light on this?

import java.util.Scanner;
import java.io.*;
 
public class Sorting
{
    private static int[] a = new int[2000];
    private int v;
    private Scanner fileScan, dataScan;
    private static String oneLine;
    public Sorting() throws IOException
    {
        int place = 0;
        fileScan = new Scanner(new File("integers.txt"));
        while(fileScan.hasNext())
        {    
            oneLine = fileScan.nextLine();
            dataScan = new Scanner(oneLine);
            v = dataScan.nextInt(); //it errors here
 
            a[place] = v;
            place++;
        }
    }
 
    public static void main(String args[]) throws IOException
    {
        Sorting s = new Sorting();
        BubbleSort bubble = new BubbleSort();
        InsertionSort insert = new InsertionSort();
        SelectionSort select = new SelectionSort();
 
        bubble.sort(a);
        insert.sort(a);
        select.sort(a);
 
        System.out.println("Bubble Sort had " + bubble.getCompare() 
            + " comparisons and " + bubble.getExchange() + " exchanges.");
 
        System.out.println("Insertion Sort had " + insert.getCompare() 
            +" comparisons and " + insert.getExchange() + " exchanges.");
 
        System.out.println("Selection Sort had " + select.getCompare() 
            +" comparisons and " + select.getExchange() + " exchanges.");
    }
}

Add a println() to the code to print out the value of the line read from the file so you can see what the Scanner method is trying to read with nextInt().

printlns are useful for seeing what the computer is seeing.