My only problem with my code is checking if a file exists. The code works with N

Question

My only problem with my code is checking if a file exists. The code works with Numbers.txt file which is in the project file but if I enter a dummy text file like Words.txt (made up), I get errors and the "The file " + inputFile + "does not exist." message does not appear like it should. Any tips by looking at my code?

This is the

import java.util.Scanner;
import java.io.*;

public class NumberAnalysis
{
//Array of numbers
final private double [] NUMBERS;
  
public NumberAnalysis(String inputFile)throws IOException
{
NUMBERS = new double[20];
File file = new File(inputFile);
Scanner input = new Scanner(file);
int i = 0;
double total, low, high, average;
  
/**
* Make sure the file exists.
*/
if(!file.exists())
{
//Display an error message.
System.out.println("The file " + inputFile + " does not exist.");
  
//Exit the program.
System.exit(0);
}
  
while(input.hasNext())
{
//Read a value from the file.
NUMBERS[i] = input.nextDouble();
i++;
}
int size = i;
total = NUMBERS[0];
low = NUMBERS[0];
high = NUMBERS[0];
i = 1;
while(i < size)
{
if(NUMBERS[i] > high)
high = NUMBERS[i];
if(NUMBERS[i] < low)
low = NUMBERS[i];
total += NUMBERS[i];
i++;
}
  
  
  
average = total / size;
//Displaying data
System.out.println("Lowest number in Array is: " + low);
System.out.println("Highest number in Array is: " + high);
System.out.println("Total number in Array is: " + total);
System.out.println("Average number in Array is: " + average);
  
//Close the file.
input.close();
}

}

Explanation / Answer

import java.util.Scanner;
import java.io.*;

public class NumberAnalysis {
   // Array of numbers
   final private double[] NUMBERS;

   public NumberAnalysis(String inputFile) throws IOException {
       NUMBERS = new double[20];
       File file = new File(inputFile);

       int i = 0;
       double total, low, high, average;

       /**
       * Make sure the file exists.
       */
       if (!file.exists()) {
           // Display an error message.
           System.out.println("The file " + inputFile + " does not exist.");

           // Exit the program.
           System.exit(0);
       }
       Scanner input = new Scanner(file);
       while (input.hasNext()) {
           // Read a value from the file.
           NUMBERS[i] = input.nextDouble();
           i++;
       }
       int size = i;
       total = NUMBERS[0];
       low = NUMBERS[0];
       high = NUMBERS[0];
       i = 1;
       while (i < size) {
           if (NUMBERS[i] > high)
               high = NUMBERS[i];
           if (NUMBERS[i] < low)
               low = NUMBERS[i];
           total += NUMBERS[i];
           i++;
       }

       average = total / size;
       // Displaying data
       System.out.println("Lowest number in Array is: " + low);
       System.out.println("Highest number in Array is: " + high);
       System.out.println("Total number in Array is: " + total);
       System.out.println("Average number in Array is: " + average);

       // Close the file.
       input.close();
   }
   public static void main(String[] args) {
       try {
              
           new NumberAnalysis("Numbers.txt");  
           new NumberAnalysis("Words.txt");
       } catch (Exception e) {
           // TODO: handle exception
           e.printStackTrace();
       }
      
      
   }
}
OUTPUT:
Lowest number in Array is: 35.0
Highest number in Array is: 85.0
Total number in Array is: 1260.0
Average number in Array is: 63.0

The file Words.txt does not exist.

Note :
Change the place of Scanner input = new Scanner(file);
just after checking the file exits or not

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