Java: How to fix 'FileNotFoundException' in this case?

Question

This is my code:

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

 public class ArrayAnalyser {
     
     public static void main(String[] args) throws IOException {
         int size;
         double[] array;

         String fileName = "C:\\Users\\kengock\\Desktop\\Numbers.txt";
         size = getLineNumber(fileName);
         array = new double[size];
         File file = new File(fileName);
         Scanner infile = new Scanner(file);
         int index = 0;
         
         while (infile.hasNext()) {
             array[index] = infile.nextDouble();
             index++;

         }
         
         infile.close();
         System.out.println("The min is " + getSmallest(array));
         System.out.println("The average is " + getAverage(array));
     }

     public static int getLineNumber(String fileName) throws IOException {
         int size = 0;
         File file = new File(fileName);
         Scanner infile = new Scanner(file);
         
         while (infile.hasNext()) {
             size++;
             infile.nextLine();

         }
         
         infile.close();
         return size;
     }
     
     public static double getSmallest(double[] array) {
         double min = array[0];
         for (int i = 0; i < array.length; i++) {
             if (array[i] < min)
                 min = array[i];

         }
         return min;
     }

     public static double getAverage(double[] array) {
         double sum = 0;
         for (int i = 0; i < array.length; i++) {
             sum += (array[i]);

         }
         return sum / array.length;
     }
 }

This is the error message I'm getting:

C:\\Users\\kengock\\Desktop>java ArrayAnalyser Exception in thread "main" java.io.FileNotFoundException: C:\\Users\\kengock\\Desktop (存取被拒。) at java.base/java.io.FileInputStream.open0(Native Method) at java.base/java.io.FileInputStream.open(FileInputStream.java:212) at java.base/java.io.FileInputStream.(FileInputStream.java:154) at java.base/java.util.Scanner.(Scanner.java:639) at ArrayAnalyser.getLineNumber(ArrayAnalyser.java:33) at ArrayAnalyser.main(ArrayAnalyser.java:13)

What should I do with the file path?

Answer 1

In the below line of code you have only mentioned the path of the file but not the name like abc.txt

String fileName="C:\\Users\\kengock\\Desktop";

It should be like :-

 String fileName="C:\\Users\\kengock\\Desktop\\abc.txt";

Answer 2

public class ArrayAnalyser {

    public static void main(String[] args) throws IOException {
        File file = new File("c:/Users/kengock/Desktop/Numbers.txt");
        double[] arr = readArrayFromFile(file);
        System.out.println(Arrays.toString(arr));
        System.out.format(Locale.ENGLISH, "The min is %.2f\n", getSmallest(arr));
        System.out.format(Locale.ENGLISH, "The average is %.2f\n", getAverage(arr));
    }

    public static double[] readArrayFromFile(File file) throws FileNotFoundException {
        List<Double> numbers = new ArrayList<>();

        try (Scanner scan = new Scanner(file)) {
            scan.useLocale(Locale.ENGLISH);

            while (scan.hasNext())
                numbers.add(scan.nextDouble());
        }

        return numbers.stream().mapToDouble(i -> i).toArray();
    }

    public static double getSmallest(double[] arr) {
        return Arrays.stream(arr).min().orElse(0);
    }

    public static double getAverage(double[] arr) {
        return Arrays.stream(arr).average().orElse(0);
    }
}