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Java using scanner for user input to set size of array

I want to allow for the user to be able to choose the size of the int array in my program

Right now I have the following code:

public class SortTests {
    private static int size;
    private static int [] myArray = new int [size]; 

    public static void setArraySize() {
        Scanner scan = new Scanner(System.in);
        System.out.println("Enter a whole number to specify the size of the array: ");
        size = scan.nextInt();
        
    }
    
    public static void fillArray() {
        Random randNum = new Random();
        for (int i = 0; i < myArray.length; i++) {
            myArray[i] = randNum.nextInt(100);
        }
    }

I’m not sure why but when I go to test and print my Array.toString it simply prints ”'[]”’ (obviously it is not doing what it should be doing and populating the int array).

Does anyone have any suggestions on how I can tidy my code smell up and make it so this actually works?

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Answer

You have created the array already, and your setArraySize changes the size variable only.

public class SortTests {
    private static int size; <-- setArraySize affects this.
    private static int [] myArray = new int [size];  <-- setArraySize does not affect this.  Size was defaulted to 0, so myArray will always be a 0-sized array.

Change to something similar to this:

public class SortTests {
    private static int [] myArray = new int [size]; 

    public static void setArraySize() {
        Scanner scan = new Scanner(System.in);
        System.out.println("Enter a whole number to specify the size of the array: ");
        int size = scan.nextInt();
        myArray = Arrays.copyOf(myArray, size);
    }
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