Trying to pass an array to a different class in Java

Question

I'm creating a lottery program and trying linked lists for the first time. I'm passing the numbers array from the Player class to the Lottery class so that I can display the current players Numbers, but it keeps giving me the error "actual and formal parameters differ in length".

There will be another class which will be made for the winning numbers but I'm trying to fix this issue first. I'm unsure how to fix this as I've been stuck for quite a while now.

Any help would be much appreciated.

This is the piece of code I'm having trouble with, this is in the Lottery class in the displayPlayers() method -

for(int i = 0; i < 6; i++) {
            System.out.println(currentPlayer.getNumbers(i));
        }

public class LOTTERY
{
    Scanner keyboard = new Scanner(System.in);

    private PLAYER pHead;



    public LOTTERY()
    {
        pHead = null;


    }


    public void displayPlayers() {
        PLAYER currentPlayer = pHead;
        System.out.println("Name: " + currentPlayer.getName());
        System.out.println("Age: " + currentPlayer.getAge());
        currentPlayer.randNum();
        System.out.println("Your Numbers: ");

        for(int i = 0; i < 6; i++) {
            System.out.println(currentPlayer.getNumbers(i));
        }
        menu();
    }

    public void runProg() {

        displayPlayers();
    }

    public static void main(String[] args) {
        LOTTERY lottery = new LOTTERY();
        lottery.runProg();
    }
}

Your `PLAYER` `getNumbers()` method takes no arguments. Not sure why you are trying to pass some variable `i` into that method. edit: I guess you meant to do `getNumbers()[i]` instead. `getNumbers()` returns an array, so you can access its elements just like any other array — OH GOD SPIDERS, Feb 18 '20 at 15:50
Please check out [Java Style Guide](https://www.oracle.com/technetwork/java/codeconventions-150003.pdf). In particular, the naming conventions on page 16. — WJS, Feb 18 '20 at 16:01
Does this answer your question? [Is Java "pass-by-reference" or "pass-by-value"?](https://stackoverflow.com/questions/40480/is-java-pass-by-reference-or-pass-by-value) — Henry Henrinson, Feb 18 '20 at 23:27

score 0 · Accepted Answer · answered Feb 18 '20 at 15:54

The method getNumbers() does not take an parameters but you are trying to pass it i. Additionally, this method returns an array, so you want to get this before the loop iteration, then iterate through it.

You can do this easily using an enhanced for loop:

for (int currentNum : currentPlayer.getNumbers()) {
    System.out.println(currentNum);
}

Or with a standard for loop:

int [] arr = currentPlayer.getNumbers();
for (int i = 0; i < arr.length; i++) {
     System.out.println(arr[i]);
}

score 0 · Answer 2 · answered Feb 18 '20 at 15:56

0

The error you are getting says it all, the method you wrote takes no parameters. When you call your getNumbers() method, you pass it the value of i, though java does not expect that, since you declared the method without any parameters.

answered Feb 18 '20 at 15:56

FrankK

482
8
23

Trying to pass an array to a different class in Java

2 Answers2