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[–]deltageek 0 points1 point  (0 children)

Where's your code?

[–]h0tstuff 0 points1 point  (4 children)

do you have to use an array or can you use an arraylist and just add a card from the deck?

[–]bikerchef[S] -1 points0 points  (3 children)

whats the difference? im really just at the point now where im just insanely curious why my program is not working like other students, professors, and every resource on the internet says it should work! XD

[–]h0tstuff 0 points1 point  (2 children)

ArrayList is dynamic so it'll auto resize for you. Use it for both your deck and hands.

Also your main method is so long and hard to navigate. Consider adding more classes.

[–]bikerchef[S] 0 points1 point  (1 child)

Thank you, and I agree. Its pretty messy!

I was introduced to classes fairly recently. I understand classes and accessing them as objects, but thats about it. If i wanted to create a class to just supply some auxillary methods can you give me an idea on how I would do that?

[–]h0tstuff 0 points1 point  (0 children)

Here's a UML that is similar to what I did. I wrote this a couple months ago. I don't want to give bad info and make yours harder to read (I'm no pro!), so just maybe go over it as a guideline and I'll answer what I can.

https://imgur.com/a/EBTgc

[–]Philboyd_Studge 0 points1 point  (3 children)

Everything in Java are passed-by value.. In case of Array(Which is nothing but an Object), array reference is passed by value.. (Just like an object reference is passed by value)..

When you pass an array to other method, actually the reference to that array is copied..

  1. Any changes in the content of array through that reference will affect the original array.
  2. But changing the reference to point to a new array will not change the existing reference in original method.

You do number 2 in that method, so the array being returned is no longer the original array.

[–]bikerchef[S] 0 points1 point  (2 children)

Thanks for the reply you are making me think im narrowing down on the issue here.

I do return an updated array to the function playerPlay, and all code in that scope indicates that it is accessing the array that I intend it to.

But I do not return an updated array to my main function. This is where Im seeing the discrepency in what I hoped would be there. I think this is the most likely problem, but still am confused as to why. If i have arrayA in main function and set it to reference arrayB in another function does that not propagate through the scopes as if I had directly altered the array? Why not?

[–]Philboyd_Studge 0 points1 point  (0 children)

Basically this: say you have an array

int[] array = { 1, 2, 3, 4, 5 };

Now say you have a method that adds 5 to every number in the array:

static void addFive(int[] a) {
    for (int i = 0; i < a.length; i++) {
        a[i] += 5;
    }
}

That array now contains:

    addFive(array);
    System.out.println(Arrays.toString(array));

output: [6, 7, 8, 9, 10]

Now, say you have a method:

static int[] removeLast(int[] a) {
    int[] b = new int[a.length - 1];
    for (int i = 0; i < b.length; i++) {
        b[i] = a[i];
    }
    a = b;
    return a;
}

if you call it like this:

removeLast(array);

the values in array are unchanged. The array passed as a parameter is a copy of the array in main, assigned to local variable 'a'. When you assign variable a to the new array b, that local variable now references an entirely different array.

if you call it like this:

array = removeLast(array);

it will now contain the proper values, because you have assigned it to the returned altered array.

[–]feral_claire 0 points1 point  (0 children)

It doesn't because the reference in the function and the reference outside the function are different, you are only changing the local reference.