Why can't I add an object to this array?

Question

public class GroceryList {
    //variables
    private int count;
    private Item list[];
    public final int MAX = 30;

    //default
    public GroceryList(){
        Item placeholder1 = new Item();
        Item placeholder2 = new Item();
        list[0] = placeholder1;
        this.count = 0;
    }
}

I want to assign the Object placeholder1 to list[0] but I get a NullPointerException.

Does this answer your question? [What is a NullPointerException, and how do I fix it?](https://stackoverflow.com/questions/218384/what-is-a-nullpointerexception-and-how-do-i-fix-it) — null_awe, Dec 05 '20 at 02:32
Until you assign a value to the array, it doesn't yet exist. It's like having a parking spot -- it's just a spot that fits a car, until you park a car there. You can't tell someone to sit in the driver's seat before there's a car. — Roddy of the Frozen Peas, Dec 05 '20 at 02:35

score 2 · Answer 1 · answered Dec 05 '20 at 02:33

2

You need to initialize the array; otherwise, it is null.

public final int MAX = 30;
private Item[] list = new Item[MAX];

answered Dec 05 '20 at 02:33

Unmitigated

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THANK YOU! i can't believe I didn't think of doing that – Trevor Bollinger Dec 05 '20 at 02:34
@TrevorBollinger No problem. – Unmitigated Dec 05 '20 at 02:34
@TrevorBollinger Would you mind [accepting](https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work) my answer if it solved your issue? – Unmitigated Dec 05 '20 at 03:03

Why can't I add an object to this array?

1 Answers1