类之间的二维数组| 爪哇

Question

i have one problem with inheritance. I have 2 classes, (CreateAnArray,TheGame) and now - i have two-dimensional array which is created in 'CreateAnArray' class and i want to use it in 'TheGame' class, but every time i try to do it, it shows me 'null'.

public class TheGame extends CreateAnArray{

public void insert(String k){
    for(int i=0;i<arrayOX.length;i++){

        for(int j=0;j<arrayOX.length;j++){
            if(arrayOX[i][j] == k && (arrayOX[i][j] != "x" && arrayOX[i][j] != "y"))
                arrayOX[i][j]=k;
            System.out.println(arrayOX[i][j]);
        }   
    }
}

And the second class:

public class CreateAnArray {
public String[][] arrayOX =  new String[3][3];

public void create(){
    int k=1;
    for(int i=0;i<arrayOX.length;i++){
        for(int j=0;j<arrayOX.length;j++){
            arrayOX[i][j]=Integer.toString(k++);
        }
    }
}

public void show(){
    for(int i=0;i<arrayOX.length;i++){
        for(int j=0;j<arrayOX.length;j++){
            System.out.print(arrayOX[i][j]);
        }
        System.out.println();
    }
}

I've tried a returning method, creating objects but nothing helps, what should I do?

Answer 1

Don't do this. Have your first class operate normally. When it needs arrayOX , have a function return that array to the first class. Don't extend the class here.

public String[] create(){
    String[] arrayOX = new String[3][3];

    int k=1;
    for(int i=0;i<arrayOX.length;i++){
        for(int j=0;j<arrayOX.length;j++){
            arrayOX[i][j]=Integer.toString(k++);
        }
    }

    return arrayOX;
}

Then, call this function to get arrayOX in the other class.