Question

If I initialize an array in a Java method like:

final double[][] myArray = new double[r][c];

Will I be allowed to do this later in the method?

myArray[0] = new double[c];

Answer 1

I’ll provide you an example of this:

public class Main {
    public static void main(String[] args) {
        final int[] finalArray = new int[5];
        finalArray[0] = 10;
        System.out.println(finalArray[0]);
        finalArray[0] = 9001;
        System.out.println(finalArray[0]);
        finalArray = new int[5] //compile error!!!
    }
}

This is because the final modifier will say that the reference to the array (the pointer) can’t change, but the elements of the array (that could have another pointer) can change with no problem.

EDIT:

Another example with 2d array:

public class Main {
    public static void main(String[] args) {
        final int[][] array2d = new int[5][];
        for(int i = 0; i < array2d.length;i++) {
            array2d[i] = new int[6];
        }
        //the size of the rows can change with no problem.
        array2d[0] = new int[8];
    }
}