Question

Consider the follwing code:

class Box {
    int size;

    Box(int s) { 
        size = s; 
    }
}

public class Laser {
    public static void main(String[] args) {
        Box b1 = new Box(5);
        Box[] ba = go(b1, new Box(6));
        ba[0] = b1;
        for (Box b : ba) {
            System.out.print(b.size + " ");
        }
    }

    static Box[] go(Box b1, Box b2) {
        b1.size = 4;
        Box[] ma = {b2, b1};
        return ma;
    }
}

What is the result?
i solved it to be 5 4 but it’s not the right one, the right answer is 4 4, how that come?

Answer 1

The go method changes the size of your b1 box to 4, and places it at index 1 in the array. Then the main method also sets it at index 0. So the array contains two references to b1, whose size is 4.