Question

I realize that if I pass an object as a parameter of a function and do changes to it, the changes “stay” with the object. But it is not the case for an integer.

public void start() {
    int x = 100;
    modify(x);
    // I would like x to be 200 now. But it isn't :(
}

public void modify(int y) {
    y *= 2;
}

So basically, is there a way to achieve what I wanted in the code above? Is it possible to modify an integer like that (like an object reference)?

Answer 1

While working with primitives there is no concept of “reference“. But you may achieve what you want by doing something like below:

x = modify(x); may be code want.

Now x contains the results of modify(x) method invocation.