What means addOneTo?

Question

In the Value Types, addOneTo is (perhaps) a method. If addOneTo means you add 1 at integer "num", why the integer is remains 5? (The integer is 5)
https://www.sololearn.com/discuss/68786/?ref=app
https://www.sololearn.com/discuss/784112/?ref=app

Answer 1

In Java, variables are passed to functions by value and not by reference. So by doing

static void addOneTo(int num) {
num = num + 1;
}

and then calling the function:

int num = 1;
addOneTo(num);

The value of x is incremented by 1 only within the scope of the function. The variable "num" which is outside the scope of addOneTo still remains as 1, unchanged.