Does array changes in method?

Question

When I write like this:

public class test {

    void mainx()
    {
        int fyeah[] = {2, 3, 4};
        smth(fyeah);
        System.out.println(\"x\"+fy         


        

Answer 1

Ok. An int in java ( and really all languages that have strict data typing ) is a primitive data type. Its just a single variable of that data type. In java this means its passed by value to the method. So when you pass in the argument, a copy of the passed variable is created. Any operations that take place in the method act on that copy not the passed variable.

Actually in java EVERYTHING is passed by value but getting into the details of how that actually is true with what I am going to say next seems inadvisable.

With the array...its a collection of variables of the primitive data type int. So an entire copy of the array isn't actually made just a copy of the reference to the memory that stores the array. so yes the value of the int IN the array is changed from operations in the method.

In short methods don't change the external value of primitives (int,float,double,long,char) with the operations in the method, you have to return the resulting value of those operations to the caller if you wish to obtain it. Operations do change the value with most objects as well as with arrays of primitives. Hope that helps. Really unsure of how low level to get. Maybe someone else can clearly explain exactly why its by value. I "get" it but find it hard to help other people understand.