How to set a new value for a public int in java

Question

In the java programming language, how do you set a new value for a public integer, so that an outside method in an outside class can get this value, by simply calling the variable name. I have example code:

    package build;

    public class Main {

        public static void main(String[] args) {
            Main main = new Main();
            main.init();
        }

        public int myVar = 1;

EDIT:

More specific question: How can I get the variable's updated value, not it's starting value without passing it on to a the method?

        public void init() {
            Retrieve ret = new Retrieve();
            int i = 0;
            for(int n = 1; n > 0; ++n) {
                myVar = myVar + 1;
                System.out.println("Value: " + myVar);
                i = ret.init();
                System.out.println("Retrieved Value: " + i);
            }
        }

        int getValue()  {
            int b = myVar;
            return b;
        }
    }

and for Return:

    package build;

    public class Retrieve {

        public int init() {
            Main main = new Main();
            int a = 1;
            a = main.getValue();
            return a;
        }
    }

In the example above, how would I set the variable "myVar" to a value other than one, so that when I call the 'init' method in the 'return' class, it returns that new value, rather than 1, the starting value?

Answer 1

There's something very wrong with your object relationship.

The main problem is in Retrieve.init()

public int init() {
        Main main = new Main();
        int a = 1;
        a = main.getValue();

Every time you call init() you are making a new instance of main, so main.myVar will be 1. I assume you wanted to call the value of the first main.

public class Retrieve {

    public int init(Main main) {            
        int a = 1;
        a = main.getValue();
        return a;
    }
}

and in Main.init change

Retrieve ret = new Retrieve();

to

Retrieve ret = new Retrieve(this);

Answer 2

It's fairly awful OOP , but this will work:

public class Retrieve {

    public int init() {
        Main main = new Main();
        int a = 1;
        main.myVar = 42;
        a = main.getValue();
        return a; // returns 42
    }
}