Question

I’m getting confused at how java works with everything being a class.

I make a class foo.java and in the main method of foo.java I make an instance of foo (a class creating itself makes no sense to me but it seems normal in java ?)

Then I make a instance of another class bar, so I now have instances of foo and bar inside the foo class but how do I access the member variables of foo with the functions in bar?

foo is the processing code and bar is the ui and needs to see all the data in foo so it can display it.

Answer 1

There are a lot of possibilities. One is to construct foo with a bar instance:

public class Foo {
    public void someFooMethod() {
    }
    public static void main(String[] args) {
        Foo foo = new Foo();
        Bar bar = new Bar(foo);
        bar.someBarMethod();
    }
}

public class Bar {
    private Foo fooLocalRefence;
    public Bar(Foo foo) {
        this.fooLocalReference = foo;
    }
    public someBarMethod() {
        this.fooLocalReference.someFooMethod();
    }
}