how can I create an instance with a reference to an object that was created at the beginning of the program?

Question

Class A {

Class B {

// how to reference Object A?
}

public static void main() {

A a = new A();
a.method();

}

}

Answer 1

public class A {
public static int i = 30;
public class B { int j = 4;
public class C { int k = i;
}
}
}

Objects:
A a = new A();
A.B b = a.new B();
A.B.C c = b.new C();