How to acces normal methods of abstract class in dervied class with overriding property

How to acces normal methods of abstract class in dervied class with
overriding property

class Parent {
int i = 9;
public void display() {
System.out.println("base");
}
}
class Child extends Parent {
int i = 8;
public void display() {
System.out.println("derived");
}
}
public class A extends Child {
int i = 4;
public static void main(String args[]) {
Parent a1 = new Child();
//added
System.out.println(a1.i);
a1.display();
}
}