Question

Let’s say we have 2 classes A and B

public class A{

    private int member1;

    A() {
        member1 = 10;
    }

    public getMember(){
        return member1;
    }

}

Class B is also on the same lines except that its member variable is named member2 and gets intitialized to say 20 inside the constructor.

My Requirement :

At runtime , I get a string which contains a className ( could be A or B). I want to dynamically create an object of this class along with invoking the constructor. How can I achieve this . I don’t want to use interfaces for common functionality of above classes Morever, later on I set the properties of this raw object using Propery Builder Bean Util class based on a list of columns .

Class clazz = Class.forName("className");
Obj obj = clazz.newInstance();

How I can dynamically convert that obj to className object.

Answer 1

How can I achieve this . I don’t want to use interfaces for common functionality of above classes

Then the answer is very simple and you won’t like it: you can’t. You want to modify the static type of the variables which is, by definition, determined at compile time. Changing it at runtime is not possible.