Question

There are three classes. One of them is parent class, and others are subclasses. For example:

Parent Class: Parent

Subclasses: SubClass1, SubClass2

My question is that how can I convert SubClass1 object into SubClass2 object without typecasting exception ?

Answer 1

You can’t, unless you create an is-a relationship between them. Sibling type instances cannot be cast to eachother.

You will have to do something like:

SubClass2 extends Parent
SubClass1 extends Subclass2

Now both inherit from Parent and you can write

Subclass2 obj = new Subclass1();

Or do the reverse.