Member Avatar for alkeshtech

Hi guys,
I am writing a method which given an instance of a class and a type (as a string), it will return an instance of the named type constructed from the instance if possible, null otherwise.
So say,

class A{
      A(B b) {
        ..
      }
      ..
}
class B {
      B(C c) {
        //
      }
      // …
}

class C {
      // ..
}

so method, conversion(new C(), "A"), should return A as conversion from C->A exists. Any ideas?

Edited by Nick Evan because: Fixed formatting
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Member Avatar for masijade

There is no "conversion" involved. It is a simple cast, and after the return the instance will still be the same type it was before. And, it's not possible to "dynamically" change the return type of a method anyway, so the entire is doomed to failure. Maybe if you would explain what it is you are actually trying to accomplish we could help you.

Member Avatar for alkeshtech

Well, method returns A as an instance if coversion is possible using Java's reflection. This is the question our teacher gave us to think about. So, I am guessing we may see it on the quiz or exam.

Member Avatar for javaAddict 
public static Object convesrion(Object obj, String s) {

}

If you search the API for reflect and look at the Class class, I think that you can find methods that:
Using a String create a Class instance of the given type.
Methods that check if something can be cast.

Also as String argument be careful to add the package as well: Class.forName("pack.A");

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