Question

Yeah, I know. Long title of question… So I have class name in string. I’m dynamically creating object of that class in this way:

String className = "com.package.MyClass";   
Class c = Class.forName(className);
Object obj = c.newInstance();

How I can dynamically convert that obj to MyClass object? I can’t write this way:

MyClass mobj = (MyClass)obj;

…because className can be different.

Answer 1

you don’t, declare an interface that declares the methods you would like to call:

public interface MyInterface
{
  void doStuff();
}

public class MyClass implements MyInterface
{
  public void doStuff()
  {
    System.Console.Writeln("done!");
  }
}

then you use

MyInterface mobj = (myInterface)obj;
mobj.doStuff();

If MyClassis not under your control then you can’t make it implement some interface, and the other option is to rely on reflection (see this tutorial).