Hi, i have this code:

private static Importable getRightInstance(String s) throws Exception {
   Class<? extends Importable> c = Class.forName(s).asSubclass(Importable.class);
   Importable i = c.newInstance();
   return i;
}

which i can also write

private static Importable getRightInstance(String s) throws Exception {
   Class<? extends Importable> c = (Class<? extends Importable>)Class.forName(s);
   Importable i = c.newInstance();
   return i;
}

or

private static Importable getRightInstance(String s) throws Exception {
   Class<?> c = Class.forName(s);
   Importable i = (Importable)c.newInstance();
   return i;
}

where Importable is an interface and s is a string representing an implementing class. Well, in any case it gives the following:

Exception in thread "main" java.lang.IncompatibleClassChangeError: class C1 has
interface Importable as super class

Here is the last snippet of the stack trace:

 at java.lang.Class.forName(Class.java:169)
 at Importer.getRightImportable(Importer.java:33)
 at Importer.importAll(Importer.java:44)
 at Test.main(Test.java:16)

Now, class C1 actually implemens Importable and i totally don't understand why it complaints.

Thanks in advance.