Re: Generics and forName()


On Tue, 31 Jan 2006 09:35:32 +0100, Jacob <jacob@xxxxxxxxx> wrote,
quoted or indirectly quoted someone who said :

>The following gives an unchecked warning in the first line due to the
>forced cast. Using "?" just postpone the the problem:
>
> Class<A> clazz = (Class<A>) Class.forName("A");
> Constructor<A> ctor = clazz.getConstructor(String.class);
> A a = ctor.newInstance("hello world");

Unchecked means the compiler cannot guarantee safety at compile time.
The truth is it can't. It has absolutely no idea what A will be/do. If
you want the compiler to be able to check, it wants to see the code at
compile time.

Further this code makes no sense to me. If type A is known at compile
time, why are you dicking around with Class.forName. You only do that
when you DON'T know the class name, just an interface it implements..
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