Re: Can this callback mechanism be generified?

Mark Space wrote:
> I agree this part is easier to read, I just don't see the rest of the 
> code much improved (pulling the type by name from the interface name was

> a pretty good trick.  With luck, we'll get reifiable types in Java 7 and

> then nonsense like that will be unneeded.)

I did some reading (Java Generics and Collections) and it turns out 
there are ways to get to the types, in spite of erasure. So now I do it 
a bit cleaner, no pulling apart a string and no reflection required:

private <T> Class extractGenericType(Callback<T> callback)
{
     Type[] interfaces = callback.getClass().getGenericInterfaces();

     if(interfaces.length != 1 || !(interfaces[0] instanceof 
ParameterizedType))
         throw new RuntimeException("You must supply a generified 
Callback with a single parameterized type");

     Type[] parmTypes = 
((ParameterizedType)interfaces[0]).getActualTypeArguments();

     return (Class)parmTypes[0];
}

> I might be off base here, I haven't had a need to play around with 
> generic beyond basic functions, so please take this as discussion, not 
> dogma.

Of course. :) Thanks a lot for the feedback!