Re: Can this callback mechanism be generified?

From:
Mark Space <markspace@sbc.global.net>
Newsgroups:
comp.lang.java.help
Date:
Sat, 03 May 2008 23:27:15 GMT
Message-ID:
<nx6Tj.8250$LQ4.2721@newssvr11.news.prodigy.net>
Casper Bang wrote:

...to the final version, where the type of my callback is extracted
rather than having to be supplied explicitly:

installCallback( new Callback<Date>(){
        public String format(Date date) {
            return SimpleDateFormat.getInstance().format(date);
        }
    });


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 guess I don't see the advantage of Class<?> over just Class, when
you're going to cast it yourself anyway. Given the nature of the
problem, the second form seems more clear and correct -- it says "I'm
not using generics, I'm tracking the type of Class myself." Class<?>
implies to me that you can't and won't resolve the type of Class<C> further.

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.

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