Re: Method calling

From:

Tom Anderson <twic@urchin.earth.li>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 30 Jul 2008 00:29:41 +0100

Message-ID:

<Pine.LNX.4.64.0807300026260.16575@urchin.earth.li>

On Tue, 29 Jul 2008, gaijinco wrote:

Thanks Steve and Seamus for your quick responses.

I checked the API and I got a prototype running very quickly.

There's only just I question remaining: In the API Class is not a raw
type, it's parametized. However if I try to do this:

TestClass t = new TestClass();
Class<TestClass> c = t.getClass();

Eclipse's compiler complains:

Type mismatch: cannot convert from Class<capture#1-of ? extends
TestClass> to Class<TestClass>

What's the deal with that?

It's because when you have a variable of type TestClass, it could contain
an instance of TestClass, or of a subclass of TestClass. So, your Class
could be a Class<TestClass>, or it could be a Class<a subclass of
TestClass> - and in formal generics language, that's Class<? extends
TestClass>.

To get an exact Class, do it statically, with a class literal:

Class<TestClass> cl = TestClass.class ;

You could do this, though:

Class<? extends TestClass> cl = t.getClass() ;

You can do pretty much the same things with a Class<? extends TestClass>
as a Class<TestClass>. More or less. Probably.

tom

--
DO NOT WANT!