Re: Class<T> question

On Dec 5, 2007, at 9:48 AM, Attila Szegedi wrote:

> In my recent wrestling with "genericizing" a codebase that was
> originally pre-Java 5, I'd suggest you try replacing "Class" with
> "Class<?>".
>
> Alternatively, disable compiler warning for generics. No, seriously.
> Honestly, my feeling is that programming with generics causes more
> noise in source code than it eliminates. Yeah, it eliminates casts,
> but previously I would write:
>
> Map map = new HashMap();
> ...
> String x = (String)map.get(blah);
>
> Now I write monstrosities such as:
>
> Map<? extends Object, String> map = new HashMap<Object, String>();
> ...
> String x = map.get(blah);
>
> So, I need to write one cast less, and four type specifiers more. Net
> loss in code conciseness.
> I guess I'm just getting old and resistant to change.

Java generic syntax is notoriously verbose. Neil Gafter recently
offered a couple of proposals for a more concise syntax:

http://gafter.blogspot.com/2007/07/constructor-type-inference.html

 From his proposals:

map := new HashMap<String,List<Thing>>();

Or alternatively:

Map<String,List<Thing>> map = new HashMap<>();

In the former case the assigned type is HashMap, which prevents
programming to interfaces. It also introduces a new operator.

The second case simply relies upon inference of the proper generic
types.

-= James

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