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Re: limitations on using enum as generic parameter

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From	Daniele Futtorovic <da.futt.news@laposte.net.invalid>
Newsgroups	comp.lang.java.programmer
Subject	Re: limitations on using enum as generic parameter
Date	Tue, 08 Feb 2011 20:47:31 +0100
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On 08/02/2011 20:40, Ken Wesson allegedly wrote:
> On Tue, 08 Feb 2011 20:33:37 +0100, Daniele Futtorovic wrote:
>
>> On 08/02/2011 19:46, Ken Wesson allegedly wrote:
>>> That's not going to work. It's a static method of a class that isn't
>>> determined at this point in the code, so the compiler simply has no
>>> clue what to call. Hence the error message.
>>>
>>> If you really need to do something like this, you'll need to use
>>> reflection on a class object.
>>
>> For the record: no. See my and ninja markspace's replies.
>
> I meant the general case of wanting to invoke a static method on a type
> parameter, where the method depends on the run-time type (so, it's not a
> method of X where you have<E extends X>, but a method implemented
> differently for each choice of E).

I would argue that this would be bad design. Aside from cases where 
reflection is part of the contract (Spring, for instance), it should 
only be used exceptionally, if at all.

> In the special case of an enum there's getEnumConstants.

Which doesn't work via reflection, FWIW.

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Re: limitations on using enum as generic parameter Daniele Futtorovic <da.futt.news@laposte.net.invalid> - 2011-02-08 20:33 +0100
  Re: limitations on using enum as generic parameter Lew <lew@lewscanon.com> - 2011-02-09 10:07 -0800
  Re: limitations on using enum as generic parameter Daniele Futtorovic <da.futt.news@laposte.net.invalid> - 2011-02-08 23:44 +0100
  Re: limitations on using enum as generic parameter Daniele Futtorovic <da.futt.news@laposte.net.invalid> - 2011-02-08 20:47 +0100
    Re: limitations on using enum as generic parameter Lew <lew@lewscanon.com> - 2011-02-08 12:31 -0800
  Re: limitations on using enum as generic parameter Ken Wesson <kwesson@gmail.com> - 2011-02-08 20:40 +0100

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