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NNTP-Posting-Date: Tue, 23 Apr 2013 10:37:17 -0500
Date: Tue, 23 Apr 2013 16:37:15 +0100
From: lipska the kat <"nospam at neversurrender dot co dot uk">
Organization: Trollbusters 3
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Subject: Re: <? extends String>
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On 23/04/13 14:55, Steven Simpson wrote:
> On 23/04/13 11:31, Donkey Hottie wrote:
>> 23.04.2013 12:48, Steven Simpson kirjoitti:
>>> public static String generateWindowsArgument(List<? extends String>
>>> args) {
>> <offtopic>java.lang.String is final, so nothing can extend it.
>> </offtopic>
>
> It's a matter of habit drawn from the general principle that if I don't
> need to modify the list, I don't impose the additional, unnecessary
> constraint on the caller, regardless of the element type.

I don't understand this. In the first place List<? extends String>  says 
nothing about your ability to modify the list, you can add and remove 
Strings to your hearts content, secondly the only type you can pass as 
argument to generateWindowsArgument is List<String> so the construct is 
redundant anyway In fact, given that >>extends String<< is effectively 
meaningless I'm surprised the compiler doesn't at least issue a warning. 
I suppose you get away with it because compile time type erasure gets 
rid of any type arguments and as there can be only one type of argument 
anyway a warning would be superfluous.

lipska

-- 
Lipska the KatŠ: Troll hunter, sandbox destroyer
and farscape dreamer of Aeryn Sun