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Re: Instantiation of a class

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On 7/11/2011 10:02 PM, Patricia Shanahan wrote:
> On 7/11/2011 6:57 PM, Eric Sosman wrote:
>> On 7/11/2011 7:03 PM, Fred wrote:
>>>
>>> I'm thinking about statements like String foo = new String("foo");
>>> When is the constructor specified not the name of the type of
>>> reference variable?
>>
>> Aside: The example is sort of silly, because one seldom needs
>> two instances of the same String.
>>
>> At the risk of answering a homework question, I can think of
>> two situations in which `x = new Y(...)' works even though x does
>> not have type Y. First, x's type may be that of one of Y's
>> superclasses, or of an interface implemented by Y. Second, the
>> class that's instantiated might not have a name the Java source
>> code can speak.
>>
>> And maybe the gurus will think of additional possibilities.
>>
>
> Unboxing:
>
> int x = new Integer(3);

     Ah, yes: autoboxing.  Worst pimple on the face of Java; I think
I overlooked it because a natural revulsion urged me to forget it.

> Yuck!

     Double yuck -- but thanks for pointing out the misfeature.

-- 
Eric Sosman
esosman@ieee-dot-org.invalid

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Instantiation of a class Fred <albert.xtheunknown0@gmail.com> - 2011-07-11 16:03 -0700
  Re: Instantiation of a class lewbloch <lewbloch@gmail.com> - 2011-07-11 16:41 -0700
    Re: Instantiation of a class lewbloch <lewbloch@gmail.com> - 2011-07-11 16:54 -0700
  Re: Instantiation of a class Mayeul <mayeul.marguet@free.fr> - 2011-07-12 02:02 +0200
  Re: Instantiation of a class Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-11 21:57 -0400
    Re: Instantiation of a class Patricia Shanahan <pats@acm.org> - 2011-07-11 19:02 -0700
      Re: Instantiation of a class Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-11 22:10 -0400
    Re: Instantiation of a class Fred <albert.xtheunknown0@gmail.com> - 2011-07-11 20:29 -0700
      Re: Instantiation of a class lewbloch <lewbloch@gmail.com> - 2011-07-12 14:35 -0700
    Re: Instantiation of a class Gene Wirchenko <genew@ocis.net> - 2011-07-11 21:25 -0700
      Re: Instantiation of a class Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-12 07:47 -0400
        Re: Instantiation of a class lewbloch <lewbloch@gmail.com> - 2011-07-12 11:09 -0700

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