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Groups > comp.lang.java.help > #849

Re: Instantiation of a class

Date 2011-07-11 19:02 -0700
From Patricia Shanahan <pats@acm.org>
Newsgroups comp.lang.java.help
Subject Re: Instantiation of a class
References <d98a873f-d5db-4243-be26-2109c25744b2@q12g2000prb.googlegroups.com> <ivg9md$c1c$1@dont-email.me>
Message-ID <lcadnRwToZK_NobTnZ2dnUVZ_oudnZ2d@earthlink.com> (permalink)

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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);

Yuck!

Patricia

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Thread

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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