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Re: What's the difference between and instance and an object?

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On 06/06/2011 18:33, Chad wrote:
> On Jun 6, 9:18 am, Patrick<patr...@antispam.invalid>  wrote:
>> Le 06/06/2011 18:08, Chad a écrit :
>>
>>
>>
>>> How can there be an instance of MyStack when I never made a
>>> constructor for it? That is, I never create a MyStack object.
>>
>> You always have a constructor, even if implicit.
>> You created an instance with new MyStack().
>
> Maybe I'm acting like a dweeb about this, but according to the Java
> Docs, when there is no explicit constructor, then the implict
> constructor is Object. I think that is how they say it.

This is not a matter of opinion.

Here is what the Java Docs have to say:
http://java.sun.com/docs/books/jls/third_edition/html/classes.html#8.8.9

> So I figured
> that when I created instance of MyStack with 'new MyStack()', that the
> only instance would be Object since I omitted the MyStack constructor.

As you could verify with your simple test, that is incorrect.
For starters, for any symbol 'A' denoting a class, 'new A()' will always 
either:
- build an instance of the class 'A'
- throw an Exception
- refuse to compile

Same goes if this call is given parameters.

In other words, it cannot possibly build an instance of any other class, 
neither Object nor anything.

--
Mayeul

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Thread

What's the difference between and instance and an object? Chad <cdalten@gmail.com> - 2011-06-06 09:08 -0700
  Re: What's the difference between an instance and an object? Chad <cdalten@gmail.com> - 2011-06-06 09:16 -0700
  Re: What's the difference between and instance and an object? Patrick <patrick@antispam.invalid> - 2011-06-06 18:18 +0200
    Re: What's the difference between and instance and an object? Chad <cdalten@gmail.com> - 2011-06-06 09:33 -0700
      Re: What's the difference between and instance and an object? Mayeul <mayeul.marguet@free.fr> - 2011-06-06 18:54 +0200
        Re: What's the difference between and instance and an object? Chad <cdalten@gmail.com> - 2011-06-06 10:11 -0700
        Re: What's the difference between and instance and an object? Abu Yahya <abu_yahya@invalid.com> - 2011-06-08 21:21 +0530
          Re: What's the difference between and instance and an object? Abu Yahya <abu_yahya@invalid.com> - 2011-06-08 21:24 +0530
            Re: What's the difference between and instance and an object? Patricia Shanahan <pats@acm.org> - 2011-06-08 09:33 -0700
              Re: What's the difference between and instance and an object? Abu Yahya <abu_yahya@invalid.com> - 2011-06-08 22:07 +0530
          Re: What's the difference between and instance and an object? Lewis Bloch <lewisbloch@google.com> - 2011-06-10 11:06 -0700
            Re: What's the difference between and instance and an object? Abu Yahya <abu_yahya@invalid.com> - 2011-06-11 23:58 +0530
      Re: What's the difference between and instance and an object? Lewis Bloch <lewisbloch@google.com> - 2011-06-10 11:05 -0700

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