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Re: quick question

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01.03.2013 21:08, Daniele Futtorovic kirjoitti:
> On 01/03/2013 19:48, Eric Sosman allegedly wrote:
>> On 3/1/2013 1:25 PM, Doug Mika wrote:
>>> reading a book a came upon the following inside a 'myDialog extends
>>> JDialog" class inside an actionlistener implemented as an anonymous
>>> inner class.
>>>
>>> myDialog.this.dispose()
>>>
>>> why not simply write
>>>
>>> this.dispose()
>>
>>     That would be perfectly all right, if you get your thrills
>> from reading the compiler's error messages.  :)
>>
>>> does it have anything do with the fact that this line is found within
>>> an anonymous inner class that is an actionListener?
>>
>>     Yes.  An unadorned `this' would refer to the instance of the
>> class whose code is running.  That's the anonymous class that
>> implements ActionListener, a class that doesn't even *have* a
>> dispose() method (unless one's been added explicitly in the
>> anonymous class, which would be awfully strange).
>>
>>     Writing `this.dispose()' or simply `dispose()' would try
>> to call the anonymous class' dispose() method, not any method
>> belonging to the enclosing myDialog (poor choice of name, BTW).
>> The intent, most likely, is to close the dialog -- so the code
>> uses `myDialog.this' to mean "Not *this* `this', but the `this'
>> of the enclosing class named `myDialog'."  It's that enclosing
>> class' dispose() that's being called.
>>
> 
> For the record, it's called a "Qualified 'this'", and the specification
> can be found here:
> <http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.8.4>
> 

This "Qualified this" is kind of hard to understand. How

    myDialog.this.dispose()

differs from

    myDialog.dispose()

If myDialog is an object instance, would't it be sufficient just call
dispose it?



-- 

"Unfortunately suspend does mean things sometimes"

Husse Apr 25 2007

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quick question Doug Mika <dougmmika@gmail.com> - 2013-03-01 10:25 -0800
  Re: quick question Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-03-01 13:48 -0500
    Re: quick question Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2013-03-01 20:08 +0100
      Re: quick question Donkey Hottie <donkey@fredriksson.dy.fi> - 2013-03-01 22:52 +0200
        Re: quick question Joerg Meier <joergmmeier@arcor.de> - 2013-03-01 22:22 +0100
          Re: quick question Lew <lewbloch@gmail.com> - 2013-03-01 15:31 -0800
  Re: quick question Arne Vajhøj <arne@vajhoej.dk> - 2013-03-01 18:30 -0500
  Re: quick question Roedy Green <see_website@mindprod.com.invalid> - 2013-03-01 15:38 -0800

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