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Re: Eclipse

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On Thu, 29 Jun 2017 12:55:26 -0700, Eric Douglas wrote:

> On Thursday, June 29, 2017 at 3:02:15 PM UTC-4, Martin Gregorie wrote:
>> Err, not really. An Interface defines a set of methods that must all be
>> defined by an Interface but is not a Class anbd I think thats what is
>> making Eclipse spit.
>> 
>> I think you need to declare the various classes that implement
>> MyCustomInterface into subclasses of an (abstract?) superclass that
>> extends JContainer which, at a quick glance, inherits the methods you
>> mention from Container and Component.
>> 
>> 
> That is the problem.  These are all Component, as the focusGained()
> refers to them, or JComponent but they're different components.  They
> are already subclasses of the various components (JTextField, JTextArea,
> JComboBox, JSpinner) so they can't subclass an abstract class so they
> have to use the interface.  The ArrayList has to refer to it's elements
> with the interface or else I'd have to declare it as
> ArrayList<JComponent> and assume we're only adding objects to it which
> implement the interface, and every time I want to call an interface
> method on an object in the array I have to cast the object.  Unless I'm
> missing something?  Like I said you can't just define both ways as
> ArrayList<JComponent implements MyCustomInterface>, I tried that.

Understood.

What does your MyCustomInterface contribute to making it easier to handle 
the different types of objects?

Would it help to do something like declaring a MyClass that extends 
Component and implements MyCustomInterface and that is passed the 
JTextField, etc as constructor argument? At least this should avoid your 
casting problem.

Apart from that all I can suggest is that, after double checking that 
your classes compile correctly when javac is run either manually of via 
ant outside the Eclipse environment, you ask the Eclipse project why this 
has started to happen in this version and/or file a bug against Eclipse.

Filing bugs is very much in the FOSS ethos - IMO you should regard the 
work involved in posting good, well documented bug reports as your 
contribution to the Eclipse project.  Put another way, users of 
commercial software pay cash: FOSS users pay by testing, reporting bugs 
and making sensible enhancement suggestions.


-- 
martin@   | Martin Gregorie
gregorie. | Essex, UK
org       |

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Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-28 07:57 -0700
  Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-28 09:04 -0700
    Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-28 12:07 -0700
      Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-29 06:05 -0700
        Re: Eclipse Jerry Stuckle <jstucklex@attglobal.net> - 2017-06-29 09:32 -0400
          Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-29 06:42 -0700
        Re: Eclipse Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-06-29 09:47 -0400
          Re: Eclipse Andreas Leitgeb <avl@logic.at> - 2017-06-30 14:47 +0000
            Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-30 08:22 -0700
              Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-07-07 06:19 -0700
                Re: Eclipse Andreas Leitgeb <avl@logic.at> - 2017-07-13 09:29 +0000
        Re: Eclipse Martin Gregorie <martin@address-in-sig.invalid> - 2017-06-29 17:18 +0000
          Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-29 11:08 -0700
            Re: Eclipse Martin Gregorie <martin@address-in-sig.invalid> - 2017-06-29 18:58 +0000
              Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-29 12:55 -0700
                Re: Eclipse Martin Gregorie <martin@address-in-sig.invalid> - 2017-06-29 21:31 +0000
                Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-30 04:55 -0700
                Re: Eclipse Martin Gregorie <martin@address-in-sig.invalid> - 2017-06-30 13:02 +0000
              Re: Eclipse Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-06-29 16:34 -0400
                Re: Eclipse Eric Douglas <e.d.programmer@gmail.com> - 2017-06-29 13:49 -0700
                Re: Eclipse Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-06-29 18:16 -0400
  Re: Eclipse Arne Vajhøj <arne@vajhoej.dk> - 2017-07-02 11:56 -0400

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