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From Gale Naylor <Ga...@noventussolutions.com>
Subject Re: CWL code questions
Date Fri, 05 Aug 2016 21:00:18 GMT
Hi Alan,

Thank you for the explanation and the link. It makes much more sense now.

Gale

On Fri, Aug 5, 2016 at 1:23 PM Alan Williams <alaninmcr@googlemail.com>
wrote:

> On 05-Aug-16 18:42, Gale Naylor wrote:
>
> Hello Gale
>
> > In CwlContextualView.java (I used the wrong filename in my previous
> email)
> > I'm also curious about the two private, final (but not static) constants
> > (?): configurationBean and activity.
> >
> > I'm not sure this StackOverflow answer is 100% relevant because
> > configurationBean and activity do not have initial values, but this is
> all
> > I've been able to find online:
> >
> http://stackoverflow.com/questions/1415955/private-final-static-attribute-vs-private-final-attribute
>
> If an attribute is not static then each instance of the class has its
> own attribute. So,
>
> private final CwlActivityConfigurationBean configurationBean;
>
> means that each CwlContextualView has its own configurationBean value.
>
> If an attribute is declared as static, then all instances of the class
> share the same attribute value.
>
> The private means that the value of the configurationBean cannot be
> accessed (directly) outside of the CwlContextualView. So
>
> fred = myCwlContextualView.configurationBean // will not work
>
> The final means that once the attribute has a value it cannot be
> changed. Even stronger, the value must be specified either in the
> declaration of the attribute, or when you construct an instance of
> CwlContextualView. (There are weird exceptions to the last sentence that
> are best ignored and never mentioned in polite company.)
>
> If you look at
>
> public CwlContextualView(CwlDumyActivity activity)
>
> which makes a CwlContextualView, it contains the line:
>
> this.configurationBean = activity.getConfiguration();
>
> So once you have made a CwlConfigurationView, it has a configurationBean
> attribute, that nothing else can see, and that has a fixed value.
>
> > Can anyone point me to information that would help me understand this
> > nomenclature?
>
> I think
>
> http://stackoverflow.com/questions/13772827/difference-between-static-and-final
> explains static and final well.
>
> > Thanks,
> >
> > Gale
>
> Alan
>
>

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