Re: [riena-dev] RienaDefaultLnf considered harmful ?

[Stefan Liebig <Stefan.Liebig@xxxxxxxxxxxx>]

My personal favorite is a), it is:
- explicit
- safe

A first look at the usage of the getXXXSetting without default parameter 
shows that sometimes a default will be applied by the calling code 
sometimes not causing an NPE if not defined.
So, a question arises: Is it an error if a setting has not been defined?

Tschüß,
Stefan

On 15.02.2010 23:37, Christian Campo wrote:
> there is also
>
> c) that all getXXXSetting method HAVE to return a non null value, so changing the contract. that would make life easier vor teh components using LnF.
>
> @Thorsten?
>
> christian
>
> Am 15.02.2010 um 21:30 schrieb Elias Volanakis:
>
>    
> > Hi everybody,
> >
> > here's something to discuss:
> >
> > I realized that we a dozen or more potential null-pointer-exceptions
> > waiting to happen, because of the way we use the RienaDefaultLnf:
> >
> > Example 1:
> > boolean on = lnf.getBooleanSetting(LnfKeyConstants.DISABLED_MARKER_ADVANCED);
> >
> > Example 2:
> > shellRenderer.setCloseable(lnf.getBooleanSetting(LnfKeyConstants.TITLELESS_SHELL_SHOW_CLOSE));
> >
> > Example 3:
> > private int getSwitchterHeight() {
> >   int margin = LnfManager.getLnf().getIntegerSetting(LnfKeyConstants.SUB_APPLICATION_SWITCHER_HEIGHT);
> >   return margin;
> > }
> >
> > The problem here is that the getXXXSetting methods may return null,
> > which causes an NPE if used together with auto-boxing (Integer-to-int,
> > Boolean-to-boolean).
> >
> > (a) My favorite approach would be to deprecate/remove these methods
> > and use a second variant that always needs a default value:
> > lnf.getBooleanSetting(KEY, false); lnf.getIntegerSetting(KEY, 0). We
> > already have these methods :-)
> > (b) If we don't go for (a), we have to at least go over all places in
> > the code and make sure we handle a null return value. However this
> > will not prevent it from re-happening later.
> >
> > Looking forward to feedback,
> > Elias.
> >
> > --
> > Elias Volanakis | Technical Lead | http://eclipsesource.com
> > elias@xxxxxxxxxxxxxxxxx | +1 503 929 5537 | @evolanakis
> > _______________________________________________
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> > riena-dev@xxxxxxxxxxx
> > https://dev.eclipse.org/mailman/listinfo/riena-dev
> >      
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