The only problem right now is the cast to Component[]. The fix is easy, just change it to Object[]. The optimization makes a lot of sense and there is reason why it can't really be simple.
-Matej On Mon, Dec 1, 2008 at 2:29 AM, jWeekend <[EMAIL PROTECTED]> wrote: > > MarkupContainer's children field is declared as an Object and can refer to > > a ChildList - which is a List, hopefully (until it's genericised) of > Components, > an Object[] - again, hopefully of Components, > a Component - ie a single child, or, even > a ComponentSourceEntry - a bare-bones representation of only the > "essentials" of a Component from which it can be reconstructed. > > I assume MarkupContainer's implementation was refactored (_from_ something > much more straight-forward) as an optimisation, in particular related to > serialisation, with the argument probably along the lines of: it is common > for a MarkupContainer to have just a single child, so we don't want the > luggage of a List in those cases etc ... > > All this can make MarkupContainer pretty fragile, easy to accidentally > break. If the optimisation argument is really strong enough (I expect it > must have been at the time and may still be), at the very least, all the > messy operations on "children" could be encapsulated in a class (perhaps > called FunkyChildren, possibly as an inner class if it necessarily needs > access to its owning MarkupContainer instance's guts and is never used > outside this context) that exposes only friendly methods like > set(int index,Component child) and > remove(Component child) > etc ... > > Apart from simplifying MarkupContainer, the above design would also have the > benefit of making it possible to address the problem in hand (with the > illegal runtime array cast), mend what's broken and test this funky, > edge-case(?) behaviour without having to interfere with MarkupContainer. > And, if there's a simpler/better/more efficient FunkyChildren possible for > 1.5 just plug in the new implementation. Importantly, as this an internal > change (internal to MarkupContainer), there will be no API break (neither > within Wicket nor in the public API). > > Regards - Cemal > http://www.jWeekend.co.uk http://jWeekend.co.uk > > > > Matej Knopp-2 wrote: >> >> this >> >> sorted = Arrays.asList((Component[])children); >> >> doesn't look right. I think it should have been (Object[])children >> although a type check would be appropriate. >> >> -Matej >> >> On Fri, Nov 28, 2008 at 7:30 PM, jWeekend <[EMAIL PROTECTED]> >> wrote: >>> >>> Not quite. >>> String[] bO = (String[])(new Object[]{"yes","we","can"}); >>> compiles but fails at run time. >>> >>> Regards - Cemal >>> http://www.jWeekend.co.uk http://jWeekend.co.uk >>> >>> >>> >>> Valentine2008 wrote: >>>> >>>> It will bring the compilation error when trying to cast arrays in Java. >>>> >>>> So you mean it is a bug in Wicket? >>>> >>>> >>>> Timo Rantalaiho wrote: >>>>> >>>>> On Thu, 27 Nov 2008, Valentine2008 wrote: >>>>>> java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to >>>>>> [Lorg.apache >>>>>> .wicket.Component; >>>>>> at >>>>>> org.apache.wicket.MarkupContainer.iterator(MarkupContainer.java:478) >>>>>> ......... >>>>>> >>>>>> The code on line 478 of MarkupContainer.java is: >>>>>> sorted = Arrays.asList((Component[])children); >>>>>> >>>>>> Is it a bug of Wicket? >>>>> >>>>> No, I think it's a limitation of Java. You cannnot cast >>>>> arrays. >>>>> >>>>> Best wishes, >>>>> Timo >>>>> >>>>> -- >>>>> Timo Rantalaiho >>>>> Reaktor Innovations Oy <URL: http://www.ri.fi/ > >>>>> >>>>> --------------------------------------------------------------------- >>>>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>>>> For additional commands, e-mail: [EMAIL PROTECTED] >>>>> >>>>> >>>>> >>>> >>>> >>> >>> -- >>> View this message in context: >>> http://www.nabble.com/Bug-of-Wicket-1.3.4-when-iterate-the-form-using-iterator%28Comparator%29--tp20723903p20738179.html >>> Sent from the Wicket - User mailing list archive at Nabble.com. >>> >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>> For additional commands, e-mail: [EMAIL PROTECTED] >>> >>> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: [EMAIL PROTECTED] >> For additional commands, e-mail: [EMAIL PROTECTED] >> >> >> > > -- > View this message in context: > http://www.nabble.com/Bug-of-Wicket-1.3.4-when-iterate-the-form-using-iterator%28Comparator%29--tp20723903p20764684.html > Sent from the Wicket - User mailing list archive at Nabble.com. > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
