>From my original post on this topic:
public class StringModel extends Model<String>
-Doug
Peter Ertl wrote:
>
> StringModel looks ambigious to me, will it extend
>
> - LoadableDetachableModel
> - IModel
> - Model
> - AbstractReadOnlyModel
> - ....
>
> ???
>
>
>
>
> Am 14.05.2008 um 15:47 schrieb Doug Donohoe:
>
>>
>> Let me outline what I believe the benefits are. For example:
>>
>> add(new Label<String>("tournamentName", tournament.getName()));
>> add(new Label<String>("hostName", game.getHostPlayer()));
>> row.add(new AttributeModifier("class", true, new
>> Model<String>(row.getIndex() % 2 == 0 ? "odd" : "even")));
>>
>> add(new StringLabel("tournamentName", tournament.getName()));
>> add(new StringLabel("hostName", game.getHostPlayer()));
>> row.add(new AttributeModifier("class", true, new
>> StringModel(row.getIndex()
>> % 2 == 0 ? "odd" : "even")));
>>
>> Sure, it seems like a small difference and a saving of two
>> characters, but
>> here is what I believe are the benefits of doing this:
>>
>> 1) I can more easily use the features of my IDE such as auto-
>> completion
>>
>> 2) Find Usages is more accurate (at least in IntelliJ, where I'm not
>> aware
>> of a find-usages that scopes to a particular generic type)
>>
>> 3) Let's face it, Generics clutters up your code and makes it harder
>> to
>> read. This simplifies things a bit.
>>
>> In answer to Martijn's assumption (in a separate post) that I was
>> going to
>> iterate over all java types and all wicket types: that is an
>> incorrect
>> assumption. Obviously, I would want to pick the most common use
>> cases and
>> seek feedback from the community. Let us not dismiss it outright. I
>> believe this is a valid topic of conversation. Generics are new to
>> Wicket
>> and still unused by many Java APIs and likely new to many
>> programmers. I
>> can tell you that using classes such as this made it much quicker
>> and easier
>> to remove all the warnings that showed up in my code when I migrated
>> to 1.4.
>> It seems easier to replace common usage from before (new Label(...))
>> with
>> new StringLabel(...) rather than new Label<String> (even typing
>> that now
>> was more difficult). In any case, there may be some complaining
>> about the
>> extensive use of Generics in 1.4 once it is released. This may make
>> it
>> easier to transition. Maybe not. At least let's be open to
>> discussing it.
>>
>> Finally, in answer to the point about "negating the point of
>> generics", I
>> respectfully disagree. One major point of generics is to avoid code
>> duplication of boilerplate code. It it weren't for the need to
>> create
>> constructors, there wouldn't be any duplicated code. I agree that
>> it is a
>> fine balance to strike, but there are competing needs of readability
>> and
>> maintainability.
>>
>> -Doug
>>
>>
>> Hoover, William wrote:
>>>
>>> imho, that seems like that adds a lot of unnecessary code. One of the
>>> nice things about Wicket is that it keeps the bloat to a minimum.
>>>
>>> -----Original Message-----
>>> From: Doug Donohoe [mailto:[EMAIL PROTECTED]
>>> Sent: Wednesday, May 14, 2008 8:21 AM
>>> To: [email protected]
>>> Subject: Re: Using generics with some non-generic classes in Wicket
>>>
>>>
>>> Somewhat related to this thread, when I moved to generics win Wicket
>>> 1.4, I created some utility classes such as:
>>>
>>> public class VoidContainer extends WebMarkupContainer<Void> public
>>> class VoidPanel extends Panel<Void> public class StringLabel
>>> extends
>>> Label<String>
>>>
>>> public class IntegerModel extends Model<Integer> public class
>>> StringModel extends Model<String> public class DateModel extends
>>> Model<Date> public class DoubleModel extends Model<Double>
>>>
>>> And so on. This made my wicket code cleaner and easier to use. I
>>> think
>>> the Wicket 1.4 generics implementation is headed in the right
>>> direction.
>>> It was a pain at first because I had to parameterize everything, but
>>> creating convenience classes like this made it easier.
>>>
>>> I'm thinking about creating a patch with a suite of these types of
>>> classes because I think users will want something like this.
>>>
>>> -Doug
>>>
>>>
>>> Johan Compagner wrote:
>>>>
>>>> The problem is that wicket needs an annotation
>>>>
>>>> <genericsOptional>
>>>>
>>>> so that all the warnings about raw types are gone.
>>>>
>>>> A component only has to be generic if you use the IModel constructor
>>>> or call getModel(), getModelObject() methods..
>>>> for the rest it is not really needed
>>>>
>>>> johan
>>>>
>>>> On Wed, May 14, 2008 at 9:28 AM, Sebastiaan van Erk
>>>> <[EMAIL PROTECTED]>
>>>> wrote:
>>>>
>>>>> My post kind of missed the point, I shouldn't post when I'm already
>>>>> half asleep. :-)
>>>>>
>>>>> Obviously MarkupContainer satisfies the MarkupContainer<?> in a
>>>>> method argument, so it accepts the raw type. However, it
>>>>> generates a
>>>>> warning because the method says it's generified, so you should be
>>>>> using the generic type.
>>>>>
>>>>> Johan Compagner wrote:
>>>>>
>>>>>> I dont care, because i cant do any thing with the ? The only thing
>>>>>> it enforces is that it must now be a generic class which is
>>>>>> annoying. Not to mention that in that area eclipse and javac
>>>>>> accept
>>>
>>>>>> different things....
>>>>>>
>>>>>
>>>>> The reason it warns you to use generics when generics are wanted is
>>>>> because Sun wants to be able to make it *required* (in a future
>>>>> release) to use generics where generics are wanted; at least, so I
>>>>> read... I think in the real world they wouldn't dare to do this
>>>>> because it would piss off so many users and break so much
>>>>> stuff. :-)
>>>>>
>>>>> But the idea is that if something is generified you should be
>>>>> using a
>>>
>>>>> type parameter, and using a raw type is *purely* for backwards
>>>>> compatibility with legacy code.
>>>>>
>>>>> Regards,
>>>>> Sebastiaan
>>>>>
>>>>> So or we in wicket dont use <?> any where and have supress warning
>>>>>> everywhere for that or we do use it and then suddenly it is in my
>>>>>> eyes restricted to much.
>>>>>>
>>>>>
>>>>> I don't understand
>>>>>
>>>>>
>>>>>> On 5/14/08, Sebastiaan van Erk <[EMAIL PROTECTED]> wrote:
>>>>>>
>>>>>>> Johan Compagner wrote:
>>>>>>>
>>>>>>>> yes thats the reason
>>>>>>>>
>>>>>>>> you are calling the method add with a generified component but
>>>>>>>> that container itself is not generified
>>>>>>>>
>>>>>>>> i dont like this about generics expecially the onces like this:
>>>>>>>>
>>>>>>>> add(MarkupContainer<?> container)
>>>>>>>>
>>>>>>>> then suddenly a none generified component cant be added...
>>>>>>>> thats really stupid <?> should mean anything.. including none
>>>>>>>> generics
>>>>>>>>
>>>>>>> No, that's not correct. For example, List<?> is much more
>>>>>>> restrictive than a raw List (which is a List). To a raw list you
>>>>>>> can add an instance of any type whatever, i.e., list.add(new
>>>>>>> Object()). But in List<?> the ? is a wildcard which says it could
>>>
>>>>>>> be any type there, i.e., it could be a List<Integer>. But you
>>>>>>> can't add a new Object() to a List<Integer>!
>>>>>>>
>>>>>>> Thus MarkupContainer<?> means "MarkupContainer parameterized by
>>>>>>> some unknown type", and *not* MarkupContainer parameterized by
>>>>>>> Object, which is what the raw type means.
>>>>>>>
>>>>>>> Regards,
>>>>>>> Sebastiaan
>>>>>>>
>>>>>>> johan
>>>>>>>>
>>>>>>>>
>>>>>>>> On Tue, May 13, 2008 at 5:55 PM, Stefan Simik <
>>>>>>>> [EMAIL PROTECTED]>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>> I have one idea,
>>>>>>>>>
>>>>>>>>> the reason of the warnigs is, that parent of
>>>>>>>>> AjaxPagingNavigator is PagingNavigator, which has parent
>>>>>>>>> Panel ---> that is not parameterized.
>>>>>>>>>
>>>>>>>>> The same problem is with LoopItem, which extends the
>>>>>>>>> WebMarkupContainer ---> that is not parameterized.
>>>>>>>>>
>>>>>>>>> ? could this be the reason ?
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Stefan Simik wrote:
>>>>>>>>>
>>>>>>>>>> Mhmm, it is meaningful ;) I will know in future, thx
>>>>>>>>>>
>>>>>>>>>> One of the last occuring warning is, when working with
>>>>>>>>>> MarkupContainer#add(...) or #addOrReplace(...) method.
>>>>>>>>>>
>>>>>>>>>> Example: I have a simple AjaxPagingNavigator, to which I
>>>>>>>>>> add a simple ListView
>>>>>>>>>>
>>>>>>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> --
>>>>>>>>>> ListView<Integer> menu = new ListView<Integer>("id",
>>> numbers){
>>>>>>>>>> //....populate metods
>>>>>>>>>> }
>>>>>>>>>> add(menu); //warning here
>>>>>>>>>>
>>>>>>>>>> The warning says:
>>>>>>>>>> "Type safety: The method add(Component...) belongs to the
>>>>>>>>>> raw type MarkupContainer.
>>>>>>>>>> References to generic type MarkupContainer<T> should be
>>>>>>>>>> parameterized"
>>>>>>>>>>
>>>>>>>>>> I cannot find out, what's the warning reason, because
>>>>>>>>>> ListView self is parameterized.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>> View this message in context:
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>> http://www.nabble.com/Using-generics-with-some-non-generic-classes-in
>>>>> -Wicket-tp17208928p17212015.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/Using-generics-with-some-non-generic-classes-in-Wi
>>> cket-1.4M1-tp17208928p17229755.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/Using-generics-with-some-non-generic-classes-in-Wicket-1.4M1-tp17208928p17231467.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/Using-generics-with-some-non-generic-classes-in-Wicket-1.4M1-tp17208928p17232467.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]
