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Posted to users@wicket.apache.org by Fabio Cechinel Veronez <fa...@gmail.com> on 2011/09/05 03:18:50 UTC
Re: Can't properly override getConverter on FormComponent subclasses
do you mean something like ( in FormComponent class or one subclass ) :
....
/**
* subclasses would override it instead of getConverter(Class)
so no cast is necessary
*/
protected IConverter<T> getConverter()
{
// -- returns converter for FormComponent's type
return super.getConverter(getType());
}
@Override
public final <C> IConverter<C> getConverter(Class<C> type)
{
Class<T> fcType = getType();
// -- if type is a superclass of form component's type them use its
converter... otherwise uses default one
if (fcType != null && type.isAssignableFrom(fcType))
{
@SuppressWarnings("unchecked")
IConverter<C> converter = (IConverter<C>)getConverter();
return converter;
}
else
{
return super.getConverter(type);
}
}
....
??
On Mon, Aug 15, 2011 at 1:27 PM, vineet semwal
<vi...@gmail.com> wrote:
> The real problem is that Component has no generics.
> i agree with that so type parameter has to be used on the method
> currently unless a new method is added in the FormComponent ,the older
> method can just call the new method based on some conditional logic so
> nothings get broken in core..,the users will just have to override the
> new method but yeah i agree not very important ..
>
> thanks for the discussion in IRC too ! ;)
>
>
> On Mon, Aug 15, 2011 at 8:56 PM, Martin Grigorov <mg...@apache.org> wrote:
>> The real problem is that Component has no generics.
>> The tradeoff is that the library (FormComponents) do cast but all
>> users of them benefit without seeing this casting
>>
>> On Mon, Aug 15, 2011 at 6:21 PM, vineet semwal
>> <vi...@gmail.com> wrote:
>>> the signature of method is public final <C> IConverter<C>
>>> getConverter(Class<C> clazz) ;
>>>
>>> public IConverter<String> getConverter(Class<String> type)
>>> ^^ means not overriding correctly as method signature is not the same
>>>
>>> public <String> IConverter<String>getConverter(Class<String> type)
>>> now you have declared <String> as your type parameter but you will
>>> not be able to use String as class in method now as the
>>> declared <String> will now hide the String java data type..
>>>
>>> martin has already told you the way,currently casting appears to be
>>> the only way..
>>>
>>> On Mon, Aug 15, 2011 at 5:35 PM, Fabio Cechinel Veronez
>>> <fa...@gmail.com> wrote:
>>>> Sorry for previews post, wrong combinations of pressed keys =/
>>>>
>>>> I, will continue:
>>>>
>>>> Hello everybody,
>>>>
>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>> getConverter method of in a FormCompont subclass.
>>>>
>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>> as example, could be any type) when I try to to provide a specific
>>>> converter for my instance I'm implementing like that:
>>>>
>>>> TextField<String> tf = new TextField<String>("id") {
>>>>
>>>> @Override
>>>> public IConverter<String> getConverter(Class<String> type) {
>>>> // ...
>>>> return converter;
>>>> }
>>>> };
>>>>
>>>> But if I do like I get a compiler error saying:
>>>>
>>>> "Name clash: The method getConverter(Class<String>) of type new
>>>> TextField<String>(){} has the same erasure as getConverter(Class<C>)
>>>> of type Component but does not override it"
>>>> "The method getConverter(Class<String>) of type new
>>>> TextField<String>(){} must override or implement a supertype method"
>>>>
>>>> And when I try
>>>>
>>>> TextField<String> tf = new TextField<String>("id") {
>>>>
>>>> @Override
>>>> public <String> IConverter<String>
>>>> getConverter(Class<String> type) {
>>>> // ...
>>>> return converter;
>>>> }
>>>> };
>>>>
>>>> I get a compilation warn saying:
>>>>
>>>> "The type parameter String is hiding the type String"
>>>>
>>>>
>>>> I guess it happens 'cause getConverter uses a generic type C defined
>>>> at method level that is not the same generic type T defined at
>>>> TextField class level.
>>>>
>>>> What is the proper way to overwrite getConverter method?
>>>>
>>>>
>>>> On Mon, Aug 15, 2011 at 8:57 AM, Fabio Cechinel Veronez
>>>> <fa...@gmail.com> wrote:
>>>>> Hello everybody,
>>>>>
>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>> getConverter method of in a FormCompont subclass.
>>>>>
>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>> as example, could be any type) when I try to to provide a specific
>>>>> converter for my instance I
>>>>>
>>>>> --
>>>>> Fabio Cechinel Veronez
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Fabio Cechinel Veronez
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> thank you,
>>>
>>> regards,
>>> Vineet Semwal
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>
>>>
>>
>>
>>
>> --
>> Martin Grigorov
>> jWeekend
>> Training, Consulting, Development
>> http://jWeekend.com
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>>
>
>
>
> --
> thank you,
>
> regards,
> Vineet Semwal
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
> For additional commands, e-mail: users-help@wicket.apache.org
>
>
--
Fabio Cechinel Veronez
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
For additional commands, e-mail: users-help@wicket.apache.org
Re: Can't properly override getConverter on FormComponent subclasses
Posted by vineet semwal <vi...@gmail.com>.
i think it would need class because getConverter itself needs class
gettype() resolves class from the class name afaik ..
On Mon, Sep 5, 2011 at 5:17 PM, Fabio Cechinel Veronez
<fa...@gmail.com> wrote:
> why getFCConverter would need a Class as parameter?
>
> I mean, FormComponent whould be already known whether by getType or by
> T type... wouldn't it?
>
>
>
> On Mon, Sep 5, 2011 at 8:24 AM, vineet semwal
> <vi...@gmail.com> wrote:
>> In FormComponent class
>>
>> /**
>> * subclasses would override it instead of getConverter(Class)
>> so no cast is necessary
>> */
>> public IConverter<T> getFCConverter(Class<T>type)
>> {
>> // -- returns converter for FormComponent's type
>> return super.getConverter(type);
>> }
>>
>>
>> @Override
>> public <C> IConverter<C> getConverter(Class<C> type) {
>> Class<T> c = (Class<T>) type;
>> IConverter<C> converter = (IConverter<C>) getFCConverter(type);
>> return converter;
>> }
>>
>>
>>
>> i have only made some small changes here without using IDE so there
>> can be silly errors ,let me know if you think it shouldnt
>> be done this way or there is something wrong in code..
>>
>> also i think its very late for 1.5 at least ..
>>
>> thank you !
>>
>> On Mon, Sep 5, 2011 at 6:48 AM, Fabio Cechinel Veronez
>> <fa...@gmail.com> wrote:
>>> do you mean something like ( in FormComponent class or one subclass ) :
>>>
>>> ....
>>> /**
>>> * subclasses would override it instead of getConverter(Class)
>>> so no cast is necessary
>>> */
>>> protected IConverter<T> getConverter()
>>> {
>>> // -- returns converter for FormComponent's type
>>> return super.getConverter(getType());
>>> }
>>>
>>> @Override
>>> public final <C> IConverter<C> getConverter(Class<C> type)
>>> {
>>> Class<T> fcType = getType();
>>> // -- if type is a superclass of form component's type them use its
>>> converter... otherwise uses default one
>>> if (fcType != null && type.isAssignableFrom(fcType))
>>> {
>>> @SuppressWarnings("unchecked")
>>> IConverter<C> converter = (IConverter<C>)getConverter();
>>> return converter;
>>> }
>>> else
>>> {
>>> return super.getConverter(type);
>>> }
>>> }
>>> ....
>>> ??
>>>
>>> On Mon, Aug 15, 2011 at 1:27 PM, vineet semwal
>>> <vi...@gmail.com> wrote:
>>>> The real problem is that Component has no generics.
>>>> i agree with that so type parameter has to be used on the method
>>>> currently unless a new method is added in the FormComponent ,the older
>>>> method can just call the new method based on some conditional logic so
>>>> nothings get broken in core..,the users will just have to override the
>>>> new method but yeah i agree not very important ..
>>>>
>>>> thanks for the discussion in IRC too ! ;)
>>>>
>>>>
>>>> On Mon, Aug 15, 2011 at 8:56 PM, Martin Grigorov <mg...@apache.org> wrote:
>>>>> The real problem is that Component has no generics.
>>>>> The tradeoff is that the library (FormComponents) do cast but all
>>>>> users of them benefit without seeing this casting
>>>>>
>>>>> On Mon, Aug 15, 2011 at 6:21 PM, vineet semwal
>>>>> <vi...@gmail.com> wrote:
>>>>>> the signature of method is public final <C> IConverter<C>
>>>>>> getConverter(Class<C> clazz) ;
>>>>>>
>>>>>> public IConverter<String> getConverter(Class<String> type)
>>>>>> ^^ means not overriding correctly as method signature is not the same
>>>>>>
>>>>>> public <String> IConverter<String>getConverter(Class<String> type)
>>>>>> now you have declared <String> as your type parameter but you will
>>>>>> not be able to use String as class in method now as the
>>>>>> declared <String> will now hide the String java data type..
>>>>>>
>>>>>> martin has already told you the way,currently casting appears to be
>>>>>> the only way..
>>>>>>
>>>>>> On Mon, Aug 15, 2011 at 5:35 PM, Fabio Cechinel Veronez
>>>>>> <fa...@gmail.com> wrote:
>>>>>>> Sorry for previews post, wrong combinations of pressed keys =/
>>>>>>>
>>>>>>> I, will continue:
>>>>>>>
>>>>>>> Hello everybody,
>>>>>>>
>>>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>>>> getConverter method of in a FormCompont subclass.
>>>>>>>
>>>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>>>> as example, could be any type) when I try to to provide a specific
>>>>>>> converter for my instance I'm implementing like that:
>>>>>>>
>>>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>>>
>>>>>>> @Override
>>>>>>> public IConverter<String> getConverter(Class<String> type) {
>>>>>>> // ...
>>>>>>> return converter;
>>>>>>> }
>>>>>>> };
>>>>>>>
>>>>>>> But if I do like I get a compiler error saying:
>>>>>>>
>>>>>>> "Name clash: The method getConverter(Class<String>) of type new
>>>>>>> TextField<String>(){} has the same erasure as getConverter(Class<C>)
>>>>>>> of type Component but does not override it"
>>>>>>> "The method getConverter(Class<String>) of type new
>>>>>>> TextField<String>(){} must override or implement a supertype method"
>>>>>>>
>>>>>>> And when I try
>>>>>>>
>>>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>>>
>>>>>>> @Override
>>>>>>> public <String> IConverter<String>
>>>>>>> getConverter(Class<String> type) {
>>>>>>> // ...
>>>>>>> return converter;
>>>>>>> }
>>>>>>> };
>>>>>>>
>>>>>>> I get a compilation warn saying:
>>>>>>>
>>>>>>> "The type parameter String is hiding the type String"
>>>>>>>
>>>>>>>
>>>>>>> I guess it happens 'cause getConverter uses a generic type C defined
>>>>>>> at method level that is not the same generic type T defined at
>>>>>>> TextField class level.
>>>>>>>
>>>>>>> What is the proper way to overwrite getConverter method?
>>>>>>>
>>>>>>>
>>>>>>> On Mon, Aug 15, 2011 at 8:57 AM, Fabio Cechinel Veronez
>>>>>>> <fa...@gmail.com> wrote:
>>>>>>>> Hello everybody,
>>>>>>>>
>>>>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>>>>> getConverter method of in a FormCompont subclass.
>>>>>>>>
>>>>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>>>>> as example, could be any type) when I try to to provide a specific
>>>>>>>> converter for my instance I
>>>>>>>>
>>>>>>>> --
>>>>>>>> Fabio Cechinel Veronez
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Fabio Cechinel Veronez
>>>>>>>
>>>>>>> ---------------------------------------------------------------------
>>>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> thank you,
>>>>>>
>>>>>> regards,
>>>>>> Vineet Semwal
>>>>>>
>>>>>> ---------------------------------------------------------------------
>>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Martin Grigorov
>>>>> jWeekend
>>>>> Training, Consulting, Development
>>>>> http://jWeekend.com
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> thank you,
>>>>
>>>> regards,
>>>> Vineet Semwal
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Fabio Cechinel Veronez
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>
>>>
>>
>>
>>
>> --
>> thank you,
>>
>> regards,
>> Vineet Semwal
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>>
>
>
>
> --
> Fabio Cechinel Veronez
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
> For additional commands, e-mail: users-help@wicket.apache.org
>
>
--
thank you,
regards,
Vineet Semwal
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
For additional commands, e-mail: users-help@wicket.apache.org
Re: Can't properly override getConverter on FormComponent subclasses
Posted by Fabio Cechinel Veronez <fa...@gmail.com>.
why getFCConverter would need a Class as parameter?
I mean, FormComponent whould be already known whether by getType or by
T type... wouldn't it?
On Mon, Sep 5, 2011 at 8:24 AM, vineet semwal
<vi...@gmail.com> wrote:
> In FormComponent class
>
> /**
> * subclasses would override it instead of getConverter(Class)
> so no cast is necessary
> */
> public IConverter<T> getFCConverter(Class<T>type)
> {
> // -- returns converter for FormComponent's type
> return super.getConverter(type);
> }
>
>
> @Override
> public <C> IConverter<C> getConverter(Class<C> type) {
> Class<T> c = (Class<T>) type;
> IConverter<C> converter = (IConverter<C>) getFCConverter(type);
> return converter;
> }
>
>
>
> i have only made some small changes here without using IDE so there
> can be silly errors ,let me know if you think it shouldnt
> be done this way or there is something wrong in code..
>
> also i think its very late for 1.5 at least ..
>
> thank you !
>
> On Mon, Sep 5, 2011 at 6:48 AM, Fabio Cechinel Veronez
> <fa...@gmail.com> wrote:
>> do you mean something like ( in FormComponent class or one subclass ) :
>>
>> ....
>> /**
>> * subclasses would override it instead of getConverter(Class)
>> so no cast is necessary
>> */
>> protected IConverter<T> getConverter()
>> {
>> // -- returns converter for FormComponent's type
>> return super.getConverter(getType());
>> }
>>
>> @Override
>> public final <C> IConverter<C> getConverter(Class<C> type)
>> {
>> Class<T> fcType = getType();
>> // -- if type is a superclass of form component's type them use its
>> converter... otherwise uses default one
>> if (fcType != null && type.isAssignableFrom(fcType))
>> {
>> @SuppressWarnings("unchecked")
>> IConverter<C> converter = (IConverter<C>)getConverter();
>> return converter;
>> }
>> else
>> {
>> return super.getConverter(type);
>> }
>> }
>> ....
>> ??
>>
>> On Mon, Aug 15, 2011 at 1:27 PM, vineet semwal
>> <vi...@gmail.com> wrote:
>>> The real problem is that Component has no generics.
>>> i agree with that so type parameter has to be used on the method
>>> currently unless a new method is added in the FormComponent ,the older
>>> method can just call the new method based on some conditional logic so
>>> nothings get broken in core..,the users will just have to override the
>>> new method but yeah i agree not very important ..
>>>
>>> thanks for the discussion in IRC too ! ;)
>>>
>>>
>>> On Mon, Aug 15, 2011 at 8:56 PM, Martin Grigorov <mg...@apache.org> wrote:
>>>> The real problem is that Component has no generics.
>>>> The tradeoff is that the library (FormComponents) do cast but all
>>>> users of them benefit without seeing this casting
>>>>
>>>> On Mon, Aug 15, 2011 at 6:21 PM, vineet semwal
>>>> <vi...@gmail.com> wrote:
>>>>> the signature of method is public final <C> IConverter<C>
>>>>> getConverter(Class<C> clazz) ;
>>>>>
>>>>> public IConverter<String> getConverter(Class<String> type)
>>>>> ^^ means not overriding correctly as method signature is not the same
>>>>>
>>>>> public <String> IConverter<String>getConverter(Class<String> type)
>>>>> now you have declared <String> as your type parameter but you will
>>>>> not be able to use String as class in method now as the
>>>>> declared <String> will now hide the String java data type..
>>>>>
>>>>> martin has already told you the way,currently casting appears to be
>>>>> the only way..
>>>>>
>>>>> On Mon, Aug 15, 2011 at 5:35 PM, Fabio Cechinel Veronez
>>>>> <fa...@gmail.com> wrote:
>>>>>> Sorry for previews post, wrong combinations of pressed keys =/
>>>>>>
>>>>>> I, will continue:
>>>>>>
>>>>>> Hello everybody,
>>>>>>
>>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>>> getConverter method of in a FormCompont subclass.
>>>>>>
>>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>>> as example, could be any type) when I try to to provide a specific
>>>>>> converter for my instance I'm implementing like that:
>>>>>>
>>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>>
>>>>>> @Override
>>>>>> public IConverter<String> getConverter(Class<String> type) {
>>>>>> // ...
>>>>>> return converter;
>>>>>> }
>>>>>> };
>>>>>>
>>>>>> But if I do like I get a compiler error saying:
>>>>>>
>>>>>> "Name clash: The method getConverter(Class<String>) of type new
>>>>>> TextField<String>(){} has the same erasure as getConverter(Class<C>)
>>>>>> of type Component but does not override it"
>>>>>> "The method getConverter(Class<String>) of type new
>>>>>> TextField<String>(){} must override or implement a supertype method"
>>>>>>
>>>>>> And when I try
>>>>>>
>>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>>
>>>>>> @Override
>>>>>> public <String> IConverter<String>
>>>>>> getConverter(Class<String> type) {
>>>>>> // ...
>>>>>> return converter;
>>>>>> }
>>>>>> };
>>>>>>
>>>>>> I get a compilation warn saying:
>>>>>>
>>>>>> "The type parameter String is hiding the type String"
>>>>>>
>>>>>>
>>>>>> I guess it happens 'cause getConverter uses a generic type C defined
>>>>>> at method level that is not the same generic type T defined at
>>>>>> TextField class level.
>>>>>>
>>>>>> What is the proper way to overwrite getConverter method?
>>>>>>
>>>>>>
>>>>>> On Mon, Aug 15, 2011 at 8:57 AM, Fabio Cechinel Veronez
>>>>>> <fa...@gmail.com> wrote:
>>>>>>> Hello everybody,
>>>>>>>
>>>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>>>> getConverter method of in a FormCompont subclass.
>>>>>>>
>>>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>>>> as example, could be any type) when I try to to provide a specific
>>>>>>> converter for my instance I
>>>>>>>
>>>>>>> --
>>>>>>> Fabio Cechinel Veronez
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Fabio Cechinel Veronez
>>>>>>
>>>>>> ---------------------------------------------------------------------
>>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> thank you,
>>>>>
>>>>> regards,
>>>>> Vineet Semwal
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Martin Grigorov
>>>> jWeekend
>>>> Training, Consulting, Development
>>>> http://jWeekend.com
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> thank you,
>>>
>>> regards,
>>> Vineet Semwal
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>
>>>
>>
>>
>>
>> --
>> Fabio Cechinel Veronez
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>>
>
>
>
> --
> thank you,
>
> regards,
> Vineet Semwal
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
> For additional commands, e-mail: users-help@wicket.apache.org
>
>
--
Fabio Cechinel Veronez
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
For additional commands, e-mail: users-help@wicket.apache.org
Re: Can't properly override getConverter on FormComponent subclasses
Posted by vineet semwal <vi...@gmail.com>.
In FormComponent class
/**
* subclasses would override it instead of getConverter(Class)
so no cast is necessary
*/
public IConverter<T> getFCConverter(Class<T>type)
{
// -- returns converter for FormComponent's type
return super.getConverter(type);
}
@Override
public <C> IConverter<C> getConverter(Class<C> type) {
Class<T> c = (Class<T>) type;
IConverter<C> converter = (IConverter<C>) getFCConverter(type);
return converter;
}
i have only made some small changes here without using IDE so there
can be silly errors ,let me know if you think it shouldnt
be done this way or there is something wrong in code..
also i think its very late for 1.5 at least ..
thank you !
On Mon, Sep 5, 2011 at 6:48 AM, Fabio Cechinel Veronez
<fa...@gmail.com> wrote:
> do you mean something like ( in FormComponent class or one subclass ) :
>
> ....
> /**
> * subclasses would override it instead of getConverter(Class)
> so no cast is necessary
> */
> protected IConverter<T> getConverter()
> {
> // -- returns converter for FormComponent's type
> return super.getConverter(getType());
> }
>
> @Override
> public final <C> IConverter<C> getConverter(Class<C> type)
> {
> Class<T> fcType = getType();
> // -- if type is a superclass of form component's type them use its
> converter... otherwise uses default one
> if (fcType != null && type.isAssignableFrom(fcType))
> {
> @SuppressWarnings("unchecked")
> IConverter<C> converter = (IConverter<C>)getConverter();
> return converter;
> }
> else
> {
> return super.getConverter(type);
> }
> }
> ....
> ??
>
> On Mon, Aug 15, 2011 at 1:27 PM, vineet semwal
> <vi...@gmail.com> wrote:
>> The real problem is that Component has no generics.
>> i agree with that so type parameter has to be used on the method
>> currently unless a new method is added in the FormComponent ,the older
>> method can just call the new method based on some conditional logic so
>> nothings get broken in core..,the users will just have to override the
>> new method but yeah i agree not very important ..
>>
>> thanks for the discussion in IRC too ! ;)
>>
>>
>> On Mon, Aug 15, 2011 at 8:56 PM, Martin Grigorov <mg...@apache.org> wrote:
>>> The real problem is that Component has no generics.
>>> The tradeoff is that the library (FormComponents) do cast but all
>>> users of them benefit without seeing this casting
>>>
>>> On Mon, Aug 15, 2011 at 6:21 PM, vineet semwal
>>> <vi...@gmail.com> wrote:
>>>> the signature of method is public final <C> IConverter<C>
>>>> getConverter(Class<C> clazz) ;
>>>>
>>>> public IConverter<String> getConverter(Class<String> type)
>>>> ^^ means not overriding correctly as method signature is not the same
>>>>
>>>> public <String> IConverter<String>getConverter(Class<String> type)
>>>> now you have declared <String> as your type parameter but you will
>>>> not be able to use String as class in method now as the
>>>> declared <String> will now hide the String java data type..
>>>>
>>>> martin has already told you the way,currently casting appears to be
>>>> the only way..
>>>>
>>>> On Mon, Aug 15, 2011 at 5:35 PM, Fabio Cechinel Veronez
>>>> <fa...@gmail.com> wrote:
>>>>> Sorry for previews post, wrong combinations of pressed keys =/
>>>>>
>>>>> I, will continue:
>>>>>
>>>>> Hello everybody,
>>>>>
>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>> getConverter method of in a FormCompont subclass.
>>>>>
>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>> as example, could be any type) when I try to to provide a specific
>>>>> converter for my instance I'm implementing like that:
>>>>>
>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>
>>>>> @Override
>>>>> public IConverter<String> getConverter(Class<String> type) {
>>>>> // ...
>>>>> return converter;
>>>>> }
>>>>> };
>>>>>
>>>>> But if I do like I get a compiler error saying:
>>>>>
>>>>> "Name clash: The method getConverter(Class<String>) of type new
>>>>> TextField<String>(){} has the same erasure as getConverter(Class<C>)
>>>>> of type Component but does not override it"
>>>>> "The method getConverter(Class<String>) of type new
>>>>> TextField<String>(){} must override or implement a supertype method"
>>>>>
>>>>> And when I try
>>>>>
>>>>> TextField<String> tf = new TextField<String>("id") {
>>>>>
>>>>> @Override
>>>>> public <String> IConverter<String>
>>>>> getConverter(Class<String> type) {
>>>>> // ...
>>>>> return converter;
>>>>> }
>>>>> };
>>>>>
>>>>> I get a compilation warn saying:
>>>>>
>>>>> "The type parameter String is hiding the type String"
>>>>>
>>>>>
>>>>> I guess it happens 'cause getConverter uses a generic type C defined
>>>>> at method level that is not the same generic type T defined at
>>>>> TextField class level.
>>>>>
>>>>> What is the proper way to overwrite getConverter method?
>>>>>
>>>>>
>>>>> On Mon, Aug 15, 2011 at 8:57 AM, Fabio Cechinel Veronez
>>>>> <fa...@gmail.com> wrote:
>>>>>> Hello everybody,
>>>>>>
>>>>>> I'm using wicket 1.5-RC5.1 and I'm having problem to override
>>>>>> getConverter method of in a FormCompont subclass.
>>>>>>
>>>>>> Well, lets say I have a TextField<Date> (I'm using j.u.Date here just
>>>>>> as example, could be any type) when I try to to provide a specific
>>>>>> converter for my instance I
>>>>>>
>>>>>> --
>>>>>> Fabio Cechinel Veronez
>>>>>>
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Fabio Cechinel Veronez
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> thank you,
>>>>
>>>> regards,
>>>> Vineet Semwal
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Martin Grigorov
>>> jWeekend
>>> Training, Consulting, Development
>>> http://jWeekend.com
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>>> For additional commands, e-mail: users-help@wicket.apache.org
>>>
>>>
>>
>>
>>
>> --
>> thank you,
>>
>> regards,
>> Vineet Semwal
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
>> For additional commands, e-mail: users-help@wicket.apache.org
>>
>>
>
>
>
> --
> Fabio Cechinel Veronez
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@wicket.apache.org
> For additional commands, e-mail: users-help@wicket.apache.org
>
>
--
thank you,
regards,
Vineet Semwal
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