Hi
QNAme is an XML-ism and the API is XML-free (as I said, use of XML is just one
way to back the API). So I am extremely reluctant to using QName (regardless of
whether we use javax.xml.QName or define our own QName class). Always consider
the case where an QbjectClassDefinition might be backed by a MetaTypeProvider
service and not XML.
As for the interface (except QName question), I am fine.
However, I could assume we could have the name, if it comes from XML, to be
something like
{url}localname
or
prefix:localname
And, of course, the {url} or prefix: prefix would be omitted for the default
namespace (empty string) or the namespace of the metatype descriptor.
Regards
Felix
Am 14.01.2013 um 07:43 schrieb <[email protected]>
<[email protected]>:
> O.K. I see.
>
> Then I would suggest to add something like the following interface to
> AttributeDefinition and ObjectClassDefinition:
>
> public interface ExtraAttributes {
>
> /**
> * List the {@link QName}s of extra XML attributes.
> *
> * @return an {@link Iterator} producing the {@link QName}s of the
> extra attributes.
> */
> public Iterator<QName> getExtraAttributeNames();
>
> /**
> * Retrieve the value of an extra XML attribute.
> *
> * @param name {@link QName} of the extra attribute, whose value should
> be retrieved.
> * @return the value of the extra attribute or <code>null</code> if no
> attribute with
> * that name exists.
> */
> public String getExtraAttributeValue(QName name);
> }
>
> However, my initial question about QName and XML API support arises again as
> we are using
> QName here. Note, using just a String as argument to getExtraAttributeValue
> will not work, as several
> attributes with the same name but different Namespaces (prefixes) might exist
> on the same
> Element.
>
> Regards
> Alex
>
> --
> finnova AG Bankware
> Alexander Berger
> Software Architect
> Merkurstrasse 6
> CH-5600 Lenzburg
> Tel: +41 (0)62 886 48 07 (direkt)
> Tel: +41 (0)62 886 47 47 (zentrale)
> Fax: +41 (0)62 886 48 88
> mailto:[email protected]
> http://www.finnova.ch
>
> -----Ursprüngliche Nachricht-----
> Von: Felix Meschberger [mailto:[email protected]]
> Gesendet: Samstag, 12. Januar 2013 22:15
> An: [email protected]
> Betreff: Re: Metatype Service - OptionalAttributes - extra XML attributes
> with namespace support
>
>
> Am 10.01.2013 um 17:14 schrieb <[email protected]>
> <[email protected]>:
>
>> That's a good question.
>>
>> I think in terms of an API for accessing extra XML attributes, chances
>> are good that such an API could be standardized (at least
>> technically). But in terms of the specific "extra XML attributes" I
>> see no way to get them standardized. And I guess that is the reason
>> why the XSD (XML Schema) for the metatype descriptions allows for extra
>> attributes (which reside in another XML namespace). Maybe someone that has
>> worked on the specification might clarify what the intention about allowing
>> the extra attributes was.
>
> Originally the idea was, that the same XML files would be used for metatype
> descriptors and other applications. Which is why it is lenient to other data.
>
>>
>> Unless I know more about the matter I long for the following:
>>
>> 1. Anybody can enrich the metatype descriptions with his own
>> (specific/individual) metadata.
>> The current specification supports this by allowing extra XML attributes
>> that reside in another namespace (##other).
>>
>> 2. An API to list respectively retrieve those extra attributes. And ideally
>> such an API could become part of the
>> metatype specification (new methods on the already existing interfaces or
>> on new sub-interfaces).
>
> Please also consider that XML files are only one source for metatype
> descriptors. Access is always through API which can also be implemented
> without having XML.
>
> One option I could conceive, though, would be that we extend the
> AttributeDefinition interface with a new method:
>
> String getExtraAttribute(String name);
>
> which returns the named attribute.
>
> WDYT ?
>
> Regards
> Felix
>
>
>>
>> Regards
>> Alex
>>
>>
>> -----Ursprüngliche Nachricht-----
>> Von: Felix Meschberger [mailto:[email protected]]
>> Gesendet: Donnerstag, 10. Januar 2013 15:58
>> An: [email protected]
>> Betreff: Re: Metatype Service - OptionalAttributes - extra XML
>> attributes with namespace support
>>
>> Hi Alex,
>>
>> Sorry, I missed your message from last week.
>>
>> Am 10.01.2013 um 13:34 schrieb <[email protected]>
>> <[email protected]>:
>>
>>> I want to add some extra attributes to the metadata (XML) which will then
>>> be used by a (special) administration console which knows about that extra
>>> attributes. These extra attributes will be used to allow a more concise
>>> representation of Configurations in the Graphical User Interface (GUI). For
>>> example to show a value from a certain configuration property instead of
>>> its PID in the GUI, as PIDs are quite meaningless to the average User.
>>
>> Thanks. The reason for asking is, whether your use case is in fact something
>> that could be generalized to properly enhance the API. And thus to try to
>> get it into the specification.
>>
>> Do you think such a generalization might be possible ?
>>
>> Regards
>> Felix
>>
>>>
>>> Regards
>>> Alex
>>>
>>> --
>>> finnova AG Bankware
>>> Alexander Berger
>>> Interface Development
>>> Merkurstrasse 6
>>> CH-5600 Lenzburg
>>> Tel: +41 (0)62 886 48 07 (direkt)
>>> Tel: +41 (0)62 886 47 47 (zentrale)
>>> Fax: +41 (0)62 886 48 88
>>> mailto:[email protected]
>>> http://www.finnova.ch
>>>
>>> -----Ursprüngliche Nachricht-----
>>> Von: Felix Meschberger [mailto:[email protected]]
>>> Gesendet: Freitag, 4. Januar 2013 14:41
>>> An: [email protected]
>>> Betreff: Re: Metatype Service - OptionalAttributes - extra XML
>>> attributes with namespace support
>>>
>>> Hi,
>>>
>>> Am 04.01.2013 um 08:23 schrieb <[email protected]>
>>> <[email protected]>:
>>>
>>>> Hi
>>>>
>>>> I intend to use extra (optional) XML attributes with the Metatype Service.
>>>
>>> Before commenting in detail, I would be interested to know what exactly you
>>> want to achieve by using additional attributes on object class and
>>> attribute definitions.
>>>
>>> Regards
>>> Felix
>>>
>>>
>>>> For this purpose I examined the
>>>> Felix metatype service implementation and found the class
>>>> org.apache.felix.metatype.OptionalAttributes,
>>>> which is extended by AD, OCD, ... . But unluckily this class is
>>>> neither inherited by LocalizedObjectClassDefinition nor by
>>>> LocalizedAttributeDefinition, which makes it quite useless for the moment.
>>>>
>>>> Another Problem is that OptionalAttributes does not support XML namespaces
>>>> for the attribute names.
>>>> The underlying Map should use something like
>>>> javax.xml.namespace.QName as key and not just the name of the
>>>> attribute (String). Note, XML namespace support is crucial as extra XML
>>>> attribute have to be in a different (##other) namespace (see "Metatype
>>>> Service Specifiaction" (Version 1.2), section 105.9 "XML Schema").
>>>>
>>>> The above observations lead me to the following question:
>>>>
>>>> 1. Is it still a requirement for Felix subprojects to avoid
>>>> dependencies on packages like java.xml.** and rely on kxml2 instead?
>>>> a. If so, then I could try create a patch for metatype service which
>>>> will add support for extra XML attributes (including XML namespace support
>>>> but not using javax.xml.namespace.QName),
>>>> so that extra XML attributes could be retrieved from AD, OCD, ...,
>>>> LocalizedObjectClassDefinition and LocalizedAttributeDefinition instances.
>>>> b. If not, then I could try to create a similar patch as described
>>>> above (a) but using javax.xml.namespace.QName instead.
>>>>
>>>> Note, the class javax.xml.namespace.QName is part of JavaSE since version
>>>> 1.5 older versions as well as JavaME do not contain that class.
>>>>
>>>> Alex
>>>>
>>>>
>>>
>>
>
