The problem is that the Collection in a ComplexAttribute is of properties, not attributes. GeoAPI is a representation of the ISO Feature Model. XML attributes are an encoding artifact. Not all attributes can be converted back to GeoAPI. Some are calculated at encoding time. For example, to remove a duplicate feature, a feature property type might be encoded by xlink:href. In contrast, when encoding some feature property types, we may not have the property, only its URN, and so encode the property by reference by smuggling the URN in UserData.
I often feel that we are misusing GeoAPI because we are building a tree to represent the encoded XML we want, and hacking the bindings to accept them. I am beginning to suspect that we should use GeoAPI to represent the feature model, and have the encoder handle the encoding. Another example is the use of property types. Are these even present in the ISO model, or are they a GML encoding artifact? They appear to me to be present only to cause the striping rule to be observed. Some UML (see properties, and no property types): https://www.seegrid.csiro.au/twiki/bin/view/CGIModel/GeologicUnit https://www.seegrid.csiro.au/twiki/bin/view/CGIModel/GeologicFeature Can anyone tell me how gml:MeasureType should be represented as a GeoAPI ComplexAttribute? Where does the value live? Where does uom live? At the moment we smuggle uom in UserData and set the value in a property. I suspect everything should just be a property. I have never got a straight answer. To this day, I do not know if we are using GeoAPI correctly. Kind regards, Ben. Rob Atkinson wrote: > The constructor takes a Collection<Properties> which is hard coded to > Collections.EMPTY_LIST. > > In the patch I attached was an experimental modification to GMLSchema > : I've updated this and attached it separately so it uses Attribute > not Property, now Jody has made the PropertyImpl abstract. > > Ther MeasureTypeBindingTest still fails however, so I'm not sure what > I'm missing. One reason I was trying to generate GMLSchema with > attributes was to look for clues as to excalty how to represent an > attribute so the encoder finds it. > > Rob > > On Fri, Sep 4, 2009 at 12:30 PM, Justin Deoliveira<[email protected]> > wrote: >> Hi all, >> >> I am working on regenerating the GMLSchema class complete with >> attributes and i am not 100% sure how attributes are represented in our >> feature model with regard to appschema. I understand that they are >> somewhat hacked in for encoding purposes into client properties. But how >> should i represent them in the types in GMLSchema? Ben and folks can >> hopefully provide some guidance. >> >> -Justin >> >> -- >> Justin Deoliveira >> OpenGeo - http://opengeo.org >> Enterprise support for open source geospatial. >> >> ------------------------------------------------------------------------------ >> Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day >> trial. Simplify your report design, integration and deployment - and focus on >> what you do best, core application coding. Discover what's new with >> Crystal Reports now. http://p.sf.net/sfu/bobj-july >> _______________________________________________ >> Geotools-devel mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/geotools-devel >> > > ------------------------------------------------------------------------------ > Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day > trial. Simplify your report design, integration and deployment - and focus on > what you do best, core application coding. Discover what's new with > Crystal Reports now. http://p.sf.net/sfu/bobj-july > _______________________________________________ > Geotools-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geotools-devel > -- Ben Caradoc-Davies <[email protected]> Software Engineer, CSIRO Exploration and Mining Australian Resources Research Centre 26 Dick Perry Ave, Kensington WA 6151, Australia ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
