The Hint system was only recently hooked up - and I found a few problems with it during that process. Please assume that any troubles you have are just a QA problem (and something you can fix; and have permission to fix).
For anything to do with runtime evaluation of filters you should look into the environmental variable part of the specification; and think about how we can make use of this ... My best idea is to make a utility function can can be used with a Map to resolve all the environmental variables in an expression to literals. Jody > btw, > If I want to pass hints to FilterFactory, does it necessarly needs to declare > which ones it accepts through getImplementationHints()? > > I ask because I'm looking at GridCoverageFactory and, thgough it can handle > some hints at its constructor, it just returns an empty map in > getImplementationHints (inherited from AbstractFactory). > > But if I do the same in FilterFactoryImpl, the hints are never passed, seems > an instance preiously created without hints were cached somehow and after > that the constructor that expects Hints gets never called, even if I pass an > actual Hints to CommonFactoryFinder.getFilterFactory(Hints). > > Is that correct? are they actually behaving differently? am I just not making > sense of all this? > > cheers, > > Gabriel > > > On Wednesday 23 May 2007 14:25:36 Gabriel Roldán wrote: > >> Hi Justin, >> >> I was trying to imeplement a namespace aware property accessor to work with >> AttributeExpressionImpl, and got a bit confused on the use of Hints. >> >> I could achieve the same result I'm looking for by hacking my own >> FilterFactory implementation that creates namespace aware PropertyName >> expressions, but would like to make my mind clear about the following issue >> first: >> >> PropertyAccessorFactory.createPropertyAccessor(...) receives a Hints. >> It is only called by PropertyAccessors.findPropertyAccessor, which should >> pass the Hints to PropertyAccessorFactory.createPropertyAccessor. >> In turn, PropertyAccessors.findPropertyAccessor gets called by >> AttributeExpressionImpl.evaluate(Object), but allways passes null in place >> of Hints. >> So the question is, how do I actually pass some hints to >> PropertyAccessors.findPropertyAccessor ? >> >> If it is just an unfinished edge of the thing, I wonder if the following >> would be correct: >> - Add a constructor to AttributeExpressionImpl that receives a Hints. >> - Make FilterFactoryImpl pass the Hints it receives in its constructor to >> the AttributeExpressionImpl it creates. >> >> I guess I'm making something very wrong, as the above approach wouldn't >> work neither, as I can't pass a hints with, say, an instance of >> NameSpaceSupport as value, because FactoryRegistry will check that for >> equality against what FilterFactory.getImplementationHints() returned. So >> it seems there's no way of passing a "context" to the filter factory, >> neither to the >> AttributeExpressions, in order to be able of making them namespace aware. >> >> and afaik, at the geotools level we arent applying dependency injection for >> this kind of stuff neither... >> >> suggestions? >> >> >> >> Gabriel >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by DB2 Express >> Download DB2 Express C - the FREE version of DB2 express and take >> control of your XML. No limits. Just data. Click to get it now. >> http://sourceforge.net/powerbar/db2/ >> _______________________________________________ >> Geotools-devel mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/geotools-devel >> > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > _______________________________________________ > Geotools-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geotools-devel > ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
