[Geotools-devel] FactoryRegistry Hints - nice summary

[Jody G. <jga...@re...>]

Thanks Martin - that is a good summary :-)

I am using it to update the long request instructions on how to use hints:
- http://docs.codehaus.org/display/GEOTDOC/01+Factory+and+Hint+Tutorial

Cheers,
Jody


Martin Desruisseaux wrote:
> I think that this use case is already well covered by current design:
>
> - User create the following in its own application space
>   (not a geotools global setting):
>
>   private static final Hints myApplicationSetting = new Hints();
>   static {
>       myApplicationSetting.put(Hints.CRS_AUTHORITY_FACTORY, 
> myOwnCrsFactory);
>       myApplicationSetting.put(Hints.CRS_GEOMETRY_FACTORY, 
> myOwnGeomFactory);
>       myApplicationSetting.put(Hints.LENIENT_DATUM_SHIFT, Boolean.TRUE);
>       myApplicationSetting.put(Hints.EPSG_DATA_SOURCE, "jdbc/MyOwnEPSG");
>       // etc.
>   }
>
>   void anyUserMethodWantingFactory() {
>       FeatureFactory f = 
> FactoryFinder.getFeatureFactory(myApplicationSetting);
>       Feature fe = f.createFoo(...);
>       // etc.
>   }
>
> The feature factory will use the user's "myOwnCrsFactory" and 
> "myOwnGeomFactory", which are propagated through the hints. A 
> different application using Geotools in the same JVM can have is own 
> application-wide setting if it define and use its own 
> "myApplicationSetting" in the same way.
>
> Note that the hints is not just about factory dependencies. It is also 
> about boolean value, name as a string, etc. In brief, everything that 
> could be specified as argument to a Factory constructor.
>
>     Martin
>