Class CRSExtractorSPI

    • Constructor Detail

      • CRSExtractorSPI

        public CRSExtractorSPI()
    • Method Detail

      • isAvailable

        public boolean isAvailable()
        Description copied from interface: OptionalFactory
        Returns true if this factory is ready for use. An optional factory may returns false for now but returns true later. However, the converse is not recommended.
        Specified by:
        isAvailable in interface OptionalFactory
      • getImplementationHints

        public Map<RenderingHints.Key,​?> getImplementationHints()
        Description copied from interface: Factory
        Map of hints (maybe unmodifiable) used by this factory to customize its use. This map is not guaranteed to contains all the hints supplied by the user; it may be only a subset. Consequently, hints provided here are usually not suitable for creating new factories, unless the implementation make some additional garantees.

        The primary purpose of this method is to determine if an existing factory instance can be reused for a set of user-supplied hints. This method is invoked by FactoryRegistry in order to compare this factory's hints against user's hints. This is dependency introspection only; FactoryRegistry never invokes this method for creating new factories.

        Keys are usually static constants from the Hints class, while values are instances of some key-dependent class. The key set must contains at least all hints impacting functionality. While the key set may contains all hints supplied by the user, it is recommended to limit the set to only the hints used by this particular factory instance. A minimal set will helps FactoryRegistry to compare only hints that matter and avoid the creation of unnecessary instances of this factory.

        The hint values may be different than the one supplied by the user. If a user supplied a hint as a Class object, this method shall replace it by the actual instance used, if possible.

        Implementations of this method are usually quite simple. For example if a datum authority factory uses an ordinary datum factory, its method could be implemented as below (note that we should not check if the datum factory is null, since key with null value is the expected behaviour in this case). Example:

         Map hints = new HashMap();
         hints.put(Hints.DATUM_FACTORY, datumFactory);
         return hints;
        Specified by:
        getImplementationHints in interface Factory
        The map of hints, or an {@linkplain java.util.Collections.emptyMap() empty map} if none.