Hello all
There is a quick update on current work:
"IdentifiedObject" is a type defined by the ISO 19111 specification.
"AbstractIdentifiedObject" [1] is the proposed SIS implementation. This
class is intended to be the base class of almost everything related to
Coordinate Reference System (GeographicCRS, ProjectedCRS, etc.). For
this reason, it would be an important class of SIS.
The problem that "IdentifiedObject" tries to resolve is that the same
map projections are often known by different names and identifiers
depending on the providers. For example "Oblique Mercator" and "Hotine
Oblique Mercator" (in EPSG naming) are two different projections. But
"Oblique Mercator" (not Hotine) in EPSG naming is also called "Hotine
Oblique Mercator Azimuth Center" by ESRI, while "Hotine Oblique
Mercator" (EPSG naming) is called "Hotine Oblique Mercator Azimuth
Natural Origin" by ESRI. In summary, it is not sufficient to know the
name of a map projection. We also need to know who chosen that name (the
"authority").
So IdentifiedObject manages:
* A primary name (whatever SIS chooses as our preferred naming)
* An arbitrary amount of aliases, together with their authorities
* An arbitrary amount of identifiers, typically primary keys in a
database (e.g. "EPSG:4326"), again with the authority that defines
each identifier.
Martin
[1]
https://builds.apache.org/job/sis-jdk7/site/apidocs/org/apache/sis/referencing/AbstractIdentifiedObject.html
