|For Standard||CTA v2.1|
Common has a CRS package, which has these abstract classes: AbstractProjectedCrs, AbstractVerticalCrs,and AbstractGeodeticCrs. Each of these classes has five concrete children:
- A projection identified by an EPSG code.
- A projection not known to the EPSG, which is defined using OGC’s Geographic Markup Language (GML).
- A projection that is intentionally obscured to anonymize a dataset. This is identified by a simple unvalidated string.
- A projection identified by a code according to a local authority. This would be used where a company or regulatory regime has chosen not to use EPSG codes.
- A projection identified by well-known text that complies with ISO 19162.