Class AbstractReferenceSystem

All Implemented Interfaces:
Serializable, Formattable, Deprecable, Lenient­Comparable, Identified­Object, Reference­System
Direct Known Subclasses:
Abstract­CRS, Referencing­By­Identifiers

public class AbstractReferenceSystem extends AbstractIdentifiedObject implements ReferenceSystem
Description of a spatial and temporal reference system used by a dataset. Reference systems do not necessarily use coordinates. For example a reference system could use postal codes. The specialized case of referencing by coordinates is handled by the Abstract­CRS subclass.

This class inherits the name, aliases, identifiers and remarks from the parent class, and adds the following information:

  • a domain of validity, the area for which the reference system is valid,
  • a scope, which describes the domain of usage or limitation of usage.


This class is conceptually abstract, even if it is technically possible to instantiate it. Typical applications should create instances of the most specific subclass prefixed by Default instead.

Immutability and thread safety

This base class is immutable and thus thread-safe if the property values (not necessarily the map itself) given to the constructor are also immutable. Most SIS subclasses and related classes are immutable under similar conditions. This means that unless otherwise noted in the javadoc, Reference­System instances created using only SIS factories and static constants can be shared by many objects and passed between threads without synchronization.
See Also:

Defined in the sis-referencing module