Module org.apache.sis.referencing

Package org.apache.sis.referencing.factory

Class CommonAuthorityFactory

Object

AbstractFactory

GeodeticAuthorityFactory

CommonAuthorityFactory

All Implemented Interfaces:

Authority­Factory, CRSAuthority­Factory, Factory

public class CommonAuthorityFactory
extends GeodeticAuthorityFactory
implements CRSAuthorityFactory

Creates coordinate reference systems in the "OGC", "CRS" or "AUTO(2)" namespaces. All namespaces recognized by this factory are defined by the Open Geospatial Consortium (OGC). Most codes map to one of the constants in the Common­CRS enumeration.

Recognized Coordinate Reference System codes

Namespace	Code	Name	Datum type	CS type	Axis direction	Units
CRS	1	Computer display	Engineering	Cartesian	(east, south)	pixels
CRS	27	NAD27	Geographic	Ellipsoidal	(east, north)	degrees
CRS	83	NAD83	Geographic	Ellipsoidal	(east, north)	degrees
CRS	84	WGS84	Geographic	Ellipsoidal	(east, north)	degrees
CRS	88	NAVD88	Vertical	Vertical	up	metres
AUTO2	42001	WGS 84 / Auto UTM	Projected	Cartesian	(east, north)	user-specified
AUTO2	42002	WGS 84 / Auto Tr Mercator	Projected	Cartesian	(east, north)	user-specified
AUTO2	42003	WGS 84 / Auto Orthographic	Projected	Cartesian	(east, north)	user-specified
AUTO2	42004	WGS 84 / Auto Equirectangular	Projected	Cartesian	(east, north)	user-specified
AUTO2	42005	WGS 84 / Auto Mollweide	Projected	Cartesian	(east, north)	user-specified
OGC	JulianDate	Julian	Temporal	Time	(future)	days
OGC	TruncatedJulianDate	Truncated Julian	Temporal	Time	(future)	days
OGC	UnixTime	Unix Time	Temporal	Time	(future)	seconds

Note on codes in CRS namespace

The format is usually "CRS:n" where n is a number like 27, 83 or 84. However, this factory is lenient and allows the CRS part to be repeated as in "CRS:CRS84". It also accepts "OGC" as a synonymous of the "CRS" namespace.

Examples: "CRS:27", "CRS:83", "CRS:84", "CRS:CRS84", "OGC:CRS84".

Note on codes in AUTO(2) namespace

The format is usually "AUTO2:n,factor,λ₀,φ₀" where n is a number between 42001 and 42005 inclusive, factor is a conversion factor from the CRS units to metres (e.g. 0.3048 for a CRS with axes in feet) and (λ₀,φ₀) is the longitude and latitude of a point in the projection centre.

Examples: "AUTO2:42001,1,-100,45" identifies a Universal Transverse Mercator (UTM) projection for a zone containing the point at (45°N, 100°W) with axes in metres.

Codes in the "AUTO" namespace are the same than codes in the "AUTO2" namespace, except that the EPSG code of the desired unit of measurement was used instead of the unit factor. The "AUTO" namespace was defined in the Web Map Service (WMS) 1.1.1 specification while the "AUTO2" namespace is defined in WMS 1.3.0. In Apache SIS implementation, the unit parameter (either as factor or as EPSG code) is optional and defaults to metres.

In the AUTO(2):42001 case, the UTM zone is calculated as specified in WMS 1.3 specification, i.e. without taking in account the Norway and Svalbard special cases and without switching to polar stereographic projections for high latitudes.

Since:

0.7

See Also:

• Common­CRS

Constructor Summary

Constructors

Constructor	Description
Common­Authority­Factory()	Constructs a default factory for the CRS authority.

Method Summary

Modifier and Type	Method	Description
Coordinate­Reference­System	create­Coordinate­Reference­System(String code)	Creates a coordinate reference system from the specified code.
Identified­Object	create­Object(String code)	Creates an object from the specified code.
Citation	get­Authority()	Returns the specification that defines the codes recognized by this factory.
Set<String>	get­Authority­Codes(Class<? extends Identified­Object> type)	Provides a complete set of the known codes provided by this factory.
Set<String>	get­Code­Spaces()	Returns the namespaces defined by the OGC specifications implemented by this factory.
International­String	get­Description­Text(String code)	Returns a description of the object corresponding to a code.

Methods inherited from class GeodeticAuthorityFactory

create­Cartesian­CS, create­Compound­CRS, create­Coordinate­Operation, create­Coordinate­System, create­Coordinate­System­Axis, create­Cylindrical­CS, create­Datum, create­Derived­CRS, create­Ellipsoid, create­Ellipsoidal­CS, create­Engineering­CRS, create­Engineering­Datum, create­Extent, create­From­Coordinate­Reference­System­Codes, create­Geocentric­CRS, create­Geodetic­Datum, create­Geographic­CRS, create­Image­CRS, create­Image­Datum, create­Operation­Method, create­Parameter­Descriptor, create­Parametric­CRS, create­Parametric­CS, create­Parametric­Datum, create­Polar­CS, create­Prime­Meridian, create­Projected­CRS, create­Spherical­CS, create­Temporal­CRS, create­Temporal­Datum, create­Time­CS, create­Unit, create­Vertical­CRS, create­Vertical­CS, create­Vertical­Datum, new­Identified­Object­Finder, to­String, trim­Namespace

Methods inherited from class AbstractFactory

get­Vendor

Methods inherited from class Object

clone, equals, finalize, get­Class, hash­Code, notify, notify­All, wait, wait, wait

Methods inherited from interface CRSAuthorityFactory

create­Compound­CRS, create­Derived­CRS, create­Engineering­CRS, create­Geocentric­CRS, create­Geographic­CRS, create­Image­CRS, create­Projected­CRS, create­Temporal­CRS, create­Vertical­CRS

Methods inherited from interface Factory

get­Vendor

Constructor Details

CommonAuthorityFactory

public CommonAuthorityFactory()

Constructs a default factory for the CRS authority.

Method Details

getAuthority

public Citation getAuthority()

Returns the specification that defines the codes recognized by this factory. The definitive source for this factory is OGC Web Map Service (WMS) specification, also available as the ISO 19128 Geographic Information — Web map server interface standard.

While the authority is WMS, the namespace of that authority is set to "OGC". Apache SIS does that for consistency with the namespace used in URNs (for example "urn:ogc:def:crs:OGC:1.3:CRS84").

Specified by:

get­Authority in interface Authority­Factory

Specified by:

get­Authority in class Geodetic­Authority­Factory

Returns:

the "Web Map Service" authority.

See Also:

• get­Code­Spaces()
• Citations.WMS

getAuthorityCodes

public Set<String> getAuthorityCodes(Class<? extends IdentifiedObject> type)
                              throws FactoryException

Provides a complete set of the known codes provided by this factory. The returned set contains a namespace followed by identifiers like "CRS:84", "CRS:27", "AUTO2:42001", etc.

Specified by:

get­Authority­Codes in interface Authority­Factory

Parameters:

type - the spatial reference objects type.

Returns:

the set of authority codes for spatial reference objects of the given type.

Throws:

Factory­Exception - if this method failed to provide the set of codes.

getCodeSpaces

public Set<String> getCodeSpaces()

Returns the namespaces defined by the OGC specifications implemented by this factory. At the difference of other factories, the namespaces of Common­Authority­Factory are quite different than the authority title or identifier:

• Authority: "WMS" (for "Web Map Services")
• Namespaces: "CRS", "AUTO", "AUTO2". The "OGC" namespace is also accepted for compatibility reason, but its scope is wider than the above-cited namespaces.

Overrides:

get­Code­Spaces in class Geodetic­Authority­Factory

Returns:

a set containing at least the "CRS", "AUTO" and "AUTO2" strings.

See Also:

• get­Authority()
• Citations.WMS

getDescriptionText

public InternationalString getDescriptionText(String code)
                                       throws FactoryException

Returns a description of the object corresponding to a code. The description can be used for example in a combo box in a graphical user interface.

Codes in the "AUTO(2)" namespace do not need parameters for this method. But if parameters are nevertheless specified, then they will be taken in account.

Examples

Argument value	Return value
CRS:84	WGS 84
AUTO2:42001	WGS 84 / Auto UTM
AUTO2:42001,1,-100,45	WGS 84 / UTM zone 47N

Specified by:

get­Description­Text in interface Authority­Factory

Overrides:

get­Description­Text in class Geodetic­Authority­Factory

Parameters:

code - value in the CRS or AUTO(2) code space.

Returns:

a description of the object.

Throws:

No­Such­Authority­Code­Exception - if the specified code was not found.

Factory­Exception - if an error occurred while fetching the description.

createObject

public IdentifiedObject createObject(String code)
                              throws FactoryException

Creates an object from the specified code. The default implementation delegates to create­Coordinate­Reference­System(String).

Specified by:

create­Object in interface Authority­Factory

Specified by:

create­Object in class Geodetic­Authority­Factory

Parameters:

code - value allocated by authority.

Returns:

the object for the given code.

Throws:

Factory­Exception - if the object creation failed.

See Also:

• Abstract­Identified­Object

createCoordinateReferenceSystem

public CoordinateReferenceSystem createCoordinateReferenceSystem(String code)
                                                          throws FactoryException

Creates a coordinate reference system from the specified code. This method performs the following steps:

1. Skip the "OGC", "CRS", "AUTO", "AUTO1" or "AUTO2" namespace if present (ignoring case). All other namespaces will cause an exception to be thrown.
2. Skip the "CRS" prefix if present. This additional check is for accepting codes like "OGC:CRS84" (not a valid CRS code, but seen in practice).
3. In the remaining text, interpret the integer value as documented in this class javadoc. Note that some codes require coma-separated parameters after the integer value.

Specified by:

create­Coordinate­Reference­System in interface CRSAuthority­Factory

Overrides:

create­Coordinate­Reference­System in class Geodetic­Authority­Factory

Parameters:

code - value allocated by OGC.

Returns:

the coordinate reference system for the given code.

Throws:

Factory­Exception - if the object creation failed.

See Also:

• Abstract­CRS
• CRS.for­Code(String)