Package org.apache.sis.referencing

Enum CommonCRS.Temporal

java.lang.Object

java.lang.Enum<CommonCRS.Temporal>

org.apache.sis.referencing.CommonCRS.Temporal

All Implemented Interfaces:

Serializable, Comparable<CommonCRS.Temporal>

Enclosing class:

CommonCRS

public static enum CommonCRS.Temporal
extends Enum<CommonCRS.Temporal>

Frequently-used temporal CRS and datum that are guaranteed to be available in SIS.

Referencing objects are cached after creation. Invoking the same method on the same Temporal instance twice will return the same IdentifiedObject instance, unless the internal cache has been cleared (e.g. the application is running in a container environment and some modules have been installed or uninstalled).

Example: the following code fetches a temporal Coordinate Reference System using the Julian calendar:

Below is an alphabetical list of object names available in this enumeration. Note that the namespace of identifiers ("OGC" versus "SIS") may change in any future version.

Temporal objects accessible by enumeration constants

Name or alias	Identifier	Object type	Enumeration value
Dublin Julian	SIS:DublinJulian	CRS, Datum	DUBLIN_JULIAN
Java time	SIS:JavaTime	CRS	JAVA
Julian	OGC:JulianDate	CRS, Datum	JULIAN
Modified Julian	SIS:ModifiedJulianDate	CRS, Datum	MODIFIED_JULIAN
Truncated Julian	OGC:TruncatedJulianDate	CRS, Datum	TRUNCATED_JULIAN
Unix/POSIX time	OGC:UnixTime	CRS, Datum	UNIX

Since:

0.4

Version:

1.3

See Also:

• CommonCRS.Engineering.TIME

Enum Constant Summary

Enum Constants

Enum Constant	Description
DUBLIN_JULIAN	Time measured as days since December 31, 1899 at 12:00 UTC.
JAVA	Time measured as milliseconds since January 1st, 1970 at 00:00 UTC.
JULIAN	Time measured as days since January 1st, 4713 BC at 12:00 UTC in proleptic Julian calendar.
MODIFIED_JULIAN	Time measured as days since November 17, 1858 at 00:00 UTC.
TRUNCATED_JULIAN	Time measured as days since May 24, 1968 at 00:00 UTC.
UNIX	Time measured as seconds since January 1st, 1970 at 00:00 UTC.

Field Summary

Fields

Modifier and Type	Field	Description
private org.opengis.referencing.IdentifiedObject	cached	The cached object.
private final long	epoch	The date and time origin of this temporal datum.
private final String	identifier	Identifier in OGC or SIS namespace.
private final boolean	isOGC	Whether the identifier is in OGC namespace.
private final short	key	The resource keys for the name as one of the Vocabulary.Keys constants.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Temporal(short name, long epoch, String identifier, boolean isOGC)	Creates a new enumeration value of the given name with time counted since the given epoch.

Method Summary

Modifier and Type	Method	Description
(package private) final void	clear()	Invoked by when the cache needs to be cleared after a classpath change.
org.opengis.referencing.crs.TemporalCRS	crs()	Returns the coordinate reference system associated to this temporal object.
private static org.opengis.referencing.crs.TemporalCRS	crs(org.opengis.referencing.IdentifiedObject object)	Returns the temporal CRS associated to the given object, or null if none.
private org.opengis.referencing.cs.TimeCS	cs()	Creates the coordinate system associated to this temporal object.
org.opengis.referencing.datum.TemporalDatum	datum()	Returns the datum associated to this temporal object.
private static org.opengis.referencing.datum.TemporalDatum	datum(org.opengis.referencing.IdentifiedObject object)	Returns the datum associated to the given object, or null if none.
static CommonCRS.Temporal	forEpoch(Instant epoch)	Returns the enumeration value for the given epoch, or null if none.
static CommonCRS.Temporal	forIdentifier(String identifier, boolean onlyOGC)	Returns the enumeration value for the given identifier (without namespace).
static CommonCRS.Temporal	valueOf(String name)	Returns the enum constant of this type with the specified name.
static CommonCRS.Temporal[]	values()	Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

JULIAN

public static final CommonCRS.Temporal JULIAN

Time measured as days since January 1st, 4713 BC at 12:00 UTC in proleptic Julian calendar. This epoch is equivalent to November 24, 4714 BC when expressed in the proleptic Gregorian calendar instead of the Julian one.

Note on dates formatting: the legacy date/time formatting classes in the java.text package uses the proleptic Julian calendar for dates before October 15, 1582, while the new date/time formatting classes in the java.time.format package use the ISO-8601 calendar system, which is equivalent to the proleptic Gregorian calendar for every dates. For parsing and formatting of Julian days, the SimpleDateFormat class is closer to the common practice (but not ISO 8601 compliant).

MODIFIED_JULIAN

public static final CommonCRS.Temporal MODIFIED_JULIAN

Time measured as days since November 17, 1858 at 00:00 UTC. A Modified Julian day (MJD) is defined relative to Julian day (JD) as MJD = JD − 2400000.5.

TRUNCATED_JULIAN

public static final CommonCRS.Temporal TRUNCATED_JULIAN

Time measured as days since May 24, 1968 at 00:00 UTC. This epoch was introduced by NASA for the space program. A Truncated Julian day (TJD) is defined relative to Julian day (JD) as TJD = JD − 2440000.5.

DUBLIN_JULIAN

public static final CommonCRS.Temporal DUBLIN_JULIAN

Time measured as days since December 31, 1899 at 12:00 UTC. A Dublin Julian day (DJD) is defined relative to Julian day (JD) as DJD = JD − 2415020.

UNIX

public static final CommonCRS.Temporal UNIX

Time measured as seconds since January 1st, 1970 at 00:00 UTC.

JAVA

public static final CommonCRS.Temporal JAVA

Time measured as milliseconds since January 1st, 1970 at 00:00 UTC.

Field Details

key

private final short key

The resource keys for the name as one of the Vocabulary.Keys constants.

epoch

private final long epoch

The date and time origin of this temporal datum.

identifier

private final String identifier

Identifier in OGC or SIS namespace.

See Also:

• CommonAuthorityFactory.TEMPORAL_NAMES

isOGC

private final boolean isOGC

Whether the identifier is in OGC namespace.

cached

private transient volatile org.opengis.referencing.IdentifiedObject cached

The cached object. This is initially null, then set to various kinds of objects depending on which method has been invoked. The kind of object stored in this field may change during the application execution.

Constructor Details

Temporal

private Temporal(short name,
 long epoch,
 String identifier,
 boolean isOGC)

Creates a new enumeration value of the given name with time counted since the given epoch.

Method Details

values

public static CommonCRS.Temporal[] values()

Returns an array containing the constants of this enum type, in the order they are declared.

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static CommonCRS.Temporal valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

clear

final void clear()

Invoked by when the cache needs to be cleared after a classpath change.

forIdentifier

public static CommonCRS.Temporal forIdentifier(String identifier,
 boolean onlyOGC)

Returns the enumeration value for the given identifier (without namespace). Identifiers in OGC namespace are "JulianDate", "TruncatedJulianDate" and "UnixTime". Identifiers in SIS namespace are "ModifiedJulianDate", "DublinJulian" and "JavaTime". Note that the content of OGC and SIS namespaces may change in any future version.

Parameters:

identifier - case-insensitive identifier of the desired temporal CRS, without namespace.

onlyOGC - whether to return the CRS only if its identifier is in OGC namespace.

Returns:

the enumeration value for the given identifier.

Throws:

IllegalArgumentException - if the given identifier is not recognized.

Since:

1.3

See Also:

• OGC Definitions Server

forEpoch

@OptionalCandidate
public static CommonCRS.Temporal forEpoch(Instant epoch)

Returns the enumeration value for the given epoch, or null if none. If the epoch is January 1st, 1970, then this method returns UNIX.

Parameters:

epoch - the epoch for which to get an enumeration value, or null.

Returns:

the enumeration value for the given epoch, or null if none.

Since:

1.0

crs

public org.opengis.referencing.crs.TemporalCRS crs()

Returns the coordinate reference system associated to this temporal object. The following table summarizes the CRS known to this class, together with an enumeration value that can be used for fetching that CRS:

Commonly used temporal CRS

Name or alias	Enum
Dublin Julian	DUBLIN_JULIAN
Julian	JULIAN
Modified Julian	MODIFIED_JULIAN
Truncated Julian	TRUNCATED_JULIAN
Unix/POSIX	UNIX
Java Date	JAVA

Returns:

the CRS associated to this enum.

See Also:

• DefaultTemporalCRS

cs

private org.opengis.referencing.cs.TimeCS cs()

Creates the coordinate system associated to this temporal object. This method does not cache the coordinate system.

datum

public org.opengis.referencing.datum.TemporalDatum datum()

Returns the datum associated to this temporal object. The following table summarizes the datum known to this class, together with an enumeration value that can be used for fetching that datum:

Commonly used temporal datum

Name or alias	Enum
Dublin Julian	DUBLIN_JULIAN
Julian	JULIAN
Modified Julian	MODIFIED_JULIAN
Truncated Julian	TRUNCATED_JULIAN
Unix/POSIX or Java	UNIX

Returns:

the datum associated to this enum.

See Also:

• DefaultTemporalDatum

crs

private static org.opengis.referencing.crs.TemporalCRS crs(org.opengis.referencing.IdentifiedObject object)

Returns the temporal CRS associated to the given object, or null if none.

datum

private static org.opengis.referencing.datum.TemporalDatum datum(org.opengis.referencing.IdentifiedObject object)

Returns the datum associated to the given object, or null if none.