agi.foundation.time

(agi.foundation.core-2025r1.jar)

Class TimeStandard

java.lang.Object

agi.foundation.time.TimeStandard

All Implemented Interfaces:

IIndexedFormat

public class TimeStandard
extends Object
implements IIndexedFormat

Provides a means for measuring time by specifying the rate at which time passes and/or points in time. Note that for many operations, the system will need to convert times to an ArithmeticSafeStandard (get) in order to correctly compare times. In many cases, it may be more efficient to work directly in the corresponding ArithmeticSafeStandard (get).

Constructor Summary

Constructors

Constructor and Description
TimeStandard(String name, String abbreviation, TimeStandard arithmeticSafeStandard) Initializes a new instance.

Method Summary

Modifier and Type	Method and Description
String	getAbbreviation() Gets an abbreviation for this time standard.
TimeStandard	getArithmeticSafeStandard() Gets a time standard that is equivalent to this time standard but is safe for arithmetic.
static TimeStandard	getBarycentricDynamicalTime() Gets the Barycentric Dynamical Time (TDB) time standard.
static TimeStandard	getCoordinatedUniversalTime() Gets the Coordinated Universal Time (UTC) time standard.
static TimeStandard	getGlobalPositioningSystemTime() Gets the Global Positioning System (GPS) time standard.
int	getIndex() Gets the index corresponding to this time standard.
static TimeStandard	getInternationalAtomicTime() Gets the International Atomic Time (TAI) time standard.
String	getName() Gets the name of this time standard.
static TimeStandard	getTerrestrialTime() Gets the Terrestrial Time (TT) time standard.
static TimeStandard	getUniversalTime1() Gets the Universal Time 1 (UT1) time standard.
String	toString() Converts this time standard to a string representation.

Methods inherited from class java.lang.Object

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

Constructor Detail

TimeStandard

public TimeStandard(@Nonnull
                    String name,
                    @Nonnull
                    String abbreviation,
                    @Nullable
                    TimeStandard arithmeticSafeStandard)

Initializes a new instance.

Parameters:

name - The name of the time standard.

abbreviation - An abbreviation for the time standard.

arithmeticSafeStandard - Another time standard that is closely related to this one but is safe for arithmetic, or null if this standard is itself safe for arithmetic.

Throws:

ArgumentNullException - Thrown when name or abbreviation is null.

Method Detail

getInternationalAtomicTime

@Nonnull
public static TimeStandard getInternationalAtomicTime()

Gets the International Atomic Time (TAI) time standard.

TAI is the principal time standard to which the other time standards are related.

getTerrestrialTime

@Nonnull
public static TimeStandard getTerrestrialTime()

Gets the Terrestrial Time (TT) time standard.

TT is related to TAI according to the relationship TT = TAI + 32.184 seconds.

getBarycentricDynamicalTime

@Nonnull
public static TimeStandard getBarycentricDynamicalTime()

Gets the Barycentric Dynamical Time (TDB) time standard.

TDB is related to TT according to the relationship TDB = TT + deltaT, where deltaT is the difference due to time dilation and is determined according to equation (2.222-1) on page 42 of Seidelmann, P. Kenneth, ed. "Explanatory Supplement to the Astronomical Almanac". Mill Valley, CA: University Science Books, 1992.

getCoordinatedUniversalTime

@Nonnull
public static TimeStandard getCoordinatedUniversalTime()

Gets the Coordinated Universal Time (UTC) time standard.

UTC is related to TAI according to the relationship UTC = TAI - deltaT, where deltaT is the number of leap seconds which have been introduced as of the time in TAI.

getGlobalPositioningSystemTime

@Nonnull
public static TimeStandard getGlobalPositioningSystemTime()

Gets the Global Positioning System (GPS) time standard.

GPS is related to TAI according to the relationship GPS = TAI - 19.0 seconds.

getUniversalTime1

@Nonnull
public static TimeStandard getUniversalTime1()

Gets the Universal Time 1 (UT1) time standard.

UT1 is related to UTC according to the relationship UT1 = UTC + deltaT, where deltaT is a correction interpolated at the time in UTC from the Earth orientation parameters.

getName

@Nonnull
public final String getName()

Gets the name of this time standard.

getAbbreviation

@Nonnull
public final String getAbbreviation()

Gets an abbreviation for this time standard.

getArithmeticSafeStandard

@Nullable
public final TimeStandard getArithmeticSafeStandard()

Gets a time standard that is equivalent to this time standard but is safe for arithmetic. In order to be safe for arithmetic, a time standard must not have any discontinuities, and it must have exactly 86400 seconds in every day. How the seconds are measured does not matter, but the standard returned by this method must measure seconds in the same way as the standard implementing this method. For example, CoordinatedUniversalTime (get) is not safe for arithmetic (and thus returns InternationalAtomicTime (get)) but UniversalTime1 (get) is safe for arithmetic. If a time standard is safe for arithmetic, returns null.

getIndex

public final int getIndex()

Gets the index corresponding to this time standard.

Specified by:

getIndex in interface IIndexedFormat

toString

public String toString()

Converts this time standard to a string representation.

Overrides:

toString in class Object

Returns:

The string.