net.time4j.calendar.astro

Class Zodiac.Event

java.lang.Object

net.time4j.calendar.astro.Zodiac.Event

All Implemented Interfaces:

Predicate<Moment>, ChronoCondition<Moment>

Enclosing class:

Zodiac

public static class Zodiac.Event
extends Object
implements ChronoCondition<Moment>

Represents the event when the sun or moon enters or exits a zodiac.

Since:

4.37

Author:

Meno Hochschild

See Also:

SunPosition.inSignOf(Zodiac), MoonPosition.inSignOf(Zodiac), SunPosition.inConstellationOf(Zodiac), MoonPosition.inConstellationOf(Zodiac)

Method Summary

Modifier and Type	Method and Description
Moment	atMomentOfEntry(Moment start) Calculates the moment when the celestial body enters the associated zodiac.
Moment	atMomentOfExit(Moment start) Calculates the moment when the celestial body leaves the associated zodiac.
boolean	test(Moment moment) Tests if this event happens at given moment.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.function.Predicate

and, isEqual, negate, or

Method Detail

atMomentOfEntry

public Moment atMomentOfEntry(Moment start)

Calculates the moment when the celestial body enters the associated zodiac.

The accuracy is limited to roughly minute precision.

Parameters:

start - the moment when to start the search

Returns:

moment of this event at or after given start

Throws:

IllegalArgumentException - if the Julian day of moment is not in supported range

atMomentOfExit

public Moment atMomentOfExit(Moment start)

Calculates the moment when the celestial body leaves the associated zodiac.

The accuracy is limited to roughly minute precision.

Parameters:

start - the moment when to start the search

Returns:

moment of this event at or after given start

Throws:

IllegalArgumentException - if the Julian day of moment is not in supported range

test

public boolean test(Moment moment)

Tests if this event happens at given moment.

Example of usage:

     Moment moment = PlainTimestamp.of(2000, 4, 18, 13, 16).atUTC();
     System.out.println(moment.matches(SunPosition.inConstellationOf(Zodiac.ARIES))); // true
 

Note: Due to precessional effects, Aries is nowadays passed by sun in April and not around vernal equinox as 2000 years ago.

Specified by:

test in interface Predicate<Moment>

Specified by:

test in interface ChronoCondition<Moment>

Parameters:

moment - the moment to be tested

Returns:

boolean