net.time4j.calendar

Enum JapaneseCalendar.Unit

java.lang.Object

java.lang.Enum<JapaneseCalendar.Unit>

net.time4j.calendar.JapaneseCalendar.Unit

All Implemented Interfaces:

Serializable, Comparable<JapaneseCalendar.Unit>, ChronoUnit

Enclosing class:

JapaneseCalendar

public static enum JapaneseCalendar.Unit
extends Enum<JapaneseCalendar.Unit>
implements ChronoUnit

Defines some calendar units for the Japanese calendar.

Enum Constant Summary

Enum Constants

Enum Constant and Description
DAYS Standard unit for days.
ERAS The fuzzy unit of a nengo respective era.
MONTHS The unit of a gregorian or lunisolar month.
WEEKS The Japanese calendar uses a 7-day-week.
YEARS The unit of a gregorian or lunisolar year.

Method Summary

Modifier and Type	Method and Description
long	between(JapaneseCalendar start, JapaneseCalendar end) Calculates the difference between given Japanese dates in this unit.
double	getLength() Defines the typical length of this time unit in seconds without taking into account anomalies like timezone effects or leap seconds.
boolean	isCalendrical() Queries if this time unit is calendrical respective is at least as long as a calendar day.
static JapaneseCalendar.Unit	valueOf(String name) Returns the enum constant of this type with the specified name.
static JapaneseCalendar.Unit[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

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

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

ERAS

public static final JapaneseCalendar.Unit ERAS

The fuzzy unit of a nengo respective era.

Nengos have very different and unpredictable lengths. Time4J uses Integer.MAX_VALUE as length to indicate this behaviour. If any nengo is one of the northern court (1332-1393) then it will first be converted to its southern court equivalent before applying any era arithmetics.

If necessary in case of addition, Time4J will adjust the smaller elements year-of-nengo, month-of-year and day-of-month such that they still fit within the context of the newly calculated nengo. However, the main purpose of this unit is to count the nengo distance between two Japanese dates.

YEARS

public static final JapaneseCalendar.Unit YEARS

The unit of a gregorian or lunisolar year.

Note that lunisolar years sometimes consist of 13 instead of 12 months.

MONTHS

public static final JapaneseCalendar.Unit MONTHS

The unit of a gregorian or lunisolar month.

Note: The month arithmetic is limited to amounts smaller than 25000 otherwise an ArithmeticException will be thrown.

WEEKS

public static final JapaneseCalendar.Unit WEEKS

The Japanese calendar uses a 7-day-week.

DAYS

public static final JapaneseCalendar.Unit DAYS

Standard unit for days.

See Also:

CalendarDays

Method Detail

values

public static JapaneseCalendar.Unit[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (JapaneseCalendar.Unit c : JapaneseCalendar.Unit.values())
    System.out.println(c);

Returns:

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

valueOf

public static JapaneseCalendar.Unit 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

getLength

public double getLength()

Description copied from interface: ChronoUnit

Defines the typical length of this time unit in seconds without taking into account anomalies like timezone effects or leap seconds.

Important note: This method can only yield an estimated value and is not intended to assist in calculations of durations, but only in sorting of units.

Specified by:

getLength in interface ChronoUnit

Returns:

estimated decimal value in seconds

isCalendrical

public boolean isCalendrical()

Description copied from interface: ChronoUnit

Queries if this time unit is calendrical respective is at least as long as a calendar day.

Implementation note: The method must be consistent with the typical length of the unit. The expression Double.compare(unit.getLength(), 86400.0) >= 0 is equivalent to unit.isCalendrical().

Specified by:

isCalendrical in interface ChronoUnit

Returns:

true if at least as long as a day else false

between

public long between(JapaneseCalendar start,
                    JapaneseCalendar end)

Calculates the difference between given Japanese dates in this unit.

Parameters:

start - start date (inclusive)

end - end date (exclusive)

Returns:

difference counted in this unit