- All Implemented Interfaces:
Serializable
,Era
,TemporalAccessor
,TemporalAdjuster
public final class JapaneseEra extends Object implements Era, Serializable
The Japanese government defines the official name and start date of each era. Eras are consecutive and their date ranges do not overlap, so the end date of one era is always the day before the start date of the next era.
The Java SE Platform supports all eras defined by the Japanese government,
beginning with the Meiji era. Each era is identified in the Platform by an
integer value and a name. The of(int)
and valueOf(String)
methods may be used to obtain a singleton instance of JapaneseEra
for each era. The values()
method returns the singleton instances
of all supported eras.
For convenience, this class declares a number of public static final fields
that refer to singleton instances returned by the values()
method.
- API Note:
- The fields declared in this class may evolve over time, in line with the
results of the
values()
method. However, there is not necessarily a 1:1 correspondence between the fields and the singleton instances., The Japanese government may announce a new era and define its start date but not its official name. In this scenario, the singleton instance that represents the new era may return a name that is not stable until the official name is defined. Developers should exercise caution when relying on the name returned by any singleton instance that does not correspond to a public static final field. - Implementation Requirements:
- This class is immutable and thread-safe.
- Since:
- 1.8
- See Also:
- Serialized Form
-
Field Summary
Fields Modifier and Type Field Description static JapaneseEra
HEISEI
The singleton instance for the 'Heisei' era (1989-01-08 - 2019-04-30) which has the value 2.static JapaneseEra
MEIJI
The singleton instance for the 'Meiji' era (1868-01-01 - 1912-07-29) which has the value -1.static JapaneseEra
REIWA
The singleton instance for the 'Reiwa' era (2019-05-01 - ) which has the value 3.static JapaneseEra
SHOWA
The singleton instance for the 'Showa' era (1926-12-25 - 1989-01-07) which has the value 1.static JapaneseEra
TAISHO
The singleton instance for the 'Taisho' era (1912-07-30 - 1926-12-24) which has the value 0. -
Method Summary
Modifier and Type Method Description String
getDisplayName(TextStyle style, Locale locale)
Gets the textual representation of this era.int
getValue()
Gets the numeric eraint
value.static JapaneseEra
of(int japaneseEra)
Obtains an instance ofJapaneseEra
from anint
value.ValueRange
range(TemporalField field)
Gets the range of valid values for the specified field.static JapaneseEra
valueOf(String japaneseEra)
Returns theJapaneseEra
with the name.static JapaneseEra[]
values()
Returns an array of JapaneseEras.Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods declared in interface java.time.chrono.Era
adjustInto, get, getLong, isSupported, query
-
Field Details
-
MEIJI
The singleton instance for the 'Meiji' era (1868-01-01 - 1912-07-29) which has the value -1. -
TAISHO
The singleton instance for the 'Taisho' era (1912-07-30 - 1926-12-24) which has the value 0. -
SHOWA
The singleton instance for the 'Showa' era (1926-12-25 - 1989-01-07) which has the value 1. -
HEISEI
The singleton instance for the 'Heisei' era (1989-01-08 - 2019-04-30) which has the value 2. -
REIWA
The singleton instance for the 'Reiwa' era (2019-05-01 - ) which has the value 3. The end date of this era is not specified, unless the Japanese Government defines it.- Since:
- 13
-
-
Method Details
-
of
Obtains an instance ofJapaneseEra
from anint
value.- The value
1
is associated with the 'Showa' era, because it contains 1970-01-01 (ISO calendar system). - The values
-1
and0
are associated with two earlier eras, Meiji and Taisho, respectively. - A value greater than
1
is associated with a later era, beginning with Heisei (2
).
Every instance of
JapaneseEra
that is returned from thevalues()
method has an int value (available viaEra.getValue()
which is accepted by this method.- Parameters:
japaneseEra
- the era to represent- Returns:
- the
JapaneseEra
singleton, not null - Throws:
DateTimeException
- if the value is invalid
- The value
-
valueOf
Returns theJapaneseEra
with the name.The string must match exactly the name of the era. (Extraneous whitespace characters are not permitted.)
Valid era names are the names of eras returned from
values()
.- Parameters:
japaneseEra
- the japaneseEra name; non-null- Returns:
- the
JapaneseEra
singleton, never null - Throws:
IllegalArgumentException
- if there is not JapaneseEra with the specified name
-
values
Returns an array of JapaneseEras. The array may contain eras defined by the Japanese government beyond the known era singletons.This method may be used to iterate over the JapaneseEras as follows:
for (JapaneseEra c : JapaneseEra.values()) System.out.println(c);
- Returns:
- an array of JapaneseEras
-
getDisplayName
Gets the textual representation of this era.This returns the textual name used to identify the era, suitable for presentation to the user. The parameters control the style of the returned text and the locale.
If no textual mapping is found then the
numeric value
is returned.- Specified by:
getDisplayName
in interfaceEra
- Parameters:
style
- the style of the text required, not nulllocale
- the locale to use, not null- Returns:
- the text value of the era, not null
-
getValue
public int getValue() -
range
Gets the range of valid values for the specified field.The range object expresses the minimum and maximum valid values for a field. This era is used to enhance the accuracy of the returned range. If it is not possible to return the range, because the field is not supported or for some other reason, an exception is thrown.
If the field is a
ChronoField
then the query is implemented here. TheERA
field returns the range. All otherChronoField
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.rangeRefinedBy(TemporalAccessor)
passingthis
as the argument. Whether the range can be obtained is determined by the field.The range of valid Japanese eras can change over time due to the nature of the Japanese calendar system.
- Specified by:
range
in interfaceEra
- Specified by:
range
in interfaceTemporalAccessor
- Parameters:
field
- the field to query the range for, not null- Returns:
- the range of valid values for the field, not null
- Throws:
DateTimeException
- if the range for the field cannot be obtainedUnsupportedTemporalTypeException
- if the unit is not supported
-