Class JapaneseEra
- java.lang.Object
-
- java.time.chrono.JapaneseEra
- All Implemented Interfaces:
-
Serializable
,Era
,TemporalAccessor
,TemporalAdjuster
public final class JapaneseEra extends Object implements Era, Serializable
An era in the Japanese Imperial calendar system.
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
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 | 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 era |
static JapaneseEra | of(int japaneseEra) | Obtains an instance of |
ValueRange | range(TemporalField field) | Gets the range of valid values for the specified field. |
static JapaneseEra | valueOf(String japaneseEra) | Returns the |
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 Detail
MEIJI
public static final JapaneseEra MEIJI
The singleton instance for the 'Meiji' era (1868-01-01 - 1912-07-29) which has the value -1.
TAISHO
public static final JapaneseEra TAISHO
The singleton instance for the 'Taisho' era (1912-07-30 - 1926-12-24) which has the value 0.
SHOWA
public static final JapaneseEra SHOWA
The singleton instance for the 'Showa' era (1926-12-25 - 1989-01-07) which has the value 1.
HEISEI
public static final JapaneseEra HEISEI
The singleton instance for the 'Heisei' era (1989-01-08 - 2019-04-30) which has the value 2.
Method Detail
of
public static JapaneseEra of(int japaneseEra)
Obtains an instance of JapaneseEra
from an int
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 the values()
method has an int value (available via Era.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
valueOf
public static JapaneseEra valueOf(String japaneseEra)
Returns the JapaneseEra
with the name.
The string must match exactly the name of the era. (Extraneous whitespace characters are not permitted.)
- 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
public static JapaneseEra[] values()
Returns an array of JapaneseEras.
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
public String getDisplayName(TextStyle style, Locale locale)
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 null -
locale
- the locale to use, not null - Returns:
- the text value of the era, not null
getValue
public int getValue()
Gets the numeric era int
value.
The SHOWA
era that contains 1970-01-01 (ISO calendar system) has the value 1. Later eras are numbered from 2 (HEISEI
). Earlier eras are numbered 0 (TAISHO
), -1 (MEIJI
)).
range
public ValueRange range(TemporalField field)
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. The ERA
field returns the range. All other ChronoField
instances will throw an UnsupportedTemporalTypeException
.
If the field is not a ChronoField
, then the result of this method is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessor)
passing this
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 obtained -
UnsupportedTemporalTypeException
- if the unit is not supported