Package org.threeten.bp.chrono

Class JapaneseEra

  • All Implemented Interfaces:
    Serializable, Era, TemporalAccessor, TemporalAdjuster
    public final class JapaneseEra
extends DefaultInterfaceEra
implements Serializable
    An era in the Japanese Imperial calendar system.

    This class defines the valid eras for the Japanese chronology. Japan introduced the Gregorian calendar starting with Meiji 6. Only Meiji and later eras are supported; dates before Meiji 6, January 1 are not supported.

    The four supported eras are hard-coded. A single additional era may be registered using registerEra(LocalDate, String).

    Specification for implementors

    This class is immutable and thread-safe.
    See Also:
    Serialized Form

    • Field Detail

      • MEIJI

        public static final JapaneseEra MEIJI
        The singleton instance for the 'Meiji' era (1868-09-08 - 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.

      • REIWA

        public static final JapaneseEra REIWA
        The singleton instance for the 'Reiwa' era (2019-05-01 - current) which has the value 3.

    • Method Detail

      • registerEra

        public static JapaneseEra registerEra​(LocalDate since,
                                      String name)
        Registers an additional instance of JapaneseEra.

        A new Japanese era can begin at any time. This method allows one new era to be registered without the need for a new library version. If needed, callers should assign the result to a static variable accessible across the application. This must be done once, in early startup code.

        NOTE: This method does not exist in Java SE 8.

        Parameters:
        since - the date representing the first date of the era, validated not null
        name - the name
        Returns:
        the JapaneseEra singleton, not null
        Throws:
        DateTimeException - if an additional era has already been registered

      • of

        public static JapaneseEra of​(int japaneseEra)
        Obtains an instance of JapaneseEra from an int value.

        The SHOWA era that contains 1970-01-01 (ISO calendar system) has the value 1 Later era is numbered 2 (HEISEI). Earlier eras are numbered 0 (TAISHO), -1 (MEIJI), only Meiji and later eras are supported.

        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

      • getValue

        public int getValue()
        Returns the numeric value of this JapaneseEra.

        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) and -1 (MEIJI).

        Specified by:
        getValue in interface Era
        Returns:
        the era value

      • range

        public ValueRange range​(TemporalField field)
        Description copied from interface: TemporalAccessor
        Gets the range of valid values for the specified field.

        All fields can be expressed as a long integer. This method returns an object that describes the valid range for that value. The value of this temporal object is used to enhance the accuracy of the returned range. If the date-time cannot return the range, because the field is unsupported or for some other reason, an exception will be thrown.

        Note that the result only describes the minimum and maximum valid values and it is important not to read too much into them. For example, there could be values within the range that are invalid for the field.

        Specification for implementors

        Implementations must check and handle all fields defined in ChronoField. If the field is supported, then the range of the field must be returned. If unsupported, then a DateTimeException must be thrown.

        If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessorl) passing this as the argument.

        Implementations must not alter either this object.

        Specified by:
        range in interface TemporalAccessor
        Overrides:
        range in class DefaultInterfaceTemporalAccessor
        Parameters:
        field - the field to query the range for, not null
        Returns:
        the range of valid values for the field, not null