Added in API level 26

TemporalField

interface TemporalField

java.time.temporal.TemporalField

Known Direct Subclasses

ChronoField

A standard set of fields.

Known Indirect Subclasses

ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH, ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR, ChronoField.ALIGNED_WEEK_OF_MONTH, ChronoField.ALIGNED_WEEK_OF_YEAR, ChronoField.AMPM_OF_DAY, ChronoField.CLOCK_HOUR_OF_AMPM, ChronoField.CLOCK_HOUR_OF_DAY, ChronoField.DAY_OF_MONTH, ChronoField.DAY_OF_WEEK, ChronoField.DAY_OF_YEAR, ChronoField.EPOCH_DAY, ChronoField.ERA, and 18 others.

ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH	The aligned day-of-week within a month.
ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR	The aligned day-of-week within a year.
ChronoField.ALIGNED_WEEK_OF_MONTH	The aligned week within a month.
ChronoField.ALIGNED_WEEK_OF_YEAR	The aligned week within a year.
ChronoField.AMPM_OF_DAY	The am-pm-of-day.
ChronoField.CLOCK_HOUR_OF_AMPM	The clock-hour-of-am-pm.
ChronoField.CLOCK_HOUR_OF_DAY	The clock-hour-of-day.
ChronoField.DAY_OF_MONTH	The day-of-month.
ChronoField.DAY_OF_WEEK	The day-of-week, such as Tuesday.
ChronoField.DAY_OF_YEAR	The day-of-year.
ChronoField.EPOCH_DAY	The epoch-day, based on the Java epoch of 1970-01-01 (ISO).
ChronoField.ERA	The era.
ChronoField.HOUR_OF_AMPM	The hour-of-am-pm.
ChronoField.HOUR_OF_DAY	The hour-of-day.
ChronoField.INSTANT_SECONDS	The instant epoch-seconds.
ChronoField.MICRO_OF_DAY	The micro-of-day.
ChronoField.MICRO_OF_SECOND	The micro-of-second.
ChronoField.MILLI_OF_DAY	The milli-of-day.
ChronoField.MILLI_OF_SECOND	The milli-of-second.
ChronoField.MINUTE_OF_DAY	The minute-of-day.
ChronoField.MINUTE_OF_HOUR	The minute-of-hour.
ChronoField.MONTH_OF_YEAR	The month-of-year, such as March.
ChronoField.NANO_OF_DAY	The nano-of-day.
ChronoField.NANO_OF_SECOND	The nano-of-second.
ChronoField.OFFSET_SECONDS	The offset from UTC/Greenwich.
ChronoField.PROLEPTIC_MONTH	The proleptic-month based, counting months sequentially from year 0.
ChronoField.SECOND_OF_DAY	The second-of-day.
ChronoField.SECOND_OF_MINUTE	The second-of-minute.
ChronoField.YEAR	The proleptic year, such as 2012.
ChronoField.YEAR_OF_ERA	The year within the era.

A field of date-time, such as month-of-year or minute-of-hour.

Date and time is expressed using fields which partition the time-line into something meaningful for humans. Implementations of this interface represent those fields.

The most commonly used units are defined in ChronoField. Further fields are supplied in IsoFields, WeekFields and JulianFields. Fields can also be written by application code by implementing this interface.

The field works using double dispatch. Client code calls methods on a date-time like LocalDateTime which check if the field is a ChronoField. If it is, then the date-time must handle it. Otherwise, the method call is re-dispatched to the matching method in this interface.

Summary

Public methods
abstract R	`adjustInto(temporal: R, newValue: Long)` Returns a copy of the specified temporal object with the value of this field set.
abstract TemporalUnit!	`getBaseUnit()` Gets the unit that the field is measured in.
open String!	`getDisplayName(locale: Locale!)` Gets the display name for the field in the requested locale.
abstract Long	`getFrom(temporal: TemporalAccessor!)` Gets the value of this field from the specified temporal object.
abstract TemporalUnit!	`getRangeUnit()` Gets the range that the field is bound by.
abstract Boolean	`isDateBased()` Checks if this field represents a component of a date.
abstract Boolean	`isSupportedBy(temporal: TemporalAccessor!)` Checks if this field is supported by the temporal object.
abstract Boolean	`isTimeBased()` Checks if this field represents a component of a time.
abstract ValueRange!	`range()` Gets the range of valid values for the field.
abstract ValueRange!	`rangeRefinedBy(temporal: TemporalAccessor!)` Get the range of valid values for this field using the temporal object to refine the result.
open TemporalAccessor!	`resolve(fieldValues: MutableMap<TemporalField!, Long!>!, partialTemporal: TemporalAccessor!, resolverStyle: ResolverStyle!)` Resolves this field to provide a simpler alternative or a date.

Public methods

adjustInto

Added in API level 26

abstract fun <R : Temporal!> adjustInto(
    temporal: R, 
    newValue: Long
): R

Returns a copy of the specified temporal object with the value of this field set.

This returns a new temporal object based on the specified one with the value for this field changed. For example, on a LocalDate, this could be used to set the year, month or day-of-month. The returned object has the same observable type as the specified object.

In some cases, changing a field is not fully defined. For example, if the target object is a date representing the 31st January, then changing the month to February would be unclear. In cases like this, the implementation is responsible for resolving the result. Typically it will choose the previous valid date, which would be the last valid day of February in this example.

There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use Temporal#with(TemporalField, long):

// these two lines are equivalent, but the second approach is recommended
    temporal = thisField.adjustInto(temporal);
    temporal = temporal.with(thisField);

It is recommended to use the second approach, with(TemporalField), as it is a lot clearer to read in code.

Implementations should perform any queries or calculations using the fields available in ChronoField. If the field is not supported an UnsupportedTemporalTypeException must be thrown.

Implementations must not alter the specified temporal object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.

Parameters
`<R>`	the type of the Temporal object
`temporal`	R: the temporal object to adjust, not null
`newValue`	Long: the new value of the field

Return
`R`	the adjusted temporal object, not null

Exceptions
`java.time.DateTimeException`	if the field cannot be set
`java.time.temporal.UnsupportedTemporalTypeException`	if the field is not supported by the temporal
`java.lang.ArithmeticException`	if numeric overflow occurs

getBaseUnit

Added in API level 26

abstract fun getBaseUnit(): TemporalUnit!

Gets the unit that the field is measured in.

The unit of the field is the period that varies within the range. For example, in the field 'MonthOfYear', the unit is 'Months'. See also getRangeUnit().

Return
`TemporalUnit!`	the unit defining the base unit of the field, not null

getDisplayName

Added in API level 26

open fun getDisplayName(locale: Locale!): String!

Gets the display name for the field in the requested locale.

If there is no display name for the locale then a suitable default must be returned.

The default implementation must check the locale is not null and return toString().

Parameters
`locale`	Locale!: the locale to use, not null

Return
`String!`	the display name for the locale or a suitable default, not null

getFrom

Added in API level 26

abstract fun getFrom(temporal: TemporalAccessor!): Long

Gets the value of this field from the specified temporal object.

This queries the temporal object for the value of this field.

There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use TemporalAccessor#getLong(TemporalField) (or TemporalAccessor#get(TemporalField)):

// these two lines are equivalent, but the second approach is recommended
    temporal = thisField.getFrom(temporal);
    temporal = temporal.getLong(thisField);

It is recommended to use the second approach, getLong(TemporalField), as it is a lot clearer to read in code.

Implementations should perform any queries or calculations using the fields available in ChronoField. If the field is not supported an UnsupportedTemporalTypeException must be thrown.

Parameters
`temporal`	TemporalAccessor!: the temporal object to query, not null

Return
`Long`	the value of this field, not null

Exceptions
`java.time.DateTimeException`	if a value for the field cannot be obtained
`java.time.temporal.UnsupportedTemporalTypeException`	if the field is not supported by the temporal
`java.lang.ArithmeticException`	if numeric overflow occurs

getRangeUnit

Added in API level 26

abstract fun getRangeUnit(): TemporalUnit!

Gets the range that the field is bound by.

The range of the field is the period that the field varies within. For example, in the field 'MonthOfYear', the range is 'Years'. See also getBaseUnit().

The range is never null. For example, the 'Year' field is shorthand for 'YearOfForever'. It therefore has a unit of 'Years' and a range of 'Forever'.

Return
`TemporalUnit!`	the unit defining the range of the field, not null

isDateBased

Added in API level 26

abstract fun isDateBased(): Boolean

Checks if this field represents a component of a date.

A field is date-based if it can be derived from EPOCH_DAY. Note that it is valid for both isDateBased() and isTimeBased() to return false, such as when representing a field like minute-of-week.

Return
`Boolean`	true if this field is a component of a date

isSupportedBy

Added in API level 26

abstract fun isSupportedBy(temporal: TemporalAccessor!): Boolean

Checks if this field is supported by the temporal object.

This determines whether the temporal accessor supports this field. If this returns false, then the temporal cannot be queried for this field.

There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use TemporalAccessor#isSupported(TemporalField):

// these two lines are equivalent, but the second approach is recommended
    temporal = thisField.isSupportedBy(temporal);
    temporal = temporal.isSupported(thisField);

It is recommended to use the second approach, isSupported(TemporalField), as it is a lot clearer to read in code.

Implementations should determine whether they are supported using the fields available in ChronoField.

Parameters
`temporal`	TemporalAccessor!: the temporal object to query, not null

Return
`Boolean`	true if the date-time can be queried for this field, false if not

isTimeBased

Added in API level 26

abstract fun isTimeBased(): Boolean

Checks if this field represents a component of a time.

A field is time-based if it can be derived from NANO_OF_DAY. Note that it is valid for both isDateBased() and isTimeBased() to return false, such as when representing a field like minute-of-week.

Return
`Boolean`	true if this field is a component of a time

range

Added in API level 26

abstract fun range(): ValueRange!

Gets the range of valid values for the field.

All fields can be expressed as a long integer. This method returns an object that describes the valid range for that value. This method is generally only applicable to the ISO-8601 calendar system.

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.

Return
`ValueRange!`	the range of valid values for the field, not null

rangeRefinedBy

Added in API level 26

abstract fun rangeRefinedBy(temporal: TemporalAccessor!): ValueRange!

Get the range of valid values for this field using the temporal object to refine the result.

This uses the temporal object to find the range of valid values for the field. This is similar to range(), however this method refines the result using the temporal. For example, if the field is DAY_OF_MONTH the range method is not accurate as there are four possible month lengths, 28, 29, 30 and 31 days. Using this method with a date allows the range to be accurate, returning just one of those four options.

There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use TemporalAccessor#range(TemporalField):

// these two lines are equivalent, but the second approach is recommended
    temporal = thisField.rangeRefinedBy(temporal);
    temporal = temporal.range(thisField);

It is recommended to use the second approach, range(TemporalField), as it is a lot clearer to read in code.

Implementations should perform any queries or calculations using the fields available in ChronoField. If the field is not supported an UnsupportedTemporalTypeException must be thrown.

Parameters
`temporal`	TemporalAccessor!: the temporal object used to refine the result, not null

Return
`ValueRange!`	the range of valid values for this field, not null

Exceptions
`java.time.DateTimeException`	if the range for the field cannot be obtained
`java.time.temporal.UnsupportedTemporalTypeException`	if the field is not supported by the temporal

resolve

Added in API level 26

open fun resolve(
    fieldValues: MutableMap<TemporalField!, Long!>!, 
    partialTemporal: TemporalAccessor!, 
    resolverStyle: ResolverStyle!
): TemporalAccessor!

Resolves this field to provide a simpler alternative or a date.

This method is invoked during the resolve phase of parsing. It is designed to allow application defined fields to be simplified into more standard fields, such as those on ChronoField, or into a date.

Applications should not normally invoke this method directly.

Parameters
`fieldValues`	MutableMap<TemporalField!, Long!>!: the map of fields to values, which can be updated, not null
`partialTemporal`	TemporalAccessor!: the partially complete temporal to query for zone and chronology; querying for other things is undefined and not recommended, not null
`resolverStyle`	ResolverStyle!: the requested type of resolve, not null

Return
`TemporalAccessor!`	the resolved temporal object; null if resolving only changed the map, or no resolve occurred

Exceptions
`java.lang.ArithmeticException`	if numeric overflow occurs
`java.time.DateTimeException`	if resolving results in an error. This must not be thrown by querying a field on the temporal without first checking if it is supported