Gets the zone offset, such as '+01:00'.
Gets the zone offset, such as '+01:00'.
This is the offset of the local date-time from UTC/Greenwich.
the zone offset, not null
Gets the zone ID, such as 'Europe/Paris'.
Gets the zone ID, such as 'Europe/Paris'.
This returns the stored time-zone id used to determine the time-zone rules.
the zone ID, not null
Checks if the specified unit is supported.
Checks if the specified unit is supported.
This checks if the date-time can be queried for the specified unit.
If false, then calling the plus
and minus
methods will throw an exception.
Implementations must check and handle all fields defined in ChronoUnit
.
If the field is supported, then true is returned, otherwise false
If the field is not a ChronoUnit
, then the result of this method
is obtained by invoking TemporalUnit.isSupportedBy(Temporal)
passing this
as the argument.
Implementations must not alter this object.
the unit to check, null returns false
true if this date-time can be queried for the unit, false if not
Checks if the specified field is supported.
Checks if the specified field is supported.
This checks if the date-time can be queried for the specified field.
If false, then calling the range
and get
methods will throw an exception.
Implementations must check and handle all fields defined in ChronoField
.
If the field is supported, then true is returned, otherwise false
If the field is not a ChronoField
, then the result of this method
is obtained by invoking TemporalField.isSupportedBy(TemporalAccessor)
passing this
as the argument.
Implementations must not alter this object.
the field to check, null returns false
true if this date-time can be queried for the field, false if not
Returns an object of the same type as this object with the specified period added.
Returns an object of the same type as this object with the specified period added.
This method returns a new object based on this one with the specified period added.
For example, on a LocalDate
, this could be used to add a number of years, months or days.
The returned object will have the same observable type as this 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 adding one month would be unclear. In cases like this, the field 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.
If the implementation represents a date-time that has boundaries, such as LocalTime
,
then the permitted units must include the boundary unit, but no multiples of the boundary unit.
For example, LocalTime
must accept DAYS
but not WEEKS
or MONTHS
.
Implementations must check and handle all units defined in ChronoUnit
.
If the unit is supported, then the addition must be performed.
If unsupported, then a DateTimeException
must be thrown.
If the unit is not a ChronoUnit
, then the result of this method
is obtained by invoking TemporalUnit.addTo(Temporal, long)
passing this
as the first argument.
Implementations must not alter either this object or the specified temporal object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the amount of the specified unit to add, may be negative
the unit of the period to add, not null
an object of the same type with the specified period added, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the unit cannot be added
Gets the local date-time part of this date-time.
Gets the local date-time part of this date-time.
This returns a local date with the same year, month and day as this date-time.
the local date-time part of this date-time, not null
Calculates the period between this temporal and another temporal in terms of the specified unit.
Calculates the period between this temporal and another temporal in terms of the specified unit.
This calculates the period between two temporals in terms of a single unit.
The start and end points are this
and the specified temporal.
The result will be negative if the end is before the start.
For example, the period in hours between two temporal objects can be
calculated using startTime.until(endTime, HOURS)
.
The calculation returns a whole number, representing the number of complete units between the two temporals. For example, the period in hours between the times 11:30 and 13:29 will only be one hour as it is one minute short of two hours.
There are two equivalent ways of using this method.
The first is to invoke this method directly.
The second is to use Temporal)
:
// these two lines are equivalent between = thisUnit.between(start, end); between = start.until(end, thisUnit);The choice should be made based on which makes the code more readable.
For example, this method allows the number of days between two dates to be calculated:
val daysBetween: Long = DAYS.between(start, end); // or alternatively val daysBetween: Long = start.until(end, DAYS);
Implementations must begin by checking to ensure that the input temporal
object is of the same observable type as the implementation.
They must then perform the calculation for all instances of ChronoUnit
.
A DateTimeException
must be thrown for ChronoUnit
instances that are unsupported.
If the unit is not a ChronoUnit
, then the result of this method
is obtained by invoking TemporalUnit.between(Temporal, Temporal)
passing this
as the first argument and the input temporal as
the second argument.
In summary, implementations must behave in a manner equivalent to this code:
// check input temporal is the same type as this class if (unit instanceof ChronoUnit) { // if unit is supported, then calculate and return result // else throw DateTimeException for unsupported units } return unit.between(this, endTemporal);
The target object must not be altered by this method.
the end temporal, of the same type as this object, not null
the unit to measure the period in, not null
the amount of the period between this and the end
ArithmeticException
if numeric overflow occurs
DateTimeException
if the period cannot be calculated
Returns an object of the same type as this object with the specified field altered.
Returns an object of the same type as this object with the specified field altered.
This returns a new object based on this one with the value for the specified field changed.
For example, on a LocalDate
, this could be used to set the year, month or day-of-month.
The returned object will have the same observable type as this 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 field 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.
Implementations must check and handle all fields defined in ChronoField
.
If the field is supported, then the adjustment must be performed.
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.adjustInto(Temporal, long)
passing this
as the first argument.
Implementations must not alter either this object or the specified temporal object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the field to set in the result, not null
the new value of the field in the result
an object of the same type with the specified field set, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the field cannot be set
Returns a copy of this date-time changing the zone offset to the earlier of the two valid offsets at a local time-line overlap.
Returns a copy of this date-time changing the zone offset to the earlier of the two valid offsets at a local time-line overlap.
This method only has any effect when the local time-line overlaps, such as at an autumn daylight savings cutover. In this scenario, there are two valid offsets for the local date-time. Calling this method will return a zoned date-time with the earlier of the two selected.
If this method is called when it is not an overlap, this
is returned.
This instance is immutable and unaffected by this method call.
a { @code ZoneChronoDateTime} based on this date-time with the earlier offset, not null
DateTimeException
if no rules are valid for this date-time
Returns a copy of this date-time changing the zone offset to the later of the two valid offsets at a local time-line overlap.
Returns a copy of this date-time changing the zone offset to the later of the two valid offsets at a local time-line overlap.
This method only has any effect when the local time-line overlaps, such as at an autumn daylight savings cutover. In this scenario, there are two valid offsets for the local date-time. Calling this method will return a zoned date-time with the later of the two selected.
If this method is called when it is not an overlap, this
is returned.
This instance is immutable and unaffected by this method call.
a { @code ChronoZonedDateTime} based on this date-time with the later offset, not null
DateTimeException
if no rules are valid for this date-time
Returns a copy of this date-time with a different time-zone, retaining the instant.
Returns a copy of this date-time with a different time-zone, retaining the instant.
This method changes the time-zone and retains the instant. This normally results in a change to the local date-time.
This method is based on retaining the same instant, thus gaps and overlaps in the local time-line have no effect on the result.
To change the offset while keeping the local time,
use #withZoneSameLocal(ZoneId)
.
the time-zone to change to, not null
a { @code ChronoZonedDateTime} based on this date-time with the requested zone, not null
DateTimeException
if the result exceeds the supported date range
Returns a copy of this ZonedDateTime with a different time-zone, retaining the local date-time if possible.
Returns a copy of this ZonedDateTime with a different time-zone, retaining the local date-time if possible.
This method changes the time-zone and retains the local date-time. The local date-time is only changed if it is invalid for the new zone.
To change the zone and adjust the local date-time,
use #withZoneSameInstant(ZoneId)
.
This instance is immutable and unaffected by this method call.
the time-zone to change to, not null
a { @code ChronoZonedDateTime} based on this date-time with the requested zone, not null
Compares this date-time to another date-time, including the chronology.
Compares this date-time to another date-time, including the chronology.
The comparison is based first on the instant, then on the local date-time,
then on the zone ID, then on the chronology.
It is "consistent with equals", as defined by Comparable
.
If all the date-time objects being compared are in the same chronology, then the additional chronology stage is not required.
the other date-time to compare to, not null
the comparator value, negative if less, positive if greater
Checks if this date-time is equal to another date-time.
Checks if this date-time is equal to another date-time.
The comparison is based on the offset date-time and the zone.
To compare for the same instant on the time-line, use #compareTo
.
Only objects of type ChronoZoneDateTime
are compared, other types return false.
the object to check, null returns false
true if this is equal to the other date-time
Outputs this date-time as a String
using the formatter.
Outputs this date-time as a String
using the formatter.
the formatter to use, not null
the formatted date-time string, not null
DateTimeException
if an error occurs during printing
Gets the value of the specified field as an int
.
Gets the value of the specified field as an int
.
This queries the date-time for the value for the specified field. The returned value will always be within the valid range of values for the field. If the date-time cannot return the value, because the field is unsupported or for some other reason, an exception will be thrown.
Implementations must check and handle all fields defined in ChronoField
.
If the field is supported and has an int
range, then the value 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.getFrom(TemporalAccessor)
passing this
as the argument.
Implementations must not alter either this object.
the field to get, not null
the value for the field, within the valid range of values
ArithmeticException
if numeric overflow occurs
DateTimeException
if the value is outside the range of valid values for the field
Gets the chronology of this date-time.
Gets the chronology of this date-time.
The Chronology
represents the calendar system in use.
The era and other fields in ChronoField
are defined by the chronology.
the chronology, not null
Gets the value of the specified field as a long
.
Gets the value of the specified field as a long
.
This queries the date-time for the value for the specified field. The returned value may be outside the valid range of values for the field. If the date-time cannot return the value, because the field is unsupported or for some other reason, an exception will be thrown.
Implementations must check and handle all fields defined in ChronoField
.
If the field is supported, then the value 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.getFrom(TemporalAccessor)
passing this
as the argument.
Implementations must not alter either this object.
the field to get, not null
the value for the field
ArithmeticException
if numeric overflow occurs
DateTimeException
if a value for the field cannot be obtained
A hash code for this date-time.
A hash code for this date-time.
a suitable hash code
Checks if the instant of this date-time is after that of the specified date-time.
Checks if the instant of this date-time is after that of the specified date-time.
This method differs from the comparison in #compareTo
in that it
only compares the instant of the date-time. This is equivalent to using
dateTime1.toInstant().isAfter(dateTime2.toInstant());
.
the other date-time to compare to, not null
true if this is after the specified date-time
Checks if the instant of this date-time is before that of the specified date-time.
Checks if the instant of this date-time is before that of the specified date-time.
This method differs from the comparison in #compareTo
in that it
only compares the instant of the date-time. This is equivalent to using
dateTime1.toInstant().isBefore(dateTime2.toInstant());
.
the other date-time to compare to, not null
true if this point is before the specified date-time
Checks if the instant of this date-time is equal to that of the specified date-time.
Checks if the instant of this date-time is equal to that of the specified date-time.
This method differs from the comparison in #compareTo
and #equals
in that it only compares the instant of the date-time. This is equivalent to using
dateTime1.toInstant().equals(dateTime2.toInstant());
.
the other date-time to compare to, not null
true if the instant equals the instant of the specified date-time
Returns an object of the same type as this object with the specified period subtracted.
Returns an object of the same type as this object with the specified period subtracted.
This method returns a new object based on this one with the specified period subtracted.
For example, on a LocalDate
, this could be used to subtract a number of years, months or days.
The returned object will have the same observable type as this object.
In some cases, changing a field is not fully defined. For example, if the target object is a date representing the 31st March, then subtracting one month would be unclear. In cases like this, the field 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.
If the implementation represents a date-time that has boundaries, such as LocalTime
,
then the permitted units must include the boundary unit, but no multiples of the boundary unit.
For example, LocalTime
must accept DAYS
but not WEEKS
or MONTHS
.
Implementations must behave in a manor equivalent to the default method behavior.
Implementations must not alter either this object or the specified temporal object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the amount of the specified unit to subtract, may be negative
the unit of the period to subtract, not null
an object of the same type with the specified period subtracted, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the unit cannot be subtracted
Returns an object of the same type as this object with an amount subtracted.
Returns an object of the same type as this object with an amount subtracted.
This adjusts this temporal, subtracting according to the rules of the specified amount.
The amount is typically a Period
but may be any other type implementing
the TemporalAmount
interface, such as Duration
.
Some example code indicating how and why this method is used:
date = date.minus(period); // subtract a Period instance date = date.minus(duration); // subtract a Duration instance date = date.minus(workingDays(6)); // example user-written workingDays method
Note that calling plus
followed by minus
is not guaranteed to
return the same date-time.
Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the amount to subtract, not null
an object of the same type with the specified adjustment made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the subtraction cannot be made
Returns an object of the same type as this object with an amount added.
Returns an object of the same type as this object with an amount added.
This adjusts this temporal, adding according to the rules of the specified amount.
The amount is typically a Period
but may be any other type implementing
the TemporalAmount
interface, such as Duration
.
Some example code indicating how and why this method is used:
date = date.plus(period); // add a Period instance date = date.plus(duration); // add a Duration instance date = date.plus(workingDays(6)); // example user-written workingDays method
Note that calling plus
followed by minus
is not guaranteed to
return the same date-time.
Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the amount to add, not null
an object of the same type with the specified adjustment made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the addition cannot be made
Queries this date-time.
Queries this date-time.
This queries this date-time using the specified query strategy object.
Queries are a key tool for extracting information from date-times. They exists to externalize the process of querying, permitting different approaches, as per the strategy design pattern. Examples might be a query that checks if the date is the day before February 29th in a leap year, or calculates the number of days to your next birthday.
The most common query implementations are method references, such as
LocalDate::from
and ZoneId::from
.
Further implementations are on TemporalQueries
.
Queries may also be defined by applications.
Implementations of this method must behave as follows:
public <R> R query(TemporalQuery<R> type) { // only include an if statement if the implementation can return it if (query == TemporalQueries.zoneId()) return // the ZoneId if (query == TemporalQueries.chronology()) return // the Chrono if (query == TemporalQueries.precision()) return // the precision // call default method return super.query(query); }
the type of the result
the query to invoke, not null
the query result, null may be returned (defined by the query)
ArithmeticException
if numeric overflow occurs
DateTimeException
if unable to query
Gets the range of valid values for the specified field.
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.
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.
the field to query the range for, not null
the range of valid values for the field, not null
DateTimeException
if the range for the field cannot be obtained
Converts this date-time to the number of seconds from the epoch of 1970-01-01T00:00:00Z.
Converts this date-time to the number of seconds from the epoch of 1970-01-01T00:00:00Z.
This uses the local date-time and offset to calculate the epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z. Instants on the time-line after the epoch are positive, earlier are negative.
the number of seconds from the epoch of 1970-01-01T00:00:00Z
Converts this date-time to an Instant
.
Converts this date-time to an Instant
.
This returns an Instant
representing the same point on the
time-line as this date-time. The calculation combines the
local date-time and
offset.
an { @code Instant} representing the same instant, not null
Gets the local date part of this date-time.
Gets the local date part of this date-time.
This returns a local date with the same year, month and day as this date-time.
the date part of this date-time, not null
Gets the local time part of this date-time.
Gets the local time part of this date-time.
This returns a local time with the same hour, minute, second and nanosecond as this date-time.
the time part of this date-time, not null
Outputs this date-time as a String
.
Outputs this date-time as a String
.
The output will include the full zoned date-time and the chronology ID.
a string representation of this date-time, not null
Returns an adjusted object of the same type as this object with the adjustment made.
Returns an adjusted object of the same type as this object with the adjustment made.
This adjusts this date-time according to the rules of the specified adjuster.
A simple adjuster might simply set the one of the fields, such as the year field.
A more complex adjuster might set the date to the last day of the month.
A selection of common adjustments is provided in TemporalAdjusters
.
These include finding the "last day of the month" and "next Wednesday".
The adjuster is responsible for handling special cases, such as the varying
lengths of month and leap years.
Some example code indicating how and why this method is used:
date = date.with(Month.JULY); // most key classes implement TemporalAdjuster date = date.with(lastDayOfMonth()); // static import from TemporalAdjusters date = date.with(next(WEDNESDAY)); // static import from TemporalAdjusters and DayOfWeek
Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
the adjuster to use, not null
an object of the same type with the specified adjustment made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if unable to make the adjustment
A date-time with a time-zone in an arbitrary chronology, intended for advanced globalization use cases.
Most applications should declare method signatures, fields and variables as `[[ZonedDateTime]]`, not this interface.
A
ChronoZonedDateTime
is the abstract representation of an offset date-time where theChronology chronology
, or calendar system, is pluggable. The date-time is defined in terms of fields expressed byTemporalField
, where most common implementations are defined inChronoField
. The chronology defines how the calendar system operates and the meaning of the standard fields.When to use this interface
The design of the API encourages the use of
ZonedDateTime
rather than this interface, even in the case where the application needs to deal with multiple calendar systems. The rationale for this is explored in detail inChronoLocalDate
.Ensure that the discussion in
ChronoLocalDate
has been read and understood before using this interface.Specification for implementors
This interface must be implemented with care to ensure other classes operate correctly. All implementations that can be instantiated must be final, immutable and thread-safe. Subclasses should be Serializable wherever possible.
the date type