This is the base interface type for date, time and offset objects that
are complete enough to be manipulated using plus and minus.
It is implemented by those classes that can provide and manipulate information
as fields or queries.
See TemporalAccessor for the read-only version of this interface.
Most date and time information can be represented as a number.
These are modeled using TemporalField with the number held using
a long to handle large values. Year, month and day-of-month are
simple examples of fields, but they also include instant and offsets.
See ChronoField for the standard set of fields.
Two pieces of date/time information cannot be represented by numbers,
the chronology and the
time-zone.
These can be accessed via queries using
the static methods defined on TemporalQuery.
This interface is a framework-level interface that should not be widely
used in application code. Instead, applications should create and pass
around instances of concrete types, such as LocalDate.
There are many reasons for this, part of which is that implementations
of this interface may be in calendar systems other than ISO.
See java. for a fuller discussion of the issues.
A class should implement this interface if it meets three criteria:
TemporalAccessor
Four examples make this clear:
LocalDate implements this interface as it represents a set of fields
that are contiguous from days to forever and require no external information to determine
the validity of each date. It is therefore able to implement plus/minus correctly.
LocalTime implements this interface as it represents a set of fields
that are contiguous from nanos to within days and require no external information to determine
validity. It is able to implement plus/minus correctly, by wrapping around the day.
MonthDay, the combination of month-of-year and day-of-month, does not implement
this interface. While the combination is contiguous, from days to months within years,
the combination does not have sufficient information to define the valid range of values
for day-of-month. As such, it is unable to implement plus/minus correctly.
Implementation Specification
This interface places no restrictions on the mutability of implementations,
however immutability is strongly recommended.
All implementations must be Comparable.
| Modifier and Type | Method and Description |
|---|---|
| public boolean | Returns: true if the unit can be added/subtracted, false if notthe unit to check, null returns false unit)Checks if the specified unit is supported. |
| public default Temporal | Returns: an object of the same type with the specified adjustment made, not nullthe amount to subtract, not null amount)Returns an object of the same type as this object with an amount subtracted. |
| public default Temporal | Returns: an object of the same type with the specified period subtracted, not nullthe amount of the specified unit to subtract, may be negative amountToSubtract, TemporalUnit the unit of the amount to subtract, not null unit)Returns an object of the same type as this object with the specified period subtracted. |
| public default Temporal | Returns: an object of the same type with the specified adjustment made, not nullthe amount to add, not null amount)Returns an object of the same type as this object with an amount added. |
| public Temporal | Returns: an object of the same type with the specified period added, not nullthe amount of the specified unit to add, may be negative amountToAdd, TemporalUnit the unit of the amount to add, not null unit)Returns an object of the same type as this object with the specified period added. |
| public long | Returns: the amount of time between this temporal object and the specified one in terms of the unit; positive if the specified object is later than this one, negative if it is earlier than this onethe end temporal, exclusive, converted to be of the
same type as this object, not null endExclusive, TemporalUnit the unit to measure the amount in, not null unit)Calculates the amount of time until another temporal in terms of the specified unit. |
| public default Temporal | Returns: an object of the same type with the specified adjustment made, not nullthe adjuster to use, not null adjuster)Returns an adjusted object of the same type as this object with the adjustment made. |
| public Temporal | Returns: an object of the same type with the specified field set, not nullthe field to set in the result, not null field, long the new value of the field in the result newValue)Returns an object of the same type as this object with the specified field altered. |
| isSupported | back to summary |
|---|---|
| public boolean isSupported(TemporalUnit unit) Checks if the specified unit is supported.
This checks if the specified unit can be added to, or subtracted from, this date-time.
If false, then calling the Implementation Specification Implementations must check and handle all units defined in
If the field is not a Implementations must ensure that no observable state is altered when this read-only method is invoked.
| |
| minus | back to summary |
|---|---|
| public default Temporal minus(TemporalAmount amount) 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 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 Implementation Specification 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 default implementation must behave equivalent to this code: return amount.subtractFrom(this);
| |
| minus | back to summary |
|---|---|
| public default Temporal minus(long amountToSubtract, TemporalUnit unit) 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 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. Implementation Specification Implementations must behave in a manor equivalent to the default method behavior. Implementations must not alter this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations. The default implementation must behave equivalent to this code:
return (amountToSubtract == Long.MIN_VALUE ?
plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
| |
| plus | back to summary |
|---|---|
| public default Temporal plus(TemporalAmount amount) 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 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 Implementation Specification 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 default implementation must behave equivalent to this code: return amount.addTo(this);
| |
| plus | back to summary |
|---|---|
| public Temporal plus(long amountToAdd, TemporalUnit unit) 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 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. Implementation Specification Implementations must check and handle all units defined in
If the unit is not a Implementations must not alter this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
| |
| until | back to summary |
|---|---|
| public long until(Temporal endExclusive, TemporalUnit unit) Calculates the amount of time until another temporal in terms of the specified unit.
This calculates the amount of time between two temporal objects
in terms of a single The calculation returns a whole number, representing the number of complete units between the two temporals. For example, the amount 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 // these two lines are equivalent amount = start.until(end, unit); amount = unit.between(start, end);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: long daysBetween = start.until(end, DAYS); // or alternatively long daysBetween = DAYS.between(start, end); Implementation Specification 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
If the unit is not a In summary, implementations must behave in a manner equivalent to this pseudo-code:
// convert the end temporal to the same type as this class
if (unit instanceof ChronoUnit) {
// if unit is supported, then calculate and return result
// else throw UnsupportedTemporalTypeException for unsupported units
}
return unit.between(this, convertedEndTemporal);
Note that the unit's Implementations must ensure that no observable state is altered when this read-only method is invoked.
| |
| with | back to summary |
|---|---|
| public default Temporal with(TemporalAdjuster adjuster) 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
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 Adjusters date = date.with(next(WEDNESDAY)); // static import from Adjusters and DayOfWeek Implementation Specification 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 default implementation must behave equivalent to this code: return adjuster.adjustInto(this);
| |
| with | back to summary |
|---|---|
| public Temporal with(TemporalField field, long newValue) 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 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. Implementation Specification Implementations must check and handle all fields defined in
If the field is not a Implementations must not alter this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
| |