Known Indirect Subclasses |
Framework-level interface defining an amount of time, such as "6 hours", "8 days" or "2 years and 3 months".
This is the base interface type for amounts of time. An amount is distinct from a date or time-of-day in that it is not tied to any specific point on the time-line.
The amount can be thought of as a Map
of TemporalUnit
to
long
, exposed via getUnits()
and get(TemporalUnit)
.
A simple case might have a single unit-value pair, such as "6 hours".
A more complex case may have multiple unit-value pairs, such as
"7 years, 3 months and 5 days".
There are two common implementations.
Period
is a date-based implementation, storing years, months and days.
Duration
is a time-based implementation, storing seconds and nanoseconds,
but providing some access using other duration based units such as minutes,
hours and fixed 24-hour days.
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 Period
and Duration
.
Public Method Summary
abstract Temporal | |
abstract long | |
abstract List<TemporalUnit> |
getUnits()
Returns the list of units uniquely defining the value of this TemporalAmount.
|
abstract Temporal |
Public Methods
public abstract Temporal addTo (Temporal temporal)
Adds to the specified temporal object.
Adds the amount to the specified temporal object using the logic encapsulated in the implementing class.
There are two equivalent ways of using this method.
The first is to invoke this method directly.
The second is to use Temporal.plus(TemporalAmount)
:
// These two lines are equivalent, but the second approach is recommended dateTime = amount.addTo(dateTime); dateTime = dateTime.plus(adder);It is recommended to use the second approach,
plus(TemporalAmount)
,
as it is a lot clearer to read in code.Parameters
temporal | the temporal object to add the amount to, not null |
---|
Returns
- an object of the same observable type with the addition made, not null
Throws
DateTimeException | if unable to add |
---|---|
ArithmeticException | if numeric overflow occurs |
public abstract long get (TemporalUnit unit)
Returns the value of the requested unit.
The units returned from getUnits()
uniquely define the
value of the TemporalAmount
. A value must be returned
for each unit listed in getUnits
.
Parameters
unit | the TemporalUnit for which to return the value |
---|
Returns
- the long value of the unit
Throws
DateTimeException | if a value for the unit cannot be obtained |
---|---|
UnsupportedTemporalTypeException | if the unit is not supported
|
public abstract List<TemporalUnit> getUnits ()
Returns the list of units uniquely defining the value of this TemporalAmount.
The list of TemporalUnits
is defined by the implementation class.
The list is a snapshot of the units at the time getUnits
is called and is not mutable.
The units are ordered from longest duration to the shortest duration
of the unit.
Returns
- the List of
TemporalUnits
; not null
public abstract Temporal subtractFrom (Temporal temporal)
Subtracts this object from the specified temporal object.
Subtracts the amount from the specified temporal object using the logic encapsulated in the implementing class.
There are two equivalent ways of using this method.
The first is to invoke this method directly.
The second is to use Temporal.minus(TemporalAmount)
:
// these two lines are equivalent, but the second approach is recommended dateTime = amount.subtractFrom(dateTime); dateTime = dateTime.minus(amount);It is recommended to use the second approach,
minus(TemporalAmount)
,
as it is a lot clearer to read in code.Parameters
temporal | the temporal object to subtract the amount from, not null |
---|
Returns
- an object of the same observable type with the subtraction made, not null
Throws
DateTimeException | if unable to subtract |
---|---|
ArithmeticException | if numeric overflow occurs |