TemporalUnit (ThreeTen Date and Time API)

All Known Implementing Classes:

ChronoUnit
```
public interface TemporalUnit
```
A unit of date-time, such as Days or Hours.
Measurement of time is built on units, such as years, months, days, hours, minutes and seconds. Implementations of this interface represent those units.
An instance of this interface represents the unit itself, rather than an amount of the unit. See Period for a class that represents an amount in terms of the common units.
The most commonly used units are defined in ChronoUnit. Further units are supplied in ISOFields. Units can also be written by application code by implementing this interface.
The unit works using double dispatch. Client code calls methods on a date-time like LocalDateTime which check if the unit is a ChronoUnit. If it is, then the date-time must handle it. Otherwise, the method call is re-dispatched to the matching method in 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. It is recommended to use an enum where possible.

Since:

1.8

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`<R extends Temporal> SimplePeriod`	`between(R dateTime1, R dateTime2)` Calculates the period in terms of this unit between two temporal objects of the same type.
`<R extends Temporal> R`	`doPlus(R dateTime, long periodToAdd)` Returns a copy of the specified temporal object with the specified period added.
`Duration`	`getDuration()` Gets the duration of this unit, which may be an estimate.
`java.lang.String`	`getName()` Gets a descriptive name for the unit.
`boolean`	`isDurationEstimated()` Checks if the duration of the unit is an estimate.
`default boolean`	`isSupported(Temporal temporal)` Checks if this unit is supported by the specified temporal object.
`java.lang.String`	`toString()` Outputs this unit as a `String` using the name.

- Method Detail
  - getName
```
java.lang.String getName()
```
    Gets a descriptive name for the unit.
    This should be in the plural and upper-first camel case, such as 'Days' or 'Minutes'.
    
    Returns:
    the name, not null
  - getDuration
```
Duration getDuration()
```
    Gets the duration of this unit, which may be an estimate.
    All units return a duration measured in standard nanoseconds from this method. For example, an hour has a duration of 60 * 60 * 1,000,000,000ns.
    Some units may return an accurate duration while others return an estimate. For example, days have an estimated duration due to the possibility of daylight saving time changes. To determine if the duration is an estimate, use isDurationEstimated().
    
    Returns:
    the duration of this unit, which may be an estimate, not null
  - isDurationEstimated
```
boolean isDurationEstimated()
```
    Checks if the duration of the unit is an estimate.
    All units have a duration, however the duration is not always accurate. For example, days have an estimated duration due to the possibility of daylight saving time changes. This method returns true if the duration is an estimate and false if it is accurate. Note that accurate/estimated ignores leap seconds.
    
    Returns:
    true if the duration is estimated, false if accurate
  - isSupported
```
default boolean isSupported(Temporal temporal)
```
    Checks if this unit is supported by the specified temporal object.
    This checks that the implementing date-time can add/subtract this unit. This can be used to avoid throwing an exception.
    This default implementation derives the value using Temporal.plus(long, TemporalUnit).
    
    Parameters:
    temporal - the temporal object to check, not null
    
    Returns:
    true if the unit is supported
  - doPlus
```
<R extends Temporal> R doPlus(R dateTime,
                            long periodToAdd)
```
    Returns a copy of the specified temporal object with the specified period added.
    The period added is a multiple of this unit. For example, this method could be used to add "3 days" to a date by calling this method on the instance representing "days", passing the date and the period "3". The period to be added may be negative, which is equivalent to subtraction.
    There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use Temporal.plus(long, TemporalUnit):
```
   // these two lines are equivalent, but the second approach is recommended
   temporal = thisUnit.doPlus(temporal);
   temporal = temporal.plus(thisUnit);
 
```
    It is recommended to use the second approach, plus(TemporalUnit), as it is a lot clearer to read in code.
    Implementations should perform any queries or calculations using the units available in ChronoUnit or the fields available in ChronoField. If the field is not supported a DateTimeException 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.
    Type Parameters:
    R - the type of the Temporal object
    Parameters:
    dateTime - the temporal object to adjust, not null
    periodToAdd - the period of this unit to add, positive or negative
    
    Returns:
    the adjusted temporal object, not null
    
    Throws:
    
    DateTimeException - if the period cannot be added
  - between
```
<R extends Temporal> SimplePeriod between(R dateTime1,
                                        R dateTime2)
```
    Calculates the period in terms of this unit between two temporal objects of the same type.
    The period will be positive if the second date-time is after the first, and negative if the second date-time is before the first. Call abs() on the result to ensure that the result is always positive.
    The result can be queried for the amount, the unit and used directly in addition/subtraction:
```
  date = date.minus(MONTHS.between(start, end));
 
```
    Type Parameters:
    R - the type of the Temporal object; the two date-times must be of the same type
    Parameters:
    dateTime1 - the base temporal object, not null
    dateTime2 - the other temporal object, not null
    
    Returns:
    the period between datetime1 and datetime2 in terms of this unit; positive if datetime2 is later than datetime1, not null
  - toString
```
java.lang.String toString()
```
    Outputs this unit as a String using the name.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    the name of this unit, not null

Interface TemporalUnit

Specification for implementors

Method Summary

Method Detail

getName

getDuration

isDurationEstimated

isSupported

doPlus

between

toString