Class Instant
- java.lang.Object
-
- java.time.Instant
-
- All Implemented Interfaces:
- Serializable, Comparable<Instant>, Temporal, TemporalAccessor, TemporalAdjuster
public final class Instant extends Object implements Temporal, TemporalAdjuster, Comparable<Instant>, Serializable
An instantaneous point on the time-line.This class models a single instantaneous point on the time-line. This might be used to record event time-stamps in the application.
The range of an instant requires the storage of a number larger than a
long
. To achieve this, the class stores along
representing epoch-seconds and anint
representing nanosecond-of-second, which will always be between 0 and 999,999,999. The epoch-seconds are measured from the standard Java epoch of1970-01-01T00:00:00Z
where instants after the epoch have positive values, and earlier instants have negative values. For both the epoch-second and nanosecond parts, a larger value is always later on the time-line than a smaller value.Time-scale
The length of the solar day is the standard way that humans measure time. This has traditionally been subdivided into 24 hours of 60 minutes of 60 seconds, forming a 86400 second day.
Modern timekeeping is based on atomic clocks which precisely define an SI second relative to the transitions of a Caesium atom. The length of an SI second was defined to be very close to the 86400th fraction of a day.
Unfortunately, as the Earth rotates the length of the day varies. In addition, over time the average length of the day is getting longer as the Earth slows. As a result, the length of a solar day in 2012 is slightly longer than 86400 SI seconds. The actual length of any given day and the amount by which the Earth is slowing are not predictable and can only be determined by measurement. The UT1 time-scale captures the accurate length of day, but is only available some time after the day has completed.
The UTC time-scale is a standard approach to bundle up all the additional fractions of a second from UT1 into whole seconds, known as leap-seconds. A leap-second may be added or removed depending on the Earth's rotational changes. As such, UTC permits a day to have 86399 SI seconds or 86401 SI seconds where necessary in order to keep the day aligned with the Sun.
The modern UTC time-scale was introduced in 1972, introducing the concept of whole leap-seconds. Between 1958 and 1972, the definition of UTC was complex, with minor sub-second leaps and alterations to the length of the notional second. As of 2012, discussions are underway to change the definition of UTC again, with the potential to remove leap seconds or introduce other changes.
Given the complexity of accurate timekeeping described above, this Java API defines its own time-scale, the Java Time-Scale.
The Java Time-Scale divides each calendar day into exactly 86400 subdivisions, known as seconds. These seconds may differ from the SI second. It closely matches the de facto international civil time scale, the definition of which changes from time to time.
The Java Time-Scale has slightly different definitions for different segments of the time-line, each based on the consensus international time scale that is used as the basis for civil time. Whenever the internationally-agreed time scale is modified or replaced, a new segment of the Java Time-Scale must be defined for it. Each segment must meet these requirements:
- the Java Time-Scale shall closely match the underlying international civil time scale;
- the Java Time-Scale shall exactly match the international civil time scale at noon each day;
- the Java Time-Scale shall have a precisely-defined relationship to the international civil time scale.
For the segment from 1972-11-03 (exact boundary discussed below) until further notice, the consensus international time scale is UTC (with leap seconds). In this segment, the Java Time-Scale is identical to UTC-SLS. This is identical to UTC on days that do not have a leap second. On days that do have a leap second, the leap second is spread equally over the last 1000 seconds of the day, maintaining the appearance of exactly 86400 seconds per day.
For the segment prior to 1972-11-03, extending back arbitrarily far, the consensus international time scale is defined to be UT1, applied proleptically, which is equivalent to the (mean) solar time on the prime meridian (Greenwich). In this segment, the Java Time-Scale is identical to the consensus international time scale. The exact boundary between the two segments is the instant where UT1 = UTC between 1972-11-03T00:00 and 1972-11-04T12:00.
Implementations of the Java time-scale using the JSR-310 API are not required to provide any clock that is sub-second accurate, or that progresses monotonically or smoothly. Implementations are therefore not required to actually perform the UTC-SLS slew or to otherwise be aware of leap seconds. JSR-310 does, however, require that implementations must document the approach they use when defining a clock representing the current instant. See
Clock
for details on the available clocks.The Java time-scale is used for all date-time classes. This includes
Instant
,LocalDate
,LocalTime
,OffsetDateTime
,ZonedDateTime
andDuration
.This is a value-based class; use of identity-sensitive operations (including reference equality (
==
), identity hash code, or synchronization) on instances ofInstant
may have unpredictable results and should be avoided. Theequals
method should be used for comparisons.- Implementation Requirements:
- This class is immutable and thread-safe.
- Since:
- 1.8
- See Also:
- Serialized Form
-
-
Field Summary
Fields Modifier and Type Field and Description static Instant
EPOCH
Constant for the 1970-01-01T00:00:00Z epoch instant.static Instant
MAX
The maximum supportedInstant
, '1000000000-12-31T23:59:59.999999999Z'.static Instant
MIN
The minimum supportedInstant
, '-1000000000-01-01T00:00Z'.
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method and Description Temporal
adjustInto(Temporal temporal)
Adjusts the specified temporal object to have this instant.OffsetDateTime
atOffset(ZoneOffset offset)
Combines this instant with an offset to create anOffsetDateTime
.ZonedDateTime
atZone(ZoneId zone)
Combines this instant with a time-zone to create aZonedDateTime
.int
compareTo(Instant otherInstant)
Compares this instant to the specified instant.boolean
equals(Object otherInstant)
Checks if this instant is equal to the specified instant.static Instant
from(TemporalAccessor temporal)
Obtains an instance ofInstant
from a temporal object.int
get(TemporalField field)
Gets the value of the specified field from this instant as anint
.long
getEpochSecond()
Gets the number of seconds from the Java epoch of 1970-01-01T00:00:00Z.long
getLong(TemporalField field)
Gets the value of the specified field from this instant as along
.int
getNano()
Gets the number of nanoseconds, later along the time-line, from the start of the second.int
hashCode()
Returns a hash code for this instant.boolean
isAfter(Instant otherInstant)
Checks if this instant is after the specified instant.boolean
isBefore(Instant otherInstant)
Checks if this instant is before the specified instant.boolean
isSupported(TemporalField field)
Checks if the specified field is supported.boolean
isSupported(TemporalUnit unit)
Checks if the specified unit is supported.Instant
minus(long amountToSubtract, TemporalUnit unit)
Returns a copy of this instant with the specified amount subtracted.Instant
minus(TemporalAmount amountToSubtract)
Returns a copy of this instant with the specified amount subtracted.Instant
minusMillis(long millisToSubtract)
Returns a copy of this instant with the specified duration in milliseconds subtracted.Instant
minusNanos(long nanosToSubtract)
Returns a copy of this instant with the specified duration in nanoseconds subtracted.Instant
minusSeconds(long secondsToSubtract)
Returns a copy of this instant with the specified duration in seconds subtracted.static Instant
now()
Obtains the current instant from the system clock.static Instant
now(Clock clock)
Obtains the current instant from the specified clock.static Instant
ofEpochMilli(long epochMilli)
Obtains an instance ofInstant
using milliseconds from the epoch of 1970-01-01T00:00:00Z.static Instant
ofEpochSecond(long epochSecond)
Obtains an instance ofInstant
using seconds from the epoch of 1970-01-01T00:00:00Z.static Instant
ofEpochSecond(long epochSecond, long nanoAdjustment)
Obtains an instance ofInstant
using seconds from the epoch of 1970-01-01T00:00:00Z and nanosecond fraction of second.static Instant
parse(CharSequence text)
Obtains an instance ofInstant
from a text string such as2007-12-03T10:15:30.00Z
.Instant
plus(long amountToAdd, TemporalUnit unit)
Returns a copy of this instant with the specified amount added.Instant
plus(TemporalAmount amountToAdd)
Returns a copy of this instant with the specified amount added.Instant
plusMillis(long millisToAdd)
Returns a copy of this instant with the specified duration in milliseconds added.Instant
plusNanos(long nanosToAdd)
Returns a copy of this instant with the specified duration in nanoseconds added.Instant
plusSeconds(long secondsToAdd)
Returns a copy of this instant with the specified duration in seconds added.<R> R
query(TemporalQuery<R> query)
Queries this instant using the specified query.ValueRange
range(TemporalField field)
Gets the range of valid values for the specified field.long
toEpochMilli()
Converts this instant to the number of milliseconds from the epoch of 1970-01-01T00:00:00Z.String
toString()
A string representation of this instant using ISO-8601 representation.Instant
truncatedTo(TemporalUnit unit)
Returns a copy of thisInstant
truncated to the specified unit.long
until(Temporal endExclusive, TemporalUnit unit)
Calculates the amount of time until another instant in terms of the specified unit.Instant
with(TemporalAdjuster adjuster)
Returns an adjusted copy of this instant.Instant
with(TemporalField field, long newValue)
Returns a copy of this instant with the specified field set to a new value.
-
-
-
Field Detail
EPOCH
public static final Instant EPOCH
Constant for the 1970-01-01T00:00:00Z epoch instant.
MIN
public static final Instant MIN
The minimum supportedInstant
, '-1000000000-01-01T00:00Z'. This could be used by an application as a "far past" instant.This is one year earlier than the minimum
LocalDateTime
. This provides sufficient values to handle the range ofZoneOffset
which affect the instant in addition to the local date-time. The value is also chosen such that the value of the year fits in anint
.
MAX
public static final Instant MAX
The maximum supportedInstant
, '1000000000-12-31T23:59:59.999999999Z'. This could be used by an application as a "far future" instant.This is one year later than the maximum
LocalDateTime
. This provides sufficient values to handle the range ofZoneOffset
which affect the instant in addition to the local date-time. The value is also chosen such that the value of the year fits in anint
.
-
Method Detail
now
public static Instant now()
Obtains the current instant from the system clock.This will query the
system UTC clock
to obtain the current instant.Using this method will prevent the ability to use an alternate time-source for testing because the clock is effectively hard-coded.
- Returns:
- the current instant using the system clock, not null
now
public static Instant now(Clock clock)
Obtains the current instant from the specified clock.This will query the specified clock to obtain the current time.
Using this method allows the use of an alternate clock for testing. The alternate clock may be introduced using
dependency injection
.- Parameters:
-
clock
- the clock to use, not null - Returns:
- the current instant, not null
ofEpochSecond
public static Instant ofEpochSecond(long epochSecond)
Obtains an instance ofInstant
using seconds from the epoch of 1970-01-01T00:00:00Z.The nanosecond field is set to zero.
- Parameters:
-
epochSecond
- the number of seconds from 1970-01-01T00:00:00Z - Returns:
- an instant, not null
- Throws:
-
DateTimeException
- if the instant exceeds the maximum or minimum instant
ofEpochSecond
public static Instant ofEpochSecond(long epochSecond, long nanoAdjustment)
Obtains an instance ofInstant
using seconds from the epoch of 1970-01-01T00:00:00Z and nanosecond fraction of second.This method allows an arbitrary number of nanoseconds to be passed in. The factory will alter the values of the second and nanosecond in order to ensure that the stored nanosecond is in the range 0 to 999,999,999. For example, the following will result in the exactly the same instant:
Instant.ofEpochSecond(3, 1); Instant.ofEpochSecond(4, -999_999_999); Instant.ofEpochSecond(2, 1000_000_001);
- Parameters:
-
epochSecond
- the number of seconds from 1970-01-01T00:00:00Z -
nanoAdjustment
- the nanosecond adjustment to the number of seconds, positive or negative - Returns:
- an instant, not null
- Throws:
-
DateTimeException
- if the instant exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
ofEpochMilli
public static Instant ofEpochMilli(long epochMilli)
Obtains an instance ofInstant
using milliseconds from the epoch of 1970-01-01T00:00:00Z.The seconds and nanoseconds are extracted from the specified milliseconds.
- Parameters:
-
epochMilli
- the number of milliseconds from 1970-01-01T00:00:00Z - Returns:
- an instant, not null
- Throws:
-
DateTimeException
- if the instant exceeds the maximum or minimum instant
from
public static Instant from(TemporalAccessor temporal)
Obtains an instance ofInstant
from a temporal object.This obtains an instant based on the specified temporal. A
TemporalAccessor
represents an arbitrary set of date and time information, which this factory converts to an instance ofInstant
.The conversion extracts the
INSTANT_SECONDS
andNANO_OF_SECOND
fields.This method matches the signature of the functional interface
TemporalQuery
allowing it to be used as a query via method reference,Instant::from
.- Parameters:
-
temporal
- the temporal object to convert, not null - Returns:
- the instant, not null
- Throws:
-
DateTimeException
- if unable to convert to anInstant
parse
public static Instant parse(CharSequence text)
Obtains an instance ofInstant
from a text string such as2007-12-03T10:15:30.00Z
.The string must represent a valid instant in UTC and is parsed using
DateTimeFormatter.ISO_INSTANT
.- Parameters:
-
text
- the text to parse, not null - Returns:
- the parsed instant, not null
- Throws:
-
DateTimeParseException
- if the text cannot be parsed
isSupported
public boolean isSupported(TemporalField field)
Checks if the specified field is supported.This checks if this instant can be queried for the specified field. If false, then calling the
range
,get
andwith(TemporalField, long)
methods will throw an exception.If the field is a
ChronoField
then the query is implemented here. The supported fields are:NANO_OF_SECOND
MICRO_OF_SECOND
MILLI_OF_SECOND
INSTANT_SECONDS
ChronoField
instances will return false.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.isSupportedBy(TemporalAccessor)
passingthis
as the argument. Whether the field is supported is determined by the field.- Specified by:
-
isSupported
in interfaceTemporalAccessor
- Parameters:
-
field
- the field to check, null returns false - Returns:
- true if the field is supported on this instant, false if not
isSupported
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
plus(long, TemporalUnit)
andminus
methods will throw an exception.If the unit is a
ChronoUnit
then the query is implemented here. The supported units are:NANOS
MICROS
MILLIS
SECONDS
MINUTES
HOURS
HALF_DAYS
DAYS
ChronoUnit
instances will return false.If the unit is not a
ChronoUnit
, then the result of this method is obtained by invokingTemporalUnit.isSupportedBy(Temporal)
passingthis
as the argument. Whether the unit is supported is determined by the unit.- Specified by:
-
isSupported
in interfaceTemporal
- Parameters:
-
unit
- the unit to check, null returns false - Returns:
- true if the unit can be added/subtracted, false if not
range
public ValueRange range(TemporalField field)
Gets the range of valid values for the specified field.The range object expresses the minimum and maximum valid values for a field. This instant is used to enhance the accuracy of the returned range. If it is not possible to return the range, because the field is not supported or for some other reason, an exception is thrown.
If the field is a
ChronoField
then the query is implemented here. Thesupported fields
will return appropriate range instances. All otherChronoField
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.rangeRefinedBy(TemporalAccessor)
passingthis
as the argument. Whether the range can be obtained is determined by the field.- Specified by:
-
range
in interfaceTemporalAccessor
- Parameters:
-
field
- the field to query the range for, not null - Returns:
- the range of valid values for the field, not null
- Throws:
-
DateTimeException
- if the range for the field cannot be obtained -
UnsupportedTemporalTypeException
- if the field is not supported
get
public int get(TemporalField field)
Gets the value of the specified field from this instant as anint
.This queries this instant for the value of the specified field. The returned value will always be within the valid range of values for the field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown.
If the field is a
ChronoField
then the query is implemented here. Thesupported fields
will return valid values based on this date-time, exceptINSTANT_SECONDS
which is too large to fit in anint
and throws aDateTimeException
. All otherChronoField
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.getFrom(TemporalAccessor)
passingthis
as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.- Specified by:
-
get
in interfaceTemporalAccessor
- Parameters:
-
field
- the field to get, not null - Returns:
- the value for the field
- Throws:
-
DateTimeException
- if a value for the field cannot be obtained or the value is outside the range of valid values for the field -
UnsupportedTemporalTypeException
- if the field is not supported or the range of values exceeds anint
-
ArithmeticException
- if numeric overflow occurs
getLong
public long getLong(TemporalField field)
Gets the value of the specified field from this instant as along
.This queries this instant for the value of the specified field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown.
If the field is a
ChronoField
then the query is implemented here. Thesupported fields
will return valid values based on this date-time. All otherChronoField
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.getFrom(TemporalAccessor)
passingthis
as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.- Specified by:
-
getLong
in interfaceTemporalAccessor
- Parameters:
-
field
- the field to get, not null - Returns:
- the value for the field
- Throws:
-
DateTimeException
- if a value for the field cannot be obtained -
UnsupportedTemporalTypeException
- if the field is not supported -
ArithmeticException
- if numeric overflow occurs
getEpochSecond
public long getEpochSecond()
Gets the number of seconds from the Java epoch of 1970-01-01T00:00:00Z.The epoch second count is a simple incrementing count of seconds where second 0 is 1970-01-01T00:00:00Z. The nanosecond part of the day is returned by
getNanosOfSecond
.- Returns:
- the seconds from the epoch of 1970-01-01T00:00:00Z
getNano
public int getNano()
Gets the number of nanoseconds, later along the time-line, from the start of the second.The nanosecond-of-second value measures the total number of nanoseconds from the second returned by
getEpochSecond
.- Returns:
- the nanoseconds within the second, always positive, never exceeds 999,999,999
with
public Instant with(TemporalAdjuster adjuster)
Returns an adjusted copy of this instant.This returns an
Instant
, based on this one, with the instant adjusted. The adjustment takes place using the specified adjuster strategy object. Read the documentation of the adjuster to understand what adjustment will be made.The result of this method is obtained by invoking the
TemporalAdjuster.adjustInto(Temporal)
method on the specified adjuster passingthis
as the argument.This instance is immutable and unaffected by this method call.
- Specified by:
-
with
in interfaceTemporal
- Parameters:
-
adjuster
- the adjuster to use, not null - Returns:
-
an
Instant
based onthis
with the adjustment made, not null - Throws:
-
DateTimeException
- if the adjustment cannot be made -
ArithmeticException
- if numeric overflow occurs
with
public Instant with(TemporalField field, long newValue)
Returns a copy of this instant with the specified field set to a new value.This returns an
Instant
, based on this one, with the value for the specified field changed. If it is not possible to set the value, because the field is not supported or for some other reason, an exception is thrown.If the field is a
ChronoField
then the adjustment is implemented here. The supported fields behave as follows:NANO_OF_SECOND
- Returns anInstant
with the specified nano-of-second. The epoch-second will be unchanged.MICRO_OF_SECOND
- Returns anInstant
with the nano-of-second replaced by the specified micro-of-second multiplied by 1,000. The epoch-second will be unchanged.MILLI_OF_SECOND
- Returns anInstant
with the nano-of-second replaced by the specified milli-of-second multiplied by 1,000,000. The epoch-second will be unchanged.INSTANT_SECONDS
- Returns anInstant
with the specified epoch-second. The nano-of-second will be unchanged.
In all cases, if the new value is outside the valid range of values for the field then a
DateTimeException
will be thrown.All other
ChronoField
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoField
, then the result of this method is obtained by invokingTemporalField.adjustInto(Temporal, long)
passingthis
as the argument. In this case, the field determines whether and how to adjust the instant.This instance is immutable and unaffected by this method call.
- Specified by:
-
with
in interfaceTemporal
- Parameters:
-
field
- the field to set in the result, not null -
newValue
- the new value of the field in the result - Returns:
-
an
Instant
based onthis
with the specified field set, not null - Throws:
-
DateTimeException
- if the field cannot be set -
UnsupportedTemporalTypeException
- if the field is not supported -
ArithmeticException
- if numeric overflow occurs
truncatedTo
public Instant truncatedTo(TemporalUnit unit)
Returns a copy of thisInstant
truncated to the specified unit.Truncating the instant returns a copy of the original with fields smaller than the specified unit set to zero. The fields are calculated on the basis of using a UTC offset as seen in
toString
. For example, truncating with theMINUTES
unit will round down to the nearest minute, setting the seconds and nanoseconds to zero.The unit must have a duration that divides into the length of a standard day without remainder. This includes all supplied time units on
ChronoUnit
andDAYS
. Other units throw an exception.This instance is immutable and unaffected by this method call.
- Parameters:
-
unit
- the unit to truncate to, not null - Returns:
-
an
Instant
based on this instant with the time truncated, not null - Throws:
-
DateTimeException
- if the unit is invalid for truncation -
UnsupportedTemporalTypeException
- if the unit is not supported
plus
public Instant plus(TemporalAmount amountToAdd)
Returns a copy of this instant with the specified amount added.This returns an
Instant
, based on this one, with the specified amount added. The amount is typicallyDuration
but may be any other type implementing theTemporalAmount
interface.The calculation is delegated to the amount object by calling
TemporalAmount.addTo(Temporal)
. The amount implementation is free to implement the addition in any way it wishes, however it typically calls back toplus(long, TemporalUnit)
. Consult the documentation of the amount implementation to determine if it can be successfully added.This instance is immutable and unaffected by this method call.
- Specified by:
-
plus
in interfaceTemporal
- Parameters:
-
amountToAdd
- the amount to add, not null - Returns:
-
an
Instant
based on this instant with the addition made, not null - Throws:
-
DateTimeException
- if the addition cannot be made -
ArithmeticException
- if numeric overflow occurs
plus
public Instant plus(long amountToAdd, TemporalUnit unit)
Returns a copy of this instant with the specified amount added.This returns an
Instant
, based on this one, with the amount in terms of the unit added. If it is not possible to add the amount, because the unit is not supported or for some other reason, an exception is thrown.If the field is a
ChronoUnit
then the addition is implemented here. The supported fields behave as follows:NANOS
- Returns aInstant
with the specified number of nanoseconds added. This is equivalent toplusNanos(long)
.MICROS
- Returns aInstant
with the specified number of microseconds added. This is equivalent toplusNanos(long)
with the amount multiplied by 1,000.MILLIS
- Returns aInstant
with the specified number of milliseconds added. This is equivalent toplusNanos(long)
with the amount multiplied by 1,000,000.SECONDS
- Returns aInstant
with the specified number of seconds added. This is equivalent toplusSeconds(long)
.MINUTES
- Returns aInstant
with the specified number of minutes added. This is equivalent toplusSeconds(long)
with the amount multiplied by 60.HOURS
- Returns aInstant
with the specified number of hours added. This is equivalent toplusSeconds(long)
with the amount multiplied by 3,600.HALF_DAYS
- Returns aInstant
with the specified number of half-days added. This is equivalent toplusSeconds(long)
with the amount multiplied by 43,200 (12 hours).DAYS
- Returns aInstant
with the specified number of days added. This is equivalent toplusSeconds(long)
with the amount multiplied by 86,400 (24 hours).
All other
ChronoUnit
instances will throw anUnsupportedTemporalTypeException
.If the field is not a
ChronoUnit
, then the result of this method is obtained by invokingTemporalUnit.addTo(Temporal, long)
passingthis
as the argument. In this case, the unit determines whether and how to perform the addition.This instance is immutable and unaffected by this method call.
- Specified by:
-
plus
in interfaceTemporal
- Parameters:
-
amountToAdd
- the amount of the unit to add to the result, may be negative -
unit
- the unit of the amount to add, not null - Returns:
-
an
Instant
based on this instant with the specified amount added, not null - Throws:
-
DateTimeException
- if the addition cannot be made -
UnsupportedTemporalTypeException
- if the unit is not supported -
ArithmeticException
- if numeric overflow occurs
plusSeconds
public Instant plusSeconds(long secondsToAdd)
Returns a copy of this instant with the specified duration in seconds added.This instance is immutable and unaffected by this method call.
- Parameters:
-
secondsToAdd
- the seconds to add, positive or negative - Returns:
-
an
Instant
based on this instant with the specified seconds added, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
plusMillis
public Instant plusMillis(long millisToAdd)
Returns a copy of this instant with the specified duration in milliseconds added.This instance is immutable and unaffected by this method call.
- Parameters:
-
millisToAdd
- the milliseconds to add, positive or negative - Returns:
-
an
Instant
based on this instant with the specified milliseconds added, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
plusNanos
public Instant plusNanos(long nanosToAdd)
Returns a copy of this instant with the specified duration in nanoseconds added.This instance is immutable and unaffected by this method call.
- Parameters:
-
nanosToAdd
- the nanoseconds to add, positive or negative - Returns:
-
an
Instant
based on this instant with the specified nanoseconds added, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
minus
public Instant minus(TemporalAmount amountToSubtract)
Returns a copy of this instant with the specified amount subtracted.This returns an
Instant
, based on this one, with the specified amount subtracted. The amount is typicallyDuration
but may be any other type implementing theTemporalAmount
interface.The calculation is delegated to the amount object by calling
TemporalAmount.subtractFrom(Temporal)
. The amount implementation is free to implement the subtraction in any way it wishes, however it typically calls back tominus(long, TemporalUnit)
. Consult the documentation of the amount implementation to determine if it can be successfully subtracted.This instance is immutable and unaffected by this method call.
- Specified by:
-
minus
in interfaceTemporal
- Parameters:
-
amountToSubtract
- the amount to subtract, not null - Returns:
-
an
Instant
based on this instant with the subtraction made, not null - Throws:
-
DateTimeException
- if the subtraction cannot be made -
ArithmeticException
- if numeric overflow occurs
minus
public Instant minus(long amountToSubtract, TemporalUnit unit)
Returns a copy of this instant with the specified amount subtracted.This returns a
Instant
, based on this one, with the amount in terms of the unit subtracted. If it is not possible to subtract the amount, because the unit is not supported or for some other reason, an exception is thrown.This method is equivalent to
plus(long, TemporalUnit)
with the amount negated. See that method for a full description of how addition, and thus subtraction, works.This instance is immutable and unaffected by this method call.
- Specified by:
-
minus
in interfaceTemporal
- Parameters:
-
amountToSubtract
- the amount of the unit to subtract from the result, may be negative -
unit
- the unit of the amount to subtract, not null - Returns:
-
an
Instant
based on this instant with the specified amount subtracted, not null - Throws:
-
DateTimeException
- if the subtraction cannot be made -
UnsupportedTemporalTypeException
- if the unit is not supported -
ArithmeticException
- if numeric overflow occurs
minusSeconds
public Instant minusSeconds(long secondsToSubtract)
Returns a copy of this instant with the specified duration in seconds subtracted.This instance is immutable and unaffected by this method call.
- Parameters:
-
secondsToSubtract
- the seconds to subtract, positive or negative - Returns:
-
an
Instant
based on this instant with the specified seconds subtracted, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
minusMillis
public Instant minusMillis(long millisToSubtract)
Returns a copy of this instant with the specified duration in milliseconds subtracted.This instance is immutable and unaffected by this method call.
- Parameters:
-
millisToSubtract
- the milliseconds to subtract, positive or negative - Returns:
-
an
Instant
based on this instant with the specified milliseconds subtracted, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
minusNanos
public Instant minusNanos(long nanosToSubtract)
Returns a copy of this instant with the specified duration in nanoseconds subtracted.This instance is immutable and unaffected by this method call.
- Parameters:
-
nanosToSubtract
- the nanoseconds to subtract, positive or negative - Returns:
-
an
Instant
based on this instant with the specified nanoseconds subtracted, not null - Throws:
-
DateTimeException
- if the result exceeds the maximum or minimum instant -
ArithmeticException
- if numeric overflow occurs
query
public <R> R query(TemporalQuery<R> query)
Queries this instant using the specified query.This queries this instant using the specified query strategy object. The
TemporalQuery
object defines the logic to be used to obtain the result. Read the documentation of the query to understand what the result of this method will be.The result of this method is obtained by invoking the
TemporalQuery.queryFrom(TemporalAccessor)
method on the specified query passingthis
as the argument.- Specified by:
-
query
in interfaceTemporalAccessor
- Type Parameters:
-
R
- the type of the result - Parameters:
-
query
- the query to invoke, not null - Returns:
- the query result, null may be returned (defined by the query)
- Throws:
-
DateTimeException
- if unable to query (defined by the query) -
ArithmeticException
- if numeric overflow occurs (defined by the query)
adjustInto
public Temporal adjustInto(Temporal temporal)
Adjusts the specified temporal object to have this instant.This returns a temporal object of the same observable type as the input with the instant changed to be the same as this.
The adjustment is equivalent to using
Temporal.with(TemporalField, long)
twice, passingChronoField.INSTANT_SECONDS
andChronoField.NANO_OF_SECOND
as the fields.In most cases, it is clearer to reverse the calling pattern by using
Temporal.with(TemporalAdjuster)
:// these two lines are equivalent, but the second approach is recommended temporal = thisInstant.adjustInto(temporal); temporal = temporal.with(thisInstant);
This instance is immutable and unaffected by this method call.
- Specified by:
-
adjustInto
in interfaceTemporalAdjuster
- Parameters:
-
temporal
- the target object to be adjusted, not null - Returns:
- the adjusted object, not null
- Throws:
-
DateTimeException
- if unable to make the adjustment -
ArithmeticException
- if numeric overflow occurs
until
public long until(Temporal endExclusive, TemporalUnit unit)
Calculates the amount of time until another instant in terms of the specified unit.This calculates the amount of time between two
Instant
objects in terms of a singleTemporalUnit
. The start and end points arethis
and the specified instant. The result will be negative if the end is before the start. The calculation returns a whole number, representing the number of complete units between the two instants. TheTemporal
passed to this method is converted to aInstant
usingfrom(TemporalAccessor)
. For example, the amount in days between two dates can be calculated usingstartInstant.until(endInstant, SECONDS)
.There are two equivalent ways of using this method. The first is to invoke this method. The second is to use
TemporalUnit.between(Temporal, Temporal)
:// these two lines are equivalent amount = start.until(end, SECONDS); amount = SECONDS.between(start, end);
The choice should be made based on which makes the code more readable.The calculation is implemented in this method for
ChronoUnit
. The unitsNANOS
,MICROS
,MILLIS
,SECONDS
,MINUTES
,HOURS
,HALF_DAYS
andDAYS
are supported. OtherChronoUnit
values will throw an exception.If the unit is not a
ChronoUnit
, then the result of this method is obtained by invokingTemporalUnit.between(Temporal, Temporal)
passingthis
as the first argument and the converted input temporal as the second argument.This instance is immutable and unaffected by this method call.
- Specified by:
-
until
in interfaceTemporal
- Parameters:
-
endExclusive
- the end date, exclusive, which is converted to anInstant
, not null -
unit
- the unit to measure the amount in, not null - Returns:
- the amount of time between this instant and the end instant
- Throws:
-
DateTimeException
- if the amount cannot be calculated, or the end temporal cannot be converted to anInstant
-
UnsupportedTemporalTypeException
- if the unit is not supported -
ArithmeticException
- if numeric overflow occurs
atOffset
public OffsetDateTime atOffset(ZoneOffset offset)
Combines this instant with an offset to create anOffsetDateTime
.This returns an
OffsetDateTime
formed from this instant at the specified offset from UTC/Greenwich. An exception will be thrown if the instant is too large to fit into an offset date-time.This method is equivalent to
OffsetDateTime.ofInstant(this, offset)
.- Parameters:
-
offset
- the offset to combine with, not null - Returns:
- the offset date-time formed from this instant and the specified offset, not null
- Throws:
-
DateTimeException
- if the result exceeds the supported range
atZone
public ZonedDateTime atZone(ZoneId zone)
Combines this instant with a time-zone to create aZonedDateTime
.This returns an
ZonedDateTime
formed from this instant at the specified time-zone. An exception will be thrown if the instant is too large to fit into a zoned date-time.This method is equivalent to
ZonedDateTime.ofInstant(this, zone)
.- Parameters:
-
zone
- the zone to combine with, not null - Returns:
- the zoned date-time formed from this instant and the specified zone, not null
- Throws:
-
DateTimeException
- if the result exceeds the supported range
toEpochMilli
public long toEpochMilli()
Converts this instant to the number of milliseconds from the epoch of 1970-01-01T00:00:00Z.If this instant represents a point on the time-line too far in the future or past to fit in a
long
milliseconds, then an exception is thrown.If this instant has greater than millisecond precision, then the conversion will drop any excess precision information as though the amount in nanoseconds was subject to integer division by one million.
- Returns:
- the number of milliseconds since the epoch of 1970-01-01T00:00:00Z
- Throws:
-
ArithmeticException
- if numeric overflow occurs
compareTo
public int compareTo(Instant otherInstant)
Compares this instant to the specified instant.The comparison is based on the time-line position of the instants. It is "consistent with equals", as defined by
Comparable
.- Specified by:
-
compareTo
in interfaceComparable<Instant>
- Parameters:
-
otherInstant
- the other instant to compare to, not null - Returns:
- the comparator value, negative if less, positive if greater
- Throws:
-
NullPointerException
- if otherInstant is null
isAfter
public boolean isAfter(Instant otherInstant)
Checks if this instant is after the specified instant.The comparison is based on the time-line position of the instants.
- Parameters:
-
otherInstant
- the other instant to compare to, not null - Returns:
- true if this instant is after the specified instant
- Throws:
-
NullPointerException
- if otherInstant is null
isBefore
public boolean isBefore(Instant otherInstant)
Checks if this instant is before the specified instant.The comparison is based on the time-line position of the instants.
- Parameters:
-
otherInstant
- the other instant to compare to, not null - Returns:
- true if this instant is before the specified instant
- Throws:
-
NullPointerException
- if otherInstant is null
equals
public boolean equals(Object otherInstant)
Checks if this instant is equal to the specified instant.The comparison is based on the time-line position of the instants.
- Overrides:
-
equals
in classObject
- Parameters:
-
otherInstant
- the other instant, null returns false - Returns:
- true if the other instant is equal to this one
- See Also:
-
Object.hashCode()
,HashMap
hashCode
public int hashCode()
Returns a hash code for this instant.- Overrides:
-
hashCode
in classObject
- Returns:
- a suitable hash code
- See Also:
-
Object.equals(java.lang.Object)
,System.identityHashCode(java.lang.Object)
toString
public String toString()
A string representation of this instant using ISO-8601 representation.The format used is the same as
DateTimeFormatter.ISO_INSTANT
.
-
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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