Adjusts the specified temporal object to have this year-month.
Adjusts the specified temporal object to have this year-month.
This returns a temporal object of the same observable type as the input with the year and month changed to be the same as this.
The adjustment is equivalent to using long)
passing ChronoField#PROLEPTIC_MONTH
as the field.
If the specified temporal object does not use the ISO calendar system then
a DateTimeException
is thrown.
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 = thisYearMonth.adjustInto(temporal); temporal = temporal.with(thisYearMonth);
This instance is immutable and unaffected by this method call.
the target object to be adjusted, not null
the adjusted object, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if unable to make the adjustment
Combines this year-month with a day-of-month to create a LocalDate
.
Combines this year-month with a day-of-month to create a LocalDate
.
This returns a LocalDate
formed from this year-month and the specified day-of-month.
The day-of-month value must be valid for the year-month.
This method can be used as part of a chain to produce a date:
LocalDate date = year.atMonth(month).atDay(day);
the day-of-month to use, from 1 to 31
the date formed from this year-month and the specified day, not null
DateTimeException
if the day is invalid for the year-month
#isValidDay(int)
Returns a LocalDate
at the end of the month.
Returns a LocalDate
at the end of the month.
This returns a LocalDate
based on this year-month.
The day-of-month is set to the last valid day of the month, taking
into account leap years.
This method can be used as part of a chain to produce a date:
LocalDate date = year.atMonth(month).atEndOfMonth();
the last valid date of this year-month, not null
Compares this year-month to another year-month.
Compares this year-month to another year-month.
The comparison is based first on the value of the year, then on the value of the month.
It is "consistent with equals", as defined by Comparable
.
the other year-month to compare to, not null
the comparator value, negative if less, positive if greater
Checks if this year-month is equal to another year-month.
Checks if this year-month is equal to another year-month.
The comparison is based on the time-line position of the year-months.
the object to check, null returns false
true if this is equal to the other year-month
Outputs this year-month as a String
using the formatter.
Outputs this year-month as a String
using the formatter.
This year-month will be passed to the formatter
print method
.
the formatter to use, not null
the formatted year-month string, not null
DateTimeException
if an error occurs during printing
Gets the value of the specified field from this year-month as an int
.
Gets the value of the specified field from this year-month as an int
.
This queries this year-month for the value for 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.
The supported fields
will return valid
values based on this year-month, except EPOCH_MONTH
which is too
large to fit in an int
and throw a DateTimeException
.
All other ChronoField
instances will throw a DateTimeException
.
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. Whether the value can be obtained,
and what the value represents, is determined by the field.
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
Gets the value of the specified field from this year-month as a long
.
Gets the value of the specified field from this year-month as a long
.
This queries this year-month for the value for 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.
The supported fields
will return valid
values based on this year-month.
All other ChronoField
instances will throw a DateTimeException
.
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. Whether the value can be obtained,
and what the value represents, is determined by the field.
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
Gets the month-of-year field using the Month
enum.
Gets the month-of-year field using the Month
enum.
This method returns the enum Month
for the month.
This avoids confusion as to what int
values mean.
If you need access to the primitive int
value then the enum
provides the int value
.
the month-of-year, not null
Gets the month-of-year field from 1 to 12.
Gets the month-of-year field from 1 to 12.
This method returns the month as an int
from 1 to 12.
Application code is frequently clearer if the enum Month
is used by calling #getMonth()
.
the month-of-year, from 1 to 12
#getMonth()
Gets the year field.
Gets the year field.
This method returns the primitive int
value for the year.
The year returned by this method is proleptic as per get(YEAR)
.
the year, from MIN_YEAR to MAX_YEAR
A hash code for this year-month.
A hash code for this year-month.
a suitable hash code
Is this year-month after the specified year-month.
Is this year-month after the specified year-month.
the other year-month to compare to, not null
true if this is after the specified year-month
Is this year-month before the specified year-month.
Is this year-month before the specified year-month.
the other year-month to compare to, not null
true if this point is before the specified year-month
Checks if the year is a leap year, according to the ISO proleptic calendar system rules.
Checks if the year is a leap year, according to the ISO proleptic calendar system rules.
This method applies the current rules for leap years across the whole time-line. In general, a year is a leap year if it is divisible by four without remainder. However, years divisible by 100, are not leap years, with the exception of years divisible by 400 which are.
For example, 1904 is a leap year it is divisible by 4. 1900 was not a leap year as it is divisible by 100, however 2000 was a leap year as it is divisible by 400.
The calculation is proleptic - applying the same rules into the far future and far past. This is historically inaccurate, but is correct for the ISO-8601 standard.
true if the year is leap, false otherwise
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 this year-month can be queried for the specified field.
If false, then calling the range
and
get
methods will throw an exception.
If the field is a ChronoField
then the query is implemented here.
The supported fields
will return valid
values based on this date-time.
The supported fields are:
MONTH_OF_YEAR
EPOCH_MONTH
YEAR_OF_ERA
YEAR
ERA
All other ChronoField
instances will return 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.
Whether the field is supported is determined by the field.
the field to check, null returns false
true if the field is supported on this year-month, false if not
Checks if the day-of-month is valid for this year-month.
Checks if the day-of-month is valid for this year-month.
This method checks whether this year and month and the input day form a valid date.
the day-of-month to validate, from 1 to 31, invalid value returns false
true if the day is valid for this year-month
Returns the length of the month, taking account of the year.
Returns the length of the month, taking account of the year.
This returns the length of the month in days. For example, a date in January would return 31.
the length of the month in days, from 28 to 31
Returns the length of the year.
Returns the length of the year.
This returns the length of the year in days, either 365 or 366.
366 if the year is leap, 365 otherwise
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
{ @inheritDoc}
DateTimeException
{ @inheritDoc}
Returns a copy of this year-month with the specified period subtracted.
Returns a copy of this year-month with the specified period subtracted.
This method returns a new year-month based on this year-month with the specified period subtracted.
The subtractor is typically Period
but may be any other type implementing
the TemporalAmount
interface.
The calculation is delegated to the specified adjuster, which typically calls
back to TemporalUnit)
.
This instance is immutable and unaffected by this method call.
the amount to aubtract, not null
a { @code YearMonth} based on this year-month with the subtraction made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the subtraction cannot be made
Returns a copy of this year-month with the specified period in months subtracted.
Returns a copy of this year-month with the specified period in months subtracted.
This instance is immutable and unaffected by this method call.
the months to subtract, may be negative
a { @code YearMonth} based on this year-month with the months subtracted, not null
DateTimeException
if the result exceeds the supported range
Returns a copy of this year-month with the specified period in years subtracted.
Returns a copy of this year-month with the specified period in years subtracted.
This instance is immutable and unaffected by this method call.
the years to subtract, may be negative
a { @code YearMonth} based on this year-month with the years subtracted, not null
DateTimeException
if the result exceeds the supported range
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
{ @inheritDoc}
DateTimeException
{ @inheritDoc}
Returns a copy of this year-month with the specified period added.
Returns a copy of this year-month with the specified period added.
This method returns a new year-month based on this year-month with the specified period added.
The adder is typically Period
but may be any other type implementing
the TemporalAmount
interface.
The calculation is delegated to the specified adjuster, which typically calls
back to TemporalUnit)
.
This instance is immutable and unaffected by this method call.
the amount to add, not null
a { @code YearMonth} based on this year-month with the addition made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the addition cannot be made
Returns a copy of this year-month with the specified period in months added.
Returns a copy of this year-month with the specified period in months added.
This instance is immutable and unaffected by this method call.
the months to add, may be negative
a { @code YearMonth} based on this year-month with the months added, not null
DateTimeException
if the result exceeds the supported range
Returns a copy of this year-month with the specified period in years added.
Returns a copy of this year-month with the specified period in years added.
This instance is immutable and unaffected by this method call.
the years to add, may be negative
a { @code YearMonth} based on this year-month with the years added, not null
DateTimeException
if the result exceeds the supported range
Queries this year-month using the specified query.
Queries this year-month using the specified query.
This queries this year-month 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 passing this
as the argument.
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 (defined by the query)
DateTimeException
if unable to query (defined by the query)
Gets the range of valid values for the specified 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 year-month 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.
The supported fields
will return
appropriate range instances.
All other ChronoField
instances will throw a DateTimeException
.
If the field is not a ChronoField
, then the result of this method
is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessor)
passing this
as the argument.
Whether the range can be obtained is determined by the field.
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
Outputs this year-month as a String
, such as 2007-12
.
Outputs this year-month as a String
, such as 2007-12
.
The output will be in the format yyyy-MM
:
a string representation of this year-month, not null
Calculates the period between this year-month and another year-month in terms of the specified unit.
Calculates the period between this year-month and another year-month in terms of the specified unit.
This calculates the period between two year-months in terms of a single unit.
The start and end points are this
and the specified year-month.
The result will be negative if the end is before the start.
The Temporal
passed to this method must be a YearMonth
.
For example, the period in years between two year-months can be calculated
using startYearMonth.until(endYearMonth, YEARS)
.
The calculation returns a whole number, representing the number of complete units between the two year-months. For example, the period in decades between 2012-06 and 2032-05 will only be one decade as it is one month short of two decades.
This method operates in association with TemporalUnit#between
.
The result of this method is a long
representing the amount of
the specified unit. By contrast, the result of between
is an
object that can be used directly in addition/subtraction:
val period: Long = start.until(end, YEARS); // this method dateTime.plus(YEARS.between(start, end)); // use in plus/minus
The calculation is implemented in this method for ChronoUnit
.
The units MONTHS
, YEARS
, DECADES
,
CENTURIES
, MILLENNIA
and ERAS
are supported.
Other ChronoUnit
values will throw an exception.
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.
This instance is immutable and unaffected by this method call.
the end year-month, which is converted to a { @code YearMonth}, not null
the unit to measure the period in, not null
the amount of the period between this year-month and the end year-month
ArithmeticException
if numeric overflow occurs
DateTimeException
if the period cannot be calculated
Returns a copy of this year-month with the specified field set to a new value.
Returns a copy of this year-month with the specified field set to a new value.
This returns a new YearMonth
, based on this one, with the value
for the specified field changed.
This can be used to change any supported field, such as the year or month.
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:
MONTH_OF_YEAR
-
Returns a YearMonth
with the specified month-of-year.
The year will be unchanged.PROLEPTIC_MONTH
-
Returns a YearMonth
with the specified proleptic-month.
This completely replaces the year and month of this object.YEAR_OF_ERA
-
Returns a YearMonth
with the specified year-of-era
The month and era will be unchanged.YEAR
-
Returns a YearMonth
with the specified year.
The month will be unchanged.ERA
-
Returns a YearMonth
with the specified era.
The month and year-of-era 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 a DateTimeException
.
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 argument. In this case, the field determines
whether and how to adjust the instant.
This instance is immutable and unaffected by this method call.
the field to set in the result, not null
the new value of the field in the result
a { @code YearMonth} based on { @code this} with the specified field set, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the field cannot be set
Returns an adjusted copy of this year-month.
Returns an adjusted copy of this year-month.
This returns a new YearMonth
, based on this one, with the year-month adjusted.
The adjustment takes place using the specified adjuster strategy object.
Read the documentation of the adjuster to understand what adjustment will be made.
A simple adjuster might simply set the one of the fields, such as the year field. A more complex adjuster might set the year-month to the next month that Halley's comet will pass the Earth.
The result of this method is obtained by invoking the
TemporalAdjuster#adjustInto(Temporal)
method on the
specified adjuster passing this
as the argument.
This instance is immutable and unaffected by this method call.
the adjuster to use, not null
a { @code YearMonth} based on { @code this} with the adjustment made, not null
ArithmeticException
if numeric overflow occurs
DateTimeException
if the adjustment cannot be made
Returns a copy of this YearMonth
with the month-of-year altered.
Returns a copy of this YearMonth
with the month-of-year altered.
This instance is immutable and unaffected by this method call.
the month-of-year to set in the returned year-month, from 1 (January) to 12 (December)
a { @code YearMonth} based on this year-month with the requested month, not null
DateTimeException
if the month-of-year value is invalid
Returns a copy of this YearMonth
with the year altered.
Returns a copy of this YearMonth
with the year altered.
This instance is immutable and unaffected by this method call.
the year to set in the returned year-month, from MIN_YEAR to MAX_YEAR
a { @code YearMonth} based on this year-month with the requested year, not null
DateTimeException
if the year value is invalid