ChronoLocalDate

adjustInto

public Temporal adjustInto (Temporal temporal)

Adjusts the specified temporal object to have the same date as this object.

This returns a temporal object of the same observable type as the input with the date changed to be the same as this.

The adjustment is equivalent to using Temporal.with(TemporalField, long) passing ChronoField.EPOCH_DAY as the field.

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 = thisLocalDate.adjustInto(temporal);
   temporal = temporal.with(thisLocalDate);
 

This instance is immutable and unaffected by this method call.

atTime

public ChronoLocalDateTime<?> atTime (LocalTime localTime)

Combines this date with a time to create a ChronoLocalDateTime.

This returns a ChronoLocalDateTime formed from this date at the specified time. All possible combinations of date and time are valid.

compareTo

public int compareTo (ChronoLocalDate other)

Compares this date to another date, including the chronology.

The comparison is based first on the underlying time-line date, then on the chronology. It is "consistent with equals", as defined by Comparable.

For example, the following is the comparator order:

1. 2012-12-03 (ISO)
2. 2012-12-04 (ISO)
3. 2555-12-04 (ThaiBuddhist)
4. 2012-12-05 (ISO)

If all the date objects being compared are in the same chronology, then the additional chronology stage is not required and only the local date is used. To compare the dates of two TemporalAccessor instances, including dates in two different chronologies, use ChronoField.EPOCH_DAY as a comparator.

This default implementation performs the comparison defined above.

equals

public abstract boolean equals (Object obj)

Checks if this date is equal to another date, including the chronology.

Compares this date with another ensuring that the date and chronology are the same.

To compare the dates of two TemporalAccessor instances, including dates in two different chronologies, use ChronoField.EPOCH_DAY as a comparator.

format

public String format (DateTimeFormatter formatter)

Formats this date using the specified formatter.

This date will be passed to the formatter to produce a string.

The default implementation must behave as follows:

  return formatter.format(this);
 

from

public static ChronoLocalDate from (TemporalAccessor temporal)

Obtains an instance of ChronoLocalDate from a temporal object.

This obtains a local date based on the specified temporal. A TemporalAccessor represents an arbitrary set of date and time information, which this factory converts to an instance of ChronoLocalDate.

The conversion extracts and combines the chronology and the date from the temporal object. The behavior is equivalent to using Chronology.date(TemporalAccessor) with the extracted chronology. Implementations are permitted to perform optimizations such as accessing those fields that are equivalent to the relevant objects.

This method matches the signature of the functional interface TemporalQuery allowing it to be used as a query via method reference, ChronoLocalDate::from.

getChronology

public abstract Chronology getChronology ()

Gets the chronology of this date.

The Chronology represents the calendar system in use. The era and other fields in ChronoField are defined by the chronology.

getEra

public Era getEra ()

Gets the era, as defined by the chronology.

The era is, conceptually, the largest division of the time-line. Most calendar systems have a single epoch dividing the time-line into two eras. However, some have multiple eras, such as one for the reign of each leader. The exact meaning is determined by the Chronology.

All correctly implemented Era classes are singletons, thus it is valid code to write date.getEra() == SomeChrono.ERA_NAME).

This default implementation uses Chronology.eraOf(int).

hashCode

public abstract int hashCode ()

A hash code for this date.

isAfter

public boolean isAfter (ChronoLocalDate other)

Checks if this date is after the specified date ignoring the chronology.

This method differs from the comparison in Comparable.compareTo(T) in that it only compares the underlying date and not the chronology. This allows dates in different calendar systems to be compared based on the time-line position. This is equivalent to using date1.toEpochDay() > date2.toEpochDay().

This default implementation performs the comparison based on the epoch-day.

isBefore

public boolean isBefore (ChronoLocalDate other)

Checks if this date is before the specified date ignoring the chronology.

This method differs from the comparison in Comparable.compareTo(T) in that it only compares the underlying date and not the chronology. This allows dates in different calendar systems to be compared based on the time-line position. This is equivalent to using date1.toEpochDay() < date2.toEpochDay().

This default implementation performs the comparison based on the epoch-day.

isEqual

public boolean isEqual (ChronoLocalDate other)

Checks if this date is equal to the specified date ignoring the chronology.

This method differs from the comparison in Comparable.compareTo(T) in that it only compares the underlying date and not the chronology. This allows dates in different calendar systems to be compared based on the time-line position. This is equivalent to using date1.toEpochDay() == date2.toEpochDay().

This default implementation performs the comparison based on the epoch-day.

isLeapYear

public boolean isLeapYear ()

Checks if the year is a leap year, as defined by the calendar system.

A leap-year is a year of a longer length than normal. The exact meaning is determined by the chronology with the constraint that a leap-year must imply a year-length longer than a non leap-year.

This default implementation uses Chronology.isLeapYear(long).

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. If false, then calling the plus(long, java.time.temporal.TemporalUnit) and minus methods will throw an exception.

The set of supported units is defined by the chronology and normally includes all ChronoUnit date units except FOREVER.

If the unit is not a ChronoUnit, then the result of this method is obtained by invoking TemporalUnit.isSupportedBy(Temporal) passing this as the argument. Whether the unit is supported is determined by the unit.

isSupported

public boolean isSupported (TemporalField field)

Checks if the specified field is supported.

This checks if the specified field can be queried on this date. If false, then calling the range, get and with(java.time.temporal.TemporalField, long) methods will throw an exception.

The set of supported fields is defined by the chronology and normally includes all ChronoField date fields.

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.

lengthOfMonth

public abstract int lengthOfMonth ()

Returns the length of the month represented by this date, as defined by the calendar system.

This returns the length of the month in days.

lengthOfYear

public int lengthOfYear ()

Returns the length of the year represented by this date, as defined by the calendar system.

This returns the length of the year in days.

The default implementation uses isLeapYear() and returns 365 or 366.

minus

public ChronoLocalDate 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 Period but may be any other type implementing the TemporalAmount interface, such as Duration.

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 plus followed by minus is not guaranteed to return the same date-time.

minus

public ChronoLocalDate 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 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.

plus

public ChronoLocalDate 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 Period but may be any other type implementing the TemporalAmount interface, such as Duration.

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 plus followed by minus is not guaranteed to return the same date-time.

plus

public ChronoLocalDate 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 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.

query

public R query (TemporalQuery<R> query)

Queries this date using the specified query.

This queries this date 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.

timeLineOrder

public static Comparator<ChronoLocalDate> timeLineOrder ()

Gets a comparator that compares ChronoLocalDate in time-line order ignoring the chronology.

This comparator differs from the comparison in Comparable.compareTo(T) in that it only compares the underlying date and not the chronology. This allows dates in different calendar systems to be compared based on the position of the date on the local time-line. The underlying comparison is equivalent to comparing the epoch-day.

toEpochDay

public long toEpochDay ()

Converts this date to the Epoch Day.

The Epoch Day count is a simple incrementing count of days where day 0 is 1970-01-01 (ISO). This definition is the same for all chronologies, enabling conversion.

This default implementation queries the EPOCH_DAY field.

toString

public abstract String toString ()

Outputs this date as a String.

The output will include the full local date.

until

public abstract long until (Temporal endExclusive, 
                TemporalUnit unit)

Calculates the amount of time until another date in terms of the specified unit.

This calculates the amount of time between two ChronoLocalDate objects in terms of a single TemporalUnit. The start and end points are this and the specified date. The result will be negative if the end is before the start. The Temporal passed to this method is converted to a ChronoLocalDate using Chronology.date(TemporalAccessor). The calculation returns a whole number, representing the number of complete units between the two dates. For example, the amount in days between two dates can be calculated using startDate.until(endDate, DAYS).

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, MONTHS);
   amount = MONTHS.between(start, end);
 

The calculation is implemented in this method for ChronoUnit. The units DAYS, WEEKS, MONTHS, YEARS, DECADES, CENTURIES, MILLENNIA and ERAS should be supported by all implementations. 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 converted input temporal as the second argument.

This instance is immutable and unaffected by this method call.

until

public abstract ChronoPeriod until (ChronoLocalDate endDateExclusive)

Calculates the period between this date and another date as a ChronoPeriod.

This calculates the period between two dates. All supplied chronologies calculate the period using years, months and days, however the ChronoPeriod API allows the period to be represented using other units.

The start and end points are this and the specified date. The result will be negative if the end is before the start. The negative sign will be the same in each of year, month and day.

The calculation is performed using the chronology of this date. If necessary, the input date will be converted to match.

This instance is immutable and unaffected by this method call.

with

public ChronoLocalDate 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 LocalDate, this could be used to set the year, month or day-of-month. 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 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.

with

public ChronoLocalDate 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 TemporalAdjusters. These include finding the "last day of the month" and "next Wednesday". The adjuster is responsible for handling special cases, such as the varying lengths of month and leap years.

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