Package org.threeten.bp.chrono

Class ChronoLocalDateTime<D extends ChronoLocalDate>

  • Type Parameters:
    D - the date type
    All Implemented Interfaces:
    Comparable<ChronoLocalDateTime<?>>, Temporal, TemporalAccessor, TemporalAdjuster
    Direct Known Subclasses:
    LocalDateTime
    public abstract class ChronoLocalDateTime<D extends ChronoLocalDate>
extends DefaultInterfaceTemporal
implements Temporal, TemporalAdjuster, Comparable<ChronoLocalDateTime<?>>
    A date-time without a time-zone in an arbitrary chronology, intended for advanced globalization use cases.

    Most applications should declare method signatures, fields and variables as LocalDateTime, not this interface.

    A ChronoLocalDateTime is the abstract representation of a local date-time where the Chronology chronology, or calendar system, is pluggable. The date-time is defined in terms of fields expressed by TemporalField, where most common implementations are defined in ChronoField. The chronology defines how the calendar system operates and the meaning of the standard fields.

    When to use this interface

    The design of the API encourages the use of LocalDateTime rather than this interface, even in the case where the application needs to deal with multiple calendar systems. The rationale for this is explored in detail in ChronoLocalDate.

    Ensure that the discussion in ChronoLocalDate has been read and understood before using 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. Subclasses should be Serializable wherever possible.

    In JDK 8, this is an interface with default methods. Since there are no default methods in JDK 7, an abstract class is used.

    • Constructor Detail

      • ChronoLocalDateTime

        public ChronoLocalDateTime()

    • Method Detail

      • from

        public static ChronoLocalDateTime<?> from​(TemporalAccessor temporal)
        Obtains an instance of ChronoLocalDateTime from a temporal object.

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

        The conversion extracts and combines the chronology and the date-time from the temporal object. The behavior is equivalent to using Chronology.localDateTime(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, ChronoLocalDateTime::from.

        Parameters:
        temporal - the temporal object to convert, not null
        Returns:
        the date-time, not null
        Throws:
        DateTimeException - if unable to convert to a ChronoLocalDateTime
        See Also:
        Chronology.localDateTime(TemporalAccessor)

      • getChronology

        public Chronology getChronology()
        Gets the chronology of this date-time.

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

        Returns:
        the chronology, not null

      • toLocalDate

        public abstract D toLocalDate()
        Gets the local date part of this date-time.

        This returns a local date with the same year, month and day as this date-time.

        Returns:
        the date part of this date-time, not null

      • toLocalTime

        public abstract LocalTime toLocalTime()
        Gets the local time part of this date-time.

        This returns a local time with the same hour, minute, second and nanosecond as this date-time.

        Returns:
        the time part of this date-time, not null

      • with

        public ChronoLocalDateTime<D> with​(TemporalAdjuster adjuster)
        Description copied from interface: Temporal
        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 TemporalAdjusters
  date = date.with(next(WEDNESDAY));   // static import from TemporalAdjusters and DayOfWeek

        Specification for implementors

        Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
        Specified by:
        with in interface Temporal
        Overrides:
        with in class DefaultInterfaceTemporal
        Parameters:
        adjuster - the adjuster to use, not null
        Returns:
        an object of the same type with the specified adjustment made, not null

      • with

        public abstract ChronoLocalDateTime<D> with​(TemporalField field,
                                            long newValue)
        Description copied from interface: Temporal
        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.

        Specification for implementors

        Implementations must check and handle all fields defined in ChronoField. If the field is supported, then the adjustment must be performed. If unsupported, then a DateTimeException must be thrown.

        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 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.

        Specified by:
        with in interface Temporal
        Parameters:
        field - the field to set in the result, not null
        newValue - the new value of the field in the result
        Returns:
        an object of the same type with the specified field set, not null

      • plus

        public ChronoLocalDateTime<D> plus​(TemporalAmount amount)
        Description copied from interface: Temporal
        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.

        Specification for implementors

        Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
        Specified by:
        plus in interface Temporal
        Overrides:
        plus in class DefaultInterfaceTemporal
        Parameters:
        amount - the amount to add, not null
        Returns:
        an object of the same type with the specified adjustment made, not null

      • plus

        public abstract ChronoLocalDateTime<D> plus​(long amountToAdd,
                                            TemporalUnit unit)
        Description copied from interface: Temporal
        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.

        Specification for implementors

        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.

        Specified by:
        plus in interface Temporal
        Parameters:
        amountToAdd - the amount of the specified unit to add, may be negative
        unit - the unit of the period to add, not null
        Returns:
        an object of the same type with the specified period added, not null

      • minus

        public ChronoLocalDateTime<D> minus​(TemporalAmount amount)
        Description copied from interface: Temporal
        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.

        Specification for implementors

        Implementations must not alter either this object. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable implementations.
        Specified by:
        minus in interface Temporal
        Overrides:
        minus in class DefaultInterfaceTemporal
        Parameters:
        amount - the amount to subtract, not null
        Returns:
        an object of the same type with the specified adjustment made, not null

      • minus

        public ChronoLocalDateTime<D> minus​(long amountToSubtract,
                                    TemporalUnit unit)
        Description copied from interface: Temporal
        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.

        Specification for implementors

        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.

        Specified by:
        minus in interface Temporal
        Overrides:
        minus in class DefaultInterfaceTemporal
        Parameters:
        amountToSubtract - the amount of the specified unit to subtract, may be negative
        unit - the unit of the period to subtract, not null
        Returns:
        an object of the same type with the specified period subtracted, not null

      • query

        public <R> R query​(TemporalQuery<R> query)
        Description copied from interface: TemporalAccessor
        Queries this date-time.

        This queries this date-time using the specified query strategy object.

        Queries are a key tool for extracting information from date-times. They exists to externalize the process of querying, permitting different approaches, as per the strategy design pattern. Examples might be a query that checks if the date is the day before February 29th in a leap year, or calculates the number of days to your next birthday.

        The most common query implementations are method references, such as LocalDate::from and ZoneId::from. Further implementations are on TemporalQueries. Queries may also be defined by applications.

        Specification for implementors

        Implementations of this method must behave as follows: 
           public <R> R query(TemporalQuery<R> type) {
     // only include an if statement if the implementation can return it
     if (query == TemporalQueries.zoneId())  return // the ZoneId
     if (query == TemporalQueries.chronology())  return // the Chrono
     if (query == TemporalQueries.precision())  return // the precision
     // call default method
     return super.query(query);
   }
        Specified by:
        query in interface TemporalAccessor
        Overrides:
        query in class DefaultInterfaceTemporalAccessor
        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)

      • adjustInto

        public Temporal adjustInto​(Temporal temporal)
        Description copied from interface: TemporalAdjuster
        Adjusts the specified temporal object.

        This adjusts the specified temporal object using the logic encapsulated in the implementing class. Examples might be an adjuster that sets the date avoiding weekends, or one that sets the date to the last day of the month.

        There are two equivalent ways of using this method. The first is to invoke this method directly. The second is to use Temporal.with(TemporalAdjuster): 

           // these two lines are equivalent, but the second approach is recommended
   temporal = thisAdjuster.adjustInto(temporal);
   temporal = temporal.with(thisAdjuster);
        It is recommended to use the second approach, with(TemporalAdjuster), as it is a lot clearer to read in code.

        Specification for implementors

        The implementation must take the input object and adjust it. The implementation defines the logic of the adjustment and is responsible for documenting that logic. It may use any method on Temporal to query the temporal object and perform the adjustment. The returned object must have the same observable type as the input object

        The input object must not be altered. Instead, an adjusted copy of the original must be returned. This provides equivalent, safe behavior for immutable and mutable temporal objects.

        The input temporal object may be in a calendar system other than ISO. Implementations may choose to document compatibility with other calendar systems, or reject non-ISO temporal objects by querying the chronology.

        This method may be called from multiple threads in parallel. It must be thread-safe when invoked.

        Specified by:
        adjustInto in interface TemporalAdjuster
        Parameters:
        temporal - the temporal object to adjust, not null
        Returns:
        an object of the same observable type with the adjustment made, not null

      • format

        public String format​(DateTimeFormatter formatter)
        Formats this date-time using the specified formatter.

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

        The default implementation must behave as follows: 

          return formatter.format(this);
        Parameters:
        formatter - the formatter to use, not null
        Returns:
        the formatted date-time string, not null
        Throws:
        DateTimeException - if an error occurs during printing

      • atZone

        public abstract ChronoZonedDateTime<D> atZone​(ZoneId zone)
        Combines this time with a time-zone to create a ChronoZonedDateTime.

        This returns a ChronoZonedDateTime formed from this date-time at the specified time-zone. The result will match this date-time as closely as possible. Time-zone rules, such as daylight savings, mean that not every local date-time is valid for the specified zone, thus the local date-time may be adjusted.

        The local date-time is resolved to a single instant on the time-line. This is achieved by finding a valid offset from UTC/Greenwich for the local date-time as defined by the rules of the zone ID.

        In most cases, there is only one valid offset for a local date-time. In the case of an overlap, where clocks are set back, there are two valid offsets. This method uses the earlier offset typically corresponding to "summer".

        In the case of a gap, where clocks jump forward, there is no valid offset. Instead, the local date-time is adjusted to be later by the length of the gap. For a typical one hour daylight savings change, the local date-time will be moved one hour later into the offset typically corresponding to "summer".

        To obtain the later offset during an overlap, call ChronoZonedDateTime.withLaterOffsetAtOverlap() on the result of this method.

        Parameters:
        zone - the time-zone to use, not null
        Returns:
        the zoned date-time formed from this date-time, not null

      • toInstant

        public Instant toInstant​(ZoneOffset offset)
        Converts this date-time to an Instant.

        This combines this local date-time and the specified offset to form an Instant.

        Parameters:
        offset - the offset to use for the conversion, not null
        Returns:
        an Instant representing the same instant, not null

      • toEpochSecond

        public long toEpochSecond​(ZoneOffset offset)
        Converts this date-time to the number of seconds from the epoch of 1970-01-01T00:00:00Z.

        This combines this local date-time and the specified offset to calculate the epoch-second value, which is the number of elapsed seconds from 1970-01-01T00:00:00Z. Instants on the time-line after the epoch are positive, earlier are negative.

        Parameters:
        offset - the offset to use for the conversion, not null
        Returns:
        the number of seconds from the epoch of 1970-01-01T00:00:00Z

      • compareTo

        public int compareTo​(ChronoLocalDateTime<?> other)
        Compares this date-time to another date-time, including the chronology.

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

        For example, the following is the comparator order:

        1. 2012-12-03T12:00 (ISO)
        2. 2012-12-04T12:00 (ISO)
        3. 2555-12-04T12:00 (ThaiBuddhist)
        4. 2012-12-05T12:00 (ISO)
        Values #2 and #3 represent the same date-time on the time-line. When two values represent the same date-time, the chronology ID is compared to distinguish them. This step is needed to make the ordering "consistent with equals".

        If all the date-time objects being compared are in the same chronology, then the additional chronology stage is not required and only the local date-time is used.

        Specified by:
        compareTo in interface Comparable<D extends ChronoLocalDate>
        Parameters:
        other - the other date-time to compare to, not null
        Returns:
        the comparator value, negative if less, positive if greater

      • isAfter

        public boolean isAfter​(ChronoLocalDateTime<?> other)
        Checks if this date-time is after the specified date-time ignoring the chronology.

        This method differs from the comparison in compareTo(org.threeten.bp.chrono.ChronoLocalDateTime<?>) in that it only compares the underlying date-time and not the chronology. This allows dates in different calendar systems to be compared based on the time-line position.

        Parameters:
        other - the other date-time to compare to, not null
        Returns:
        true if this is after the specified date-time

      • isBefore

        public boolean isBefore​(ChronoLocalDateTime<?> other)
        Checks if this date-time is before the specified date-time ignoring the chronology.

        This method differs from the comparison in compareTo(org.threeten.bp.chrono.ChronoLocalDateTime<?>) in that it only compares the underlying date-time and not the chronology. This allows dates in different calendar systems to be compared based on the time-line position.

        Parameters:
        other - the other date-time to compare to, not null
        Returns:
        true if this is before the specified date-time

      • isEqual

        public boolean isEqual​(ChronoLocalDateTime<?> other)
        Checks if this date-time is equal to the specified date-time ignoring the chronology.

        This method differs from the comparison in compareTo(org.threeten.bp.chrono.ChronoLocalDateTime<?>) in that it only compares the underlying date and time and not the chronology. This allows date-times in different calendar systems to be compared based on the time-line position.

        Parameters:
        other - the other date-time to compare to, not null
        Returns:
        true if the underlying date-time is equal to the specified date-time on the timeline

      • equals

        public boolean equals​(Object obj)
        Checks if this date-time is equal to another date-time, including the chronology.

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

        Overrides:
        equals in class Object
        Parameters:
        obj - the object to check, null returns false
        Returns:
        true if this is equal to the other date

      • hashCode

        public int hashCode()
        A hash code for this date-time.
        Overrides:
        hashCode in class Object
        Returns:
        a suitable hash code

      • toString

        public String toString()
        Outputs this date-time as a String.

        The output will include the full local date-time and the chronology ID.

        Overrides:
        toString in class Object
        Returns:
        a string representation of this date-time, not null