* Most applications should declare method signatures, fields and variables * as {@link LocalDateTime}, not this interface. *
* A {@code ChronoLocalDateTime} is the abstract representation of a local date-time * where the {@code Chronology chronology}, or calendar system, is pluggable. * The date-time is defined in terms of fields expressed by {@link TemporalField}, * where most common implementations are defined in {@link ChronoField}. * The chronology defines how the calendar system operates and the meaning of * the standard fields. * *
* Ensure that the discussion in {@code ChronoLocalDate} has been read and understood
* before using this interface.
*
* @implSpec
* 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.
*
* @param
* This comparator differs from the comparison in {@link #compareTo} 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 position of the date-time on the local time-line.
* The underlying comparison is equivalent to comparing the epoch-day and nano-of-day.
*
* @return a comparator that compares in time-line order ignoring the chronology
* @see #isAfter
* @see #isBefore
* @see #isEqual
*/
static Comparator
* This obtains a local date-time based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code ChronoLocalDateTime}.
*
* The conversion extracts and combines the chronology and the date-time
* from the temporal object. The behavior is equivalent to using
* {@link 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 {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code ChronoLocalDateTime::from}.
*
* @param temporal the temporal object to convert, not null
* @return the date-time, not null
* @throws DateTimeException if unable to convert to a {@code ChronoLocalDateTime}
* @see Chronology#localDateTime(TemporalAccessor)
*/
static ChronoLocalDateTime from(TemporalAccessor temporal) {
if (temporal instanceof ChronoLocalDateTime) {
return (ChronoLocalDateTime) temporal;
}
Objects.requireNonNull(temporal, "temporal");
Chronology chrono = temporal.query(TemporalQueries.chronology());
if (chrono == null) {
throw new DateTimeException("Unable to obtain ChronoLocalDateTime from TemporalAccessor: " + temporal.getClass());
}
return chrono.localDateTime(temporal);
}
//-----------------------------------------------------------------------
/**
* Gets the chronology of this date-time.
*
* The {@code Chronology} represents the calendar system in use.
* The era and other fields in {@link ChronoField} are defined by the chronology.
*
* @return the chronology, not null
*/
default Chronology getChronology() {
return toLocalDate().getChronology();
}
/**
* 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.
*
* @return the date part of this date-time, not null
*/
D toLocalDate() ;
/**
* 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.
*
* @return the time part of this date-time, not null
*/
LocalTime toLocalTime();
/**
* Checks if the specified field is supported.
*
* This checks if the specified field can be queried on this date-time.
* If false, then calling the {@link #range(TemporalField) range},
* {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
* methods will throw an exception.
*
* The set of supported fields is defined by the chronology and normally includes
* all {@code ChronoField} date and time fields.
*
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
* passing {@code this} as the argument.
* Whether the field is supported is determined by the field.
*
* @param field the field to check, null returns false
* @return true if the field can be queried, false if not
*/
@Override
boolean isSupported(TemporalField field);
/**
* 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 {@link #plus(long, TemporalUnit)} and
* {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
*
* The set of supported units is defined by the chronology and normally includes
* all {@code ChronoUnit} units except {@code FOREVER}.
*
* If the unit is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
* passing {@code this} as the argument.
* Whether the unit is supported is determined by the unit.
*
* @param unit the unit to check, null returns false
* @return true if the unit can be added/subtracted, false if not
*/
@Override
default boolean isSupported(TemporalUnit unit) {
if (unit instanceof ChronoUnit) {
return unit != FOREVER;
}
return unit != null && unit.isSupportedBy(this);
}
//-----------------------------------------------------------------------
// override for covariant return type
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
default ChronoLocalDateTime
* This queries this date-time using the specified query strategy object.
* The {@code 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
* {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
* specified query passing {@code this} as the argument.
*
* @param
* This returns a temporal object of the same observable type as the input
* with the date and time changed to be the same as this.
*
* The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
* twice, passing {@link ChronoField#EPOCH_DAY} and
* {@link ChronoField#NANO_OF_DAY} as the fields.
*
* In most cases, it is clearer to reverse the calling pattern by using
* {@link Temporal#with(TemporalAdjuster)}:
*
* This instance is immutable and unaffected by this method call.
*
* @param temporal the target object to be adjusted, not null
* @return the adjusted object, not null
* @throws DateTimeException if unable to make the adjustment
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
default Temporal adjustInto(Temporal temporal) {
return temporal
.with(EPOCH_DAY, toLocalDate().toEpochDay())
.with(NANO_OF_DAY, toLocalTime().toNanoOfDay());
}
/**
* 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:
*
* This returns a {@code 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 {@link ZoneRules 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
* {@link ChronoZonedDateTime#withLaterOffsetAtOverlap()} on the result of this method.
*
* @param zone the time-zone to use, not null
* @return the zoned date-time formed from this date-time, not null
*/
ChronoZonedDateTime
* This combines this local date-time and the specified offset to form
* an {@code Instant}.
*
* This default implementation calculates from the epoch-day of the date and the
* second-of-day of the time.
*
* @param offset the offset to use for the conversion, not null
* @return an {@code Instant} representing the same instant, not null
*/
default Instant toInstant(ZoneOffset offset) {
return Instant.ofEpochSecond(toEpochSecond(offset), toLocalTime().getNano());
}
/**
* 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.
*
* This default implementation calculates from the epoch-day of the date and the
* second-of-day of the time.
*
* @param offset the offset to use for the conversion, not null
* @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
*/
default long toEpochSecond(ZoneOffset offset) {
Objects.requireNonNull(offset, "offset");
long epochDay = toLocalDate().toEpochDay();
long secs = epochDay * 86400 + toLocalTime().toSecondOfDay();
secs -= offset.getTotalSeconds();
return secs;
}
//-----------------------------------------------------------------------
/**
* 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 {@link Comparable}.
*
* For example, the following is the comparator order:
*
* 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.
*
* This default implementation performs the comparison defined above.
*
* @param other the other date-time to compare to, not null
* @return the comparator value, negative if less, positive if greater
*/
@Override
default int compareTo(ChronoLocalDateTime other) {
int cmp = toLocalDate().compareTo(other.toLocalDate());
if (cmp == 0) {
cmp = toLocalTime().compareTo(other.toLocalTime());
if (cmp == 0) {
cmp = getChronology().compareTo(other.getChronology());
}
}
return cmp;
}
/**
* Checks if this date-time is after the specified date-time ignoring the chronology.
*
* This method differs from the comparison in {@link #compareTo} 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.
*
* This default implementation performs the comparison based on the epoch-day
* and nano-of-day.
*
* @param other the other date-time to compare to, not null
* @return true if this is after the specified date-time
*/
default boolean isAfter(ChronoLocalDateTime other) {
long thisEpDay = this.toLocalDate().toEpochDay();
long otherEpDay = other.toLocalDate().toEpochDay();
return thisEpDay > otherEpDay ||
(thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() > other.toLocalTime().toNanoOfDay());
}
/**
* Checks if this date-time is before the specified date-time ignoring the chronology.
*
* This method differs from the comparison in {@link #compareTo} 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.
*
* This default implementation performs the comparison based on the epoch-day
* and nano-of-day.
*
* @param other the other date-time to compare to, not null
* @return true if this is before the specified date-time
*/
default boolean isBefore(ChronoLocalDateTime other) {
long thisEpDay = this.toLocalDate().toEpochDay();
long otherEpDay = other.toLocalDate().toEpochDay();
return thisEpDay < otherEpDay ||
(thisEpDay == otherEpDay && this.toLocalTime().toNanoOfDay() < other.toLocalTime().toNanoOfDay());
}
/**
* Checks if this date-time is equal to the specified date-time ignoring the chronology.
*
* This method differs from the comparison in {@link #compareTo} 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.
*
* This default implementation performs the comparison based on the epoch-day
* and nano-of-day.
*
* @param other the other date-time to compare to, not null
* @return true if the underlying date-time is equal to the specified date-time on the timeline
*/
default boolean isEqual(ChronoLocalDateTime other) {
// Do the time check first, it is cheaper than computing EPOCH day.
return this.toLocalTime().toNanoOfDay() == other.toLocalTime().toNanoOfDay() &&
this.toLocalDate().toEpochDay() == other.toLocalDate().toEpochDay();
}
/**
* 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.
*
* @param obj the object to check, null returns false
* @return true if this is equal to the other date
*/
@Override
boolean equals(Object obj);
/**
* A hash code for this date-time.
*
* @return a suitable hash code
*/
@Override
int hashCode();
//-----------------------------------------------------------------------
/**
* Outputs this date-time as a {@code String}.
*
* The output will include the full local date-time.
*
* @return a string representation of this date-time, not null
*/
@Override
String toString();
}
* // these two lines are equivalent, but the second approach is recommended
* temporal = thisLocalDateTime.adjustInto(temporal);
* temporal = temporal.with(thisLocalDateTime);
*
*
* return formatter.format(this);
*
*
* @param formatter the formatter to use, not null
* @return the formatted date-time string, not null
* @throws DateTimeException if an error occurs during printing
*/
default String format(DateTimeFormatter formatter) {
Objects.requireNonNull(formatter, "formatter");
return formatter.format(this);
}
//-----------------------------------------------------------------------
/**
* Combines this time with a time-zone to create a {@code ChronoZonedDateTime}.
*
*
* 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".
*