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* However, the following notice accompanied the original version of this
* file:
*
* Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
*
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package java.time.chrono;
import static java.time.temporal.ChronoField.INSTANT_SECONDS;
import static java.time.temporal.ChronoField.OFFSET_SECONDS;
import static java.time.temporal.ChronoUnit.FOREVER;
import static java.time.temporal.ChronoUnit.NANOS;
import java.time.DateTimeException;
import java.time.Instant;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.ZoneOffset;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.time.temporal.ChronoField;
import java.time.temporal.ChronoUnit;
import java.time.temporal.Temporal;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalAdjuster;
import java.time.temporal.TemporalAmount;
import java.time.temporal.TemporalField;
import java.time.temporal.TemporalQueries;
import java.time.temporal.TemporalQuery;
import java.time.temporal.TemporalUnit;
import java.time.temporal.UnsupportedTemporalTypeException;
import java.time.temporal.ValueRange;
import java.util.Comparator;
import java.util.Objects;
/**
* A date-time with a time-zone in an arbitrary chronology,
* intended for advanced globalization use cases.
* <p>
* <b>Most applications should declare method signatures, fields and variables
* as {@link ZonedDateTime}, not this interface.</b>
* <p>
* A {@code ChronoZonedDateTime} is the abstract representation of an offset 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.
*
* <h3>When to use this interface</h3>
* The design of the API encourages the use of {@code ZonedDateTime} 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 {@link ChronoLocalDate}.
* <p>
* 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 <D> the concrete type for the date of this date-time
* @since 1.8
*/
public interface ChronoZonedDateTime<D extends ChronoLocalDate>
extends Temporal, Comparable<ChronoZonedDateTime<?>> {
/**
* Gets a comparator that compares {@code ChronoZonedDateTime} in
* time-line order ignoring the chronology.
* <p>
* This comparator differs from the comparison in {@link #compareTo} in that it
* only compares the underlying instant and not the chronology.
* This allows dates in different calendar systems to be compared based
* on the position of the date-time on the instant time-line.
* The underlying comparison is equivalent to comparing the epoch-second and nano-of-second.
*
* @return a comparator that compares in time-line order ignoring the chronology
*
* @see #isAfter
* @see #isBefore
* @see #isEqual
*/
static Comparator<ChronoZonedDateTime<?>> timeLineOrder() {
return AbstractChronology.INSTANT_ORDER;
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code ChronoZonedDateTime} from a temporal object.
* <p>
* This creates a zoned 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 ChronoZonedDateTime}.
* <p>
* The conversion extracts and combines the chronology, date, time and zone
* from the temporal object. The behavior is equivalent to using
* {@link Chronology#zonedDateTime(TemporalAccessor)} with the extracted chronology.
* Implementations are permitted to perform optimizations such as accessing
* those fields that are equivalent to the relevant objects.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code ChronoZonedDateTime::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 ChronoZonedDateTime}
* @see Chronology#zonedDateTime(TemporalAccessor)
*/
static ChronoZonedDateTime<?> from(TemporalAccessor temporal) {
if (temporal instanceof ChronoZonedDateTime) {
return (ChronoZonedDateTime<?>) temporal;
}
Objects.requireNonNull(temporal, "temporal");
Chronology chrono = temporal.query(TemporalQueries.chronology());
if (chrono == null) {
throw new DateTimeException("Unable to obtain ChronoZonedDateTime from TemporalAccessor: " + temporal.getClass());
}
return chrono.zonedDateTime(temporal);
}
//-----------------------------------------------------------------------
@Override
default ValueRange range(TemporalField field) {
if (field instanceof ChronoField) {
if (field == INSTANT_SECONDS || field == OFFSET_SECONDS) {
return field.range();
}
return toLocalDateTime().range(field);
}
return field.rangeRefinedBy(this);
}
@Override
default int get(TemporalField field) {
if (field instanceof ChronoField) {
switch ((ChronoField) field) {
case INSTANT_SECONDS:
throw new UnsupportedTemporalTypeException("Invalid field 'InstantSeconds' for get() method, use getLong() instead");
case OFFSET_SECONDS:
return getOffset().getTotalSeconds();
}
return toLocalDateTime().get(field);
}
return Temporal.super.get(field);
}
@Override
default long getLong(TemporalField field) {
if (field instanceof ChronoField) {
switch ((ChronoField) field) {
case INSTANT_SECONDS: return toEpochSecond();
case OFFSET_SECONDS: return getOffset().getTotalSeconds();
}
return toLocalDateTime().getLong(field);
}
return field.getFrom(this);
}
/**
* Gets the local date part of this date-time.
* <p>
* 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
*/
default D toLocalDate() {
return toLocalDateTime().toLocalDate();
}
/**
* Gets the local time part of this date-time.
* <p>
* 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
*/
default LocalTime toLocalTime() {
return toLocalDateTime().toLocalTime();
}
/**
* Gets the local date-time part of this date-time.
* <p>
* This returns a local date with the same year, month and day
* as this date-time.
*
* @return the local date-time part of this date-time, not null
*/
ChronoLocalDateTime<D> toLocalDateTime();
/**
* Gets the chronology of this date-time.
* <p>
* 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 zone offset, such as '+01:00'.
* <p>
* This is the offset of the local date-time from UTC/Greenwich.
*
* @return the zone offset, not null
*/
ZoneOffset getOffset();
/**
* Gets the zone ID, such as 'Europe/Paris'.
* <p>
* This returns the stored time-zone id used to determine the time-zone rules.
*
* @return the zone ID, not null
*/
ZoneId getZone();
//-----------------------------------------------------------------------
/**
* Returns a copy of this date-time changing the zone offset to the
* earlier of the two valid offsets at a local time-line overlap.
* <p>
* This method only has any effect when the local time-line overlaps, such as
* at an autumn daylight savings cutover. In this scenario, there are two
* valid offsets for the local date-time. Calling this method will return
* a zoned date-time with the earlier of the two selected.
* <p>
* If this method is called when it is not an overlap, {@code this}
* is returned.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @return a {@code ZoneChronoDateTime} based on this date-time with the earlier offset, not null
* @throws DateTimeException if no rules can be found for the zone
* @throws DateTimeException if no rules are valid for this date-time
*/
ChronoZonedDateTime<D> withEarlierOffsetAtOverlap();
/**
* Returns a copy of this date-time changing the zone offset to the
* later of the two valid offsets at a local time-line overlap.
* <p>
* This method only has any effect when the local time-line overlaps, such as
* at an autumn daylight savings cutover. In this scenario, there are two
* valid offsets for the local date-time. Calling this method will return
* a zoned date-time with the later of the two selected.
* <p>
* If this method is called when it is not an overlap, {@code this}
* is returned.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @return a {@code ChronoZonedDateTime} based on this date-time with the later offset, not null
* @throws DateTimeException if no rules can be found for the zone
* @throws DateTimeException if no rules are valid for this date-time
*/
ChronoZonedDateTime<D> withLaterOffsetAtOverlap();
/**
* Returns a copy of this ZonedDateTime with a different time-zone,
* retaining the local date-time if possible.
* <p>
* This method changes the time-zone and retains the local date-time.
* The local date-time is only changed if it is invalid for the new zone.
* <p>
* To change the zone and adjust the local date-time,
* use {@link #withZoneSameInstant(ZoneId)}.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param zone the time-zone to change to, not null
* @return a {@code ChronoZonedDateTime} based on this date-time with the requested zone, not null
*/
ChronoZonedDateTime<D> withZoneSameLocal(ZoneId zone);
/**
* Returns a copy of this date-time with a different time-zone,
* retaining the instant.
* <p>
* This method changes the time-zone and retains the instant.
* This normally results in a change to the local date-time.
* <p>
* This method is based on retaining the same instant, thus gaps and overlaps
* in the local time-line have no effect on the result.
* <p>
* To change the offset while keeping the local time,
* use {@link #withZoneSameLocal(ZoneId)}.
*
* @param zone the time-zone to change to, not null
* @return a {@code ChronoZonedDateTime} based on this date-time with the requested zone, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
ChronoZonedDateTime<D> withZoneSameInstant(ZoneId zone);
/**
* Checks if the specified field is supported.
* <p>
* 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.
* <p>
* The set of supported fields is defined by the chronology and normally includes
* all {@code ChronoField} fields.
* <p>
* 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.
* <p>
* 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.
* <p>
* The set of supported units is defined by the chronology and normally includes
* all {@code ChronoUnit} units except {@code FOREVER}.
* <p>
* 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 ChronoZonedDateTime<D> with(TemporalAdjuster adjuster) {
return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.with(adjuster));
}
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
ChronoZonedDateTime<D> with(TemporalField field, long newValue);
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
default ChronoZonedDateTime<D> plus(TemporalAmount amount) {
return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.plus(amount));
}
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
ChronoZonedDateTime<D> plus(long amountToAdd, TemporalUnit unit);
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
default ChronoZonedDateTime<D> minus(TemporalAmount amount) {
return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amount));
}
/**
* {@inheritDoc}
* @throws DateTimeException {@inheritDoc}
* @throws ArithmeticException {@inheritDoc}
*/
@Override
default ChronoZonedDateTime<D> minus(long amountToSubtract, TemporalUnit unit) {
return ChronoZonedDateTimeImpl.ensureValid(getChronology(), Temporal.super.minus(amountToSubtract, unit));
}
//-----------------------------------------------------------------------
/**
* Queries this date-time using the specified query.
* <p>
* 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.
* <p>
* The result of this method is obtained by invoking the
* {@link java.time.temporal.TemporalQuery#queryFrom(TemporalAccessor)} method on the
* specified query passing {@code this} as the argument.
*
* @param <R> the type of the result
* @param query the query to invoke, not null
* @return the query result, null may be returned (defined by the query)
* @throws DateTimeException if unable to query (defined by the query)
* @throws ArithmeticException if numeric overflow occurs (defined by the query)
*/
@SuppressWarnings("unchecked")
@Override
default <R> R query(TemporalQuery<R> query) {
if (query == TemporalQueries.zone() || query == TemporalQueries.zoneId()) {
return (R) getZone();
} else if (query == TemporalQueries.offset()) {
return (R) getOffset();
} else if (query == TemporalQueries.localTime()) {
return (R) toLocalTime();
} else if (query == TemporalQueries.chronology()) {
return (R) getChronology();
} else if (query == TemporalQueries.precision()) {
return (R) NANOS;
}
// inline TemporalAccessor.super.query(query) as an optimization
// non-JDK classes are not permitted to make this optimization
return query.queryFrom(this);
}
/**
* Formats this date-time using the specified formatter.
* <p>
* This date-time will be passed to the formatter to produce a string.
* <p>
* The default implementation must behave as follows:
* <pre>
* return formatter.format(this);
* </pre>
*
* @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);
}
//-----------------------------------------------------------------------
/**
* Converts this date-time to an {@code Instant}.
* <p>
* This returns an {@code Instant} representing the same point on the
* time-line as this date-time. The calculation combines the
* {@linkplain #toLocalDateTime() local date-time} and
* {@linkplain #getOffset() offset}.
*
* @return an {@code Instant} representing the same instant, not null
*/
default Instant toInstant() {
return Instant.ofEpochSecond(toEpochSecond(), toLocalTime().getNano());
}
/**
* Converts this date-time to the number of seconds from the epoch
* of 1970-01-01T00:00:00Z.
* <p>
* This uses the {@linkplain #toLocalDateTime() local date-time} and
* {@linkplain #getOffset() 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.
*
* @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
*/
default long toEpochSecond() {
long epochDay = toLocalDate().toEpochDay();
long secs = epochDay * 86400 + toLocalTime().toSecondOfDay();
secs -= getOffset().getTotalSeconds();
return secs;
}
//-----------------------------------------------------------------------
/**
* Compares this date-time to another date-time, including the chronology.
* <p>
* The comparison is based first on the instant, then on the local date-time,
* then on the zone ID, then on the chronology.
* It is "consistent with equals", as defined by {@link Comparable}.
* <p>
* If all the date-time objects being compared are in the same chronology, then the
* additional chronology stage is not required.
* <p>
* 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(ChronoZonedDateTime<?> other) {
int cmp = Long.compare(toEpochSecond(), other.toEpochSecond());
if (cmp == 0) {
cmp = toLocalTime().getNano() - other.toLocalTime().getNano();
if (cmp == 0) {
cmp = toLocalDateTime().compareTo(other.toLocalDateTime());
if (cmp == 0) {
cmp = getZone().getId().compareTo(other.getZone().getId());
if (cmp == 0) {
cmp = getChronology().compareTo(other.getChronology());
}
}
}
}
return cmp;
}
/**
* Checks if the instant of this date-time is before that of the specified date-time.
* <p>
* This method differs from the comparison in {@link #compareTo} in that it
* only compares the instant of the date-time. This is equivalent to using
* {@code dateTime1.toInstant().isBefore(dateTime2.toInstant());}.
* <p>
* This default implementation performs the comparison based on the epoch-second
* and nano-of-second.
*
* @param other the other date-time to compare to, not null
* @return true if this point is before the specified date-time
*/
default boolean isBefore(ChronoZonedDateTime<?> other) {
long thisEpochSec = toEpochSecond();
long otherEpochSec = other.toEpochSecond();
return thisEpochSec < otherEpochSec ||
(thisEpochSec == otherEpochSec && toLocalTime().getNano() < other.toLocalTime().getNano());
}
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