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	/*
	* Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* * Redistributions of source code must retain the above copyright notice,
	* this list of conditions and the following disclaimer.
	*
	* * Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
	* and/or other materials provided with the distribution.
	*
	* * Neither the name of JSR-310 nor the names of its contributors
	* may be used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/
	package java.time;

	import static java.time.temporal.ChronoField.INSTANT_SECONDS;
	import static java.time.temporal.ChronoField.NANO_OF_SECOND;
	import static java.time.temporal.ChronoField.OFFSET_SECONDS;

	import java.io.DataOutput;
	import java.io.IOException;
	import java.io.ObjectInput;
	import java.io.InvalidObjectException;
	import java.io.ObjectInputStream;
	import java.io.Serializable;
	import java.time.chrono.ChronoZonedDateTime;
	import java.time.format.DateTimeFormatter;
	import java.time.format.DateTimeParseException;
	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.time.zone.ZoneOffsetTransition;
	import java.time.zone.ZoneRules;
	import java.util.List;
	import java.util.Objects;

	/**
	* A date-time with a time-zone in the ISO-8601 calendar system,
	* such as {@code 2007-12-03T10:15:30+01:00 Europe/Paris}.
	* <p>
	* {@code ZonedDateTime} is an immutable representation of a date-time with a time-zone.
	* This class stores all date and time fields, to a precision of nanoseconds,
	* and a time-zone, with a zone offset used to handle ambiguous local date-times.
	* For example, the value
	* "2nd October 2007 at 13:45.30.123456789 +02:00 in the Europe/Paris time-zone"
	* can be stored in a {@code ZonedDateTime}.
	* <p>
	* This class handles conversion from the local time-line of {@code LocalDateTime}
	* to the instant time-line of {@code Instant}.
	* The difference between the two time-lines is the offset from UTC/Greenwich,
	* represented by a {@code ZoneOffset}.
	* <p>
	* Converting between the two time-lines involves calculating the offset using the
	* {@link ZoneRules rules} accessed from the {@code ZoneId}.
	* Obtaining the offset for an instant is simple, as there is exactly one valid
	* offset for each instant. By contrast, obtaining the offset for a local date-time
	* is not straightforward. There are three cases:
	* <ul>
	* <li>Normal, with one valid offset. For the vast majority of the year, the normal
	* case applies, where there is a single valid offset for the local date-time.</li>
	* <li>Gap, with zero valid offsets. This is when clocks jump forward typically
	* due to the spring daylight savings change from "winter" to "summer".
	* In a gap there are local date-time values with no valid offset.</li>
	* <li>Overlap, with two valid offsets. This is when clocks are set back typically
	* due to the autumn daylight savings change from "summer" to "winter".
	* In an overlap there are local date-time values with two valid offsets.</li>
	* </ul>
	* <p>
	* Any method that converts directly or implicitly from a local date-time to an
	* instant by obtaining the offset has the potential to be complicated.
	* <p>
	* For Gaps, the general strategy is that if the local date-time falls in the
	* middle of a Gap, then the resulting zoned date-time will have a local date-time
	* shifted forwards by the length of the Gap, resulting in a date-time in the later
	* offset, typically "summer" time.
	* <p>
	* For Overlaps, the general strategy is that if the local date-time falls in the
	* middle of an Overlap, then the previous offset will be retained. If there is no
	* previous offset, or the previous offset is invalid, then the earlier offset is
	* used, typically "summer" time.. Two additional methods,
	* {@link #withEarlierOffsetAtOverlap()} and {@link #withLaterOffsetAtOverlap()},
	* help manage the case of an overlap.
	* <p>
	* In terms of design, this class should be viewed primarily as the combination
	* of a {@code LocalDateTime} and a {@code ZoneId}. The {@code ZoneOffset} is
	* a vital, but secondary, piece of information, used to ensure that the class
	* represents an instant, especially during a daylight savings overlap.
	*
	* <p>
	* This is a <a href="{@docRoot}/java/lang/doc-files/ValueBased.html">value-based</a>
	* class; use of identity-sensitive operations (including reference equality
	* ({@code ==}), identity hash code, or synchronization) on instances of
	* {@code ZonedDateTime} may have unpredictable results and should be avoided.
	* The {@code equals} method should be used for comparisons.
	*
	* @implSpec
	* A {@code ZonedDateTime} holds state equivalent to three separate objects,
	* a {@code LocalDateTime}, a {@code ZoneId} and the resolved {@code ZoneOffset}.
	* The offset and local date-time are used to define an instant when necessary.
	* The zone ID is used to obtain the rules for how and when the offset changes.
	* The offset cannot be freely set, as the zone controls which offsets are valid.
	* <p>
	* This class is immutable and thread-safe.
	*
	* @since 1.8
	*/
	public final class ZonedDateTime
	implements Temporal, ChronoZonedDateTime<LocalDate>, Serializable {

	/**
	* Serialization version.
	*/
	private static final long serialVersionUID = -6260982410461394882L;

	/**
	* The local date-time.
	*/
	private final LocalDateTime dateTime;
	/**
	* The offset from UTC/Greenwich.
	*/
	private final ZoneOffset offset;
	/**
	* The time-zone.
	*/
	private final ZoneId zone;

	//-----------------------------------------------------------------------
	/**
	* Obtains the current date-time from the system clock in the default time-zone.
	* <p>
	* This will query the {@link Clock#systemDefaultZone() system clock} in the default
	* time-zone to obtain the current date-time.
	* The zone and offset will be set based on the time-zone in the clock.
	* <p>
	* Using this method will prevent the ability to use an alternate clock for testing
	* because the clock is hard-coded.
	*
	* @return the current date-time using the system clock, not null
	*/
	public static ZonedDateTime now() {
	return now(Clock.systemDefaultZone());
	}

	/**
	* Obtains the current date-time from the system clock in the specified time-zone.
	* <p>
	* This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date-time.
	* Specifying the time-zone avoids dependence on the default time-zone.
	* The offset will be calculated from the specified time-zone.
	* <p>
	* Using this method will prevent the ability to use an alternate clock for testing
	* because the clock is hard-coded.
	*
	* @param zone the zone ID to use, not null
	* @return the current date-time using the system clock, not null
	*/
	public static ZonedDateTime now(ZoneId zone) {
	return now(Clock.system(zone));
	}

	/**
	* Obtains the current date-time from the specified clock.
	* <p>
	* This will query the specified clock to obtain the current date-time.
	* The zone and offset will be set based on the time-zone in the clock.
	* <p>
	* Using this method allows the use of an alternate clock for testing.
	* The alternate clock may be introduced using {@link Clock dependency injection}.
	*
	* @param clock the clock to use, not null
	* @return the current date-time, not null
	*/
	public static ZonedDateTime now(Clock clock) {
	Objects.requireNonNull(clock, "clock");
	final Instant now = clock.instant(); // called once
	return ofInstant(now, clock.getZone());
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZonedDateTime} from a local date and time.
	* <p>
	* This creates a zoned date-time matching the input local date and 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.
	* <p>
	* The local date time and first combined to form a local date-time.
	* The local date-time is then 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.
	*<p>
	* In most cases, there is only one valid offset for a local date-time.
	* In the case of an overlap, when clocks are set back, there are two valid offsets.
	* This method uses the earlier offset typically corresponding to "summer".
	* <p>
	* In the case of a gap, when 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".
	*
	* @param date the local date, not null
	* @param time the local time, not null
	* @param zone the time-zone, not null
	* @return the offset date-time, not null
	*/
	public static ZonedDateTime of(LocalDate date, LocalTime time, ZoneId zone) {
	return of(LocalDateTime.of(date, time), zone);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} from a local date-time.
	* <p>
	* This creates a zoned date-time matching the input local 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.
	* <p>
	* 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.
	*<p>
	* In most cases, there is only one valid offset for a local date-time.
	* In the case of an overlap, when clocks are set back, there are two valid offsets.
	* This method uses the earlier offset typically corresponding to "summer".
	* <p>
	* In the case of a gap, when 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".
	*
	* @param localDateTime the local date-time, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	*/
	public static ZonedDateTime of(LocalDateTime localDateTime, ZoneId zone) {
	return ofLocal(localDateTime, zone, null);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} from a year, month, day,
	* hour, minute, second, nanosecond and time-zone.
	* <p>
	* This creates a zoned date-time matching the local date-time of the seven
	* specified fields 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.
	* <p>
	* 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.
	*<p>
	* In most cases, there is only one valid offset for a local date-time.
	* In the case of an overlap, when clocks are set back, there are two valid offsets.
	* This method uses the earlier offset typically corresponding to "summer".
	* <p>
	* In the case of a gap, when 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".
	* <p>
	* This method exists primarily for writing test cases.
	* Non test-code will typically use other methods to create an offset time.
	* {@code LocalDateTime} has five additional convenience variants of the
	* equivalent factory method taking fewer arguments.
	* They are not provided here to reduce the footprint of the API.
	*
	* @param year the year to represent, from MIN_YEAR to MAX_YEAR
	* @param month the month-of-year to represent, from 1 (January) to 12 (December)
	* @param dayOfMonth the day-of-month to represent, from 1 to 31
	* @param hour the hour-of-day to represent, from 0 to 23
	* @param minute the minute-of-hour to represent, from 0 to 59
	* @param second the second-of-minute to represent, from 0 to 59
	* @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
	* @param zone the time-zone, not null
	* @return the offset date-time, not null
	* @throws DateTimeException if the value of any field is out of range, or
	* if the day-of-month is invalid for the month-year
	*/
	public static ZonedDateTime of(
	int year, int month, int dayOfMonth,
	int hour, int minute, int second, int nanoOfSecond, ZoneId zone) {
	LocalDateTime dt = LocalDateTime.of(year, month, dayOfMonth, hour, minute, second, nanoOfSecond);
	return ofLocal(dt, zone, null);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} from a local date-time
	* using the preferred offset if possible.
	* <p>
	* 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.
	*<p>
	* 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.
	* If the preferred offset is one of the valid offsets then it is used.
	* Otherwise the earlier valid offset is used, typically corresponding to "summer".
	* <p>
	* 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".
	*
	* @param localDateTime the local date-time, not null
	* @param zone the time-zone, not null
	* @param preferredOffset the zone offset, null if no preference
	* @return the zoned date-time, not null
	*/
	public static ZonedDateTime ofLocal(LocalDateTime localDateTime, ZoneId zone, ZoneOffset preferredOffset) {
	Objects.requireNonNull(localDateTime, "localDateTime");
	Objects.requireNonNull(zone, "zone");
	if (zone instanceof ZoneOffset) {
	return new ZonedDateTime(localDateTime, (ZoneOffset) zone, zone);
	}
	ZoneRules rules = zone.getRules();
	List<ZoneOffset> validOffsets = rules.getValidOffsets(localDateTime);
	ZoneOffset offset;
	if (validOffsets.size() == 1) {
	offset = validOffsets.get(0);
	} else if (validOffsets.size() == 0) {
	ZoneOffsetTransition trans = rules.getTransition(localDateTime);
	localDateTime = localDateTime.plusSeconds(trans.getDuration().getSeconds());
	offset = trans.getOffsetAfter();
	} else {
	if (preferredOffset != null && validOffsets.contains(preferredOffset)) {
	offset = preferredOffset;
	} else {
	offset = Objects.requireNonNull(validOffsets.get(0), "offset"); // protect against bad ZoneRules
	}
	}
	return new ZonedDateTime(localDateTime, offset, zone);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZonedDateTime} from an {@code Instant}.
	* <p>
	* This creates a zoned date-time with the same instant as that specified.
	* Calling {@link #toInstant()} will return an instant equal to the one used here.
	* <p>
	* Converting an instant to a zoned date-time is simple as there is only one valid
	* offset for each instant.
	*
	* @param instant the instant to create the date-time from, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	* @throws DateTimeException if the result exceeds the supported range
	*/
	public static ZonedDateTime ofInstant(Instant instant, ZoneId zone) {
	Objects.requireNonNull(instant, "instant");
	Objects.requireNonNull(zone, "zone");
	return create(instant.getEpochSecond(), instant.getNano(), zone);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} from the instant formed by combining
	* the local date-time and offset.
	* <p>
	* This creates a zoned date-time by {@link LocalDateTime#toInstant(ZoneOffset) combining}
	* the {@code LocalDateTime} and {@code ZoneOffset}.
	* This combination uniquely specifies an instant without ambiguity.
	* <p>
	* Converting an instant to a zoned date-time is simple as there is only one valid
	* offset for each instant. If the valid offset is different to the offset specified,
	* then the date-time and offset of the zoned date-time will differ from those specified.
	* <p>
	* If the {@code ZoneId} to be used is a {@code ZoneOffset}, this method is equivalent
	* to {@link #of(LocalDateTime, ZoneId)}.
	*
	* @param localDateTime the local date-time, not null
	* @param offset the zone offset, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	*/
	public static ZonedDateTime ofInstant(LocalDateTime localDateTime, ZoneOffset offset, ZoneId zone) {
	Objects.requireNonNull(localDateTime, "localDateTime");
	Objects.requireNonNull(offset, "offset");
	Objects.requireNonNull(zone, "zone");
	if (zone.getRules().isValidOffset(localDateTime, offset)) {
	return new ZonedDateTime(localDateTime, offset, zone);
	}
	return create(localDateTime.toEpochSecond(offset), localDateTime.getNano(), zone);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} using seconds from the
	* epoch of 1970-01-01T00:00:00Z.
	*
	* @param epochSecond the number of seconds from the epoch of 1970-01-01T00:00:00Z
	* @param nanoOfSecond the nanosecond within the second, from 0 to 999,999,999
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	* @throws DateTimeException if the result exceeds the supported range
	*/
	private static ZonedDateTime create(long epochSecond, int nanoOfSecond, ZoneId zone) {
	ZoneRules rules = zone.getRules();
	Instant instant = Instant.ofEpochSecond(epochSecond, nanoOfSecond); // TODO: rules should be queryable by epochSeconds
	ZoneOffset offset = rules.getOffset(instant);
	LocalDateTime ldt = LocalDateTime.ofEpochSecond(epochSecond, nanoOfSecond, offset);
	return new ZonedDateTime(ldt, offset, zone);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZonedDateTime} strictly validating the
	* combination of local date-time, offset and zone ID.
	* <p>
	* This creates a zoned date-time ensuring that the offset is valid for the
	* local date-time according to the rules of the specified zone.
	* If the offset is invalid, an exception is thrown.
	*
	* @param localDateTime the local date-time, not null
	* @param offset the zone offset, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	*/
	public static ZonedDateTime ofStrict(LocalDateTime localDateTime, ZoneOffset offset, ZoneId zone) {
	Objects.requireNonNull(localDateTime, "localDateTime");
	Objects.requireNonNull(offset, "offset");
	Objects.requireNonNull(zone, "zone");
	ZoneRules rules = zone.getRules();
	if (rules.isValidOffset(localDateTime, offset) == false) {
	ZoneOffsetTransition trans = rules.getTransition(localDateTime);
	if (trans != null && trans.isGap()) {
	// error message says daylight savings for simplicity
	// even though there are other kinds of gaps
	throw new DateTimeException("LocalDateTime '" + localDateTime +
	"' does not exist in zone '" + zone +
	"' due to a gap in the local time-line, typically caused by daylight savings");
	}
	throw new DateTimeException("ZoneOffset '" + offset + "' is not valid for LocalDateTime '" +
	localDateTime + "' in zone '" + zone + "'");
	}
	return new ZonedDateTime(localDateTime, offset, zone);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} leniently, for advanced use cases,
	* allowing any combination of local date-time, offset and zone ID.
	* <p>
	* This creates a zoned date-time with no checks other than no nulls.
	* This means that the resulting zoned date-time may have an offset that is in conflict
	* with the zone ID.
	* <p>
	* This method is intended for advanced use cases.
	* For example, consider the case where a zoned date-time with valid fields is created
	* and then stored in a database or serialization-based store. At some later point,
	* the object is then re-loaded. However, between those points in time, the government
	* that defined the time-zone has changed the rules, such that the originally stored
	* local date-time now does not occur. This method can be used to create the object
	* in an "invalid" state, despite the change in rules.
	*
	* @param localDateTime the local date-time, not null
	* @param offset the zone offset, not null
	* @param zone the time-zone, not null
	* @return the zoned date-time, not null
	*/
	private static ZonedDateTime ofLenient(LocalDateTime localDateTime, ZoneOffset offset, ZoneId zone) {
	Objects.requireNonNull(localDateTime, "localDateTime");
	Objects.requireNonNull(offset, "offset");
	Objects.requireNonNull(zone, "zone");
	if (zone instanceof ZoneOffset && offset.equals(zone) == false) {
	throw new IllegalArgumentException("ZoneId must match ZoneOffset");
	}
	return new ZonedDateTime(localDateTime, offset, zone);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZonedDateTime} from a temporal object.
	* <p>
	* This obtains 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 ZonedDateTime}.
	* <p>
	* The conversion will first obtain a {@code ZoneId} from the temporal object,
	* falling back to a {@code ZoneOffset} if necessary. It will then try to obtain
	* an {@code Instant}, falling back to a {@code LocalDateTime} if necessary.
	* The result will be either the combination of {@code ZoneId} or {@code ZoneOffset}
	* with {@code Instant} or {@code LocalDateTime}.
	* 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 ZonedDateTime::from}.
	*
	* @param temporal the temporal object to convert, not null
	* @return the zoned date-time, not null
	* @throws DateTimeException if unable to convert to an {@code ZonedDateTime}
	*/
	public static ZonedDateTime from(TemporalAccessor temporal) {
	if (temporal instanceof ZonedDateTime) {
	return (ZonedDateTime) temporal;
	}
	try {
	ZoneId zone = ZoneId.from(temporal);
	if (temporal.isSupported(INSTANT_SECONDS)) {
	long epochSecond = temporal.getLong(INSTANT_SECONDS);
	int nanoOfSecond = temporal.get(NANO_OF_SECOND);
	return create(epochSecond, nanoOfSecond, zone);
	} else {
	LocalDate date = LocalDate.from(temporal);
	LocalTime time = LocalTime.from(temporal);
	return of(date, time, zone);
	}
	} catch (DateTimeException ex) {
	throw new DateTimeException("Unable to obtain ZonedDateTime from TemporalAccessor: " +
	temporal + " of type " + temporal.getClass().getName(), ex);
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZonedDateTime} from a text string such as
	* {@code 2007-12-03T10:15:30+01:00[Europe/Paris]}.
	* <p>
	* The string must represent a valid date-time and is parsed using
	* {@link java.time.format.DateTimeFormatter#ISO_ZONED_DATE_TIME}.
	*
	* @param text the text to parse such as "2007-12-03T10:15:30+01:00[Europe/Paris]", not null
	* @return the parsed zoned date-time, not null
	* @throws DateTimeParseException if the text cannot be parsed
	*/
	public static ZonedDateTime parse(CharSequence text) {
	return parse(text, DateTimeFormatter.ISO_ZONED_DATE_TIME);
	}

	/**
	* Obtains an instance of {@code ZonedDateTime} from a text string using a specific formatter.
	* <p>
	* The text is parsed using the formatter, returning a date-time.
	*
	* @param text the text to parse, not null
	* @param formatter the formatter to use, not null
	* @return the parsed zoned date-time, not null
	* @throws DateTimeParseException if the text cannot be parsed
	*/
	public static ZonedDateTime parse(CharSequence text, DateTimeFormatter formatter) {
	Objects.requireNonNull(formatter, "formatter");
	return formatter.parse(text, ZonedDateTime::from);
	}

	//-----------------------------------------------------------------------
	/**
	* Constructor.
	*
	* @param dateTime the date-time, validated as not null
	* @param offset the zone offset, validated as not null
	* @param zone the time-zone, validated as not null
	*/
	private ZonedDateTime(LocalDateTime dateTime, ZoneOffset offset, ZoneId zone) {
	this.dateTime = dateTime;
	this.offset = offset;
	this.zone = zone;
	}

	/**
	* Resolves the new local date-time using this zone ID, retaining the offset if possible.
	*
	* @param newDateTime the new local date-time, not null
	* @return the zoned date-time, not null
	*/
	private ZonedDateTime resolveLocal(LocalDateTime newDateTime) {
	return ofLocal(newDateTime, zone, offset);
	}

	/**
	* Resolves the new local date-time using the offset to identify the instant.
	*
	* @param newDateTime the new local date-time, not null
	* @return the zoned date-time, not null
	*/
	private ZonedDateTime resolveInstant(LocalDateTime newDateTime) {
	return ofInstant(newDateTime, offset, zone);
	}

	/**
	* Resolves the offset into this zoned date-time for the with methods.
	* <p>
	* This typically ignores the offset, unless it can be used to switch offset in a DST overlap.
	*
	* @param offset the offset, not null
	* @return the zoned date-time, not null
	*/
	private ZonedDateTime resolveOffset(ZoneOffset offset) {
	if (offset.equals(this.offset) == false && zone.getRules().isValidOffset(dateTime, offset)) {
	return new ZonedDateTime(dateTime, offset, zone);
	}
	return this;
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if the specified field is supported.
	* <p>
	* This checks if this date-time can be queried for the specified field.
	* If false, then calling the {@link #range(TemporalField) range},
	* {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
	* methods will throw an exception.
	* <p>
	* If the field is a {@link ChronoField} then the query is implemented here.
	* The supported fields are:
	* <ul>
	* <li>{@code NANO_OF_SECOND}
	* <li>{@code NANO_OF_DAY}
	* <li>{@code MICRO_OF_SECOND}
	* <li>{@code MICRO_OF_DAY}
	* <li>{@code MILLI_OF_SECOND}
	* <li>{@code MILLI_OF_DAY}
	* <li>{@code SECOND_OF_MINUTE}
	* <li>{@code SECOND_OF_DAY}
	* <li>{@code MINUTE_OF_HOUR}
	* <li>{@code MINUTE_OF_DAY}
	* <li>{@code HOUR_OF_AMPM}
	* <li>{@code CLOCK_HOUR_OF_AMPM}
	* <li>{@code HOUR_OF_DAY}
	* <li>{@code CLOCK_HOUR_OF_DAY}
	* <li>{@code AMPM_OF_DAY}
	* <li>{@code DAY_OF_WEEK}
	* <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
	* <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
	* <li>{@code DAY_OF_MONTH}
	* <li>{@code DAY_OF_YEAR}
	* <li>{@code EPOCH_DAY}
	* <li>{@code ALIGNED_WEEK_OF_MONTH}
	* <li>{@code ALIGNED_WEEK_OF_YEAR}
	* <li>{@code MONTH_OF_YEAR}
	* <li>{@code PROLEPTIC_MONTH}
	* <li>{@code YEAR_OF_ERA}
	* <li>{@code YEAR}
	* <li>{@code ERA}
	* <li>{@code INSTANT_SECONDS}
	* <li>{@code OFFSET_SECONDS}
	* </ul>
	* All other {@code ChronoField} instances will return false.
	* <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 is supported on this date-time, false if not
	*/
	@Override
	public boolean isSupported(TemporalField field) {
	return field instanceof ChronoField \|\| (field != null && field.isSupportedBy(this));
	}

	/**
	* 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>
	* If the unit is a {@link ChronoUnit} then the query is implemented here.
	* The supported units are:
	* <ul>
	* <li>{@code NANOS}
	* <li>{@code MICROS}
	* <li>{@code MILLIS}
	* <li>{@code SECONDS}
	* <li>{@code MINUTES}
	* <li>{@code HOURS}
	* <li>{@code HALF_DAYS}
	* <li>{@code DAYS}
	* <li>{@code WEEKS}
	* <li>{@code MONTHS}
	* <li>{@code YEARS}
	* <li>{@code DECADES}
	* <li>{@code CENTURIES}
	* <li>{@code MILLENNIA}
	* <li>{@code ERAS}
	* </ul>
	* All other {@code ChronoUnit} instances will return false.
	* <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 // override for Javadoc
	public boolean isSupported(TemporalUnit unit) {
	return ChronoZonedDateTime.super.isSupported(unit);
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the range of valid values for the specified field.
	* <p>
	* The range object expresses the minimum and maximum valid values for a field.
	* This date-time 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.
	* <p>
	* If the field is a {@link ChronoField} then the query is implemented here.
	* The {@link #isSupported(TemporalField) supported fields} will return
	* appropriate range instances.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
	* passing {@code this} as the argument.
	* Whether the range can be obtained is determined by the field.
	*
	* @param field the field to query the range for, not null
	* @return the range of valid values for the field, not null
	* @throws DateTimeException if the range for the field cannot be obtained
	* @throws UnsupportedTemporalTypeException if the field is not supported
	*/
	@Override
	public ValueRange range(TemporalField field) {
	if (field instanceof ChronoField) {
	if (field == INSTANT_SECONDS \|\| field == OFFSET_SECONDS) {
	return field.range();
	}
	return dateTime.range(field);
	}
	return field.rangeRefinedBy(this);
	}

	/**
	* Gets the value of the specified field from this date-time as an {@code int}.
	* <p>
	* This queries this date-time for the value of 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.
	* <p>
	* If the field is a {@link ChronoField} then the query is implemented here.
	* The {@link #isSupported(TemporalField) supported fields} will return valid
	* values based on this date-time, except {@code NANO_OF_DAY}, {@code MICRO_OF_DAY},
	* {@code EPOCH_DAY}, {@code PROLEPTIC_MONTH} and {@code INSTANT_SECONDS} which are too
	* large to fit in an {@code int} and throw a {@code DateTimeException}.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
	* passing {@code this} as the argument. Whether the value can be obtained,
	* and what the value represents, is determined by the field.
	*
	* @param field the field to get, not null
	* @return the value for the field
	* @throws DateTimeException if a value for the field cannot be obtained or
	* the value is outside the range of valid values for the field
	* @throws UnsupportedTemporalTypeException if the field is not supported or
	* the range of values exceeds an {@code int}
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override // override for Javadoc and performance
	public 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 dateTime.get(field);
	}
	return ChronoZonedDateTime.super.get(field);
	}

	/**
	* Gets the value of the specified field from this date-time as a {@code long}.
	* <p>
	* This queries this date-time for the value of 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.
	* <p>
	* If the field is a {@link ChronoField} then the query is implemented here.
	* The {@link #isSupported(TemporalField) supported fields} will return valid
	* values based on this date-time.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
	* passing {@code this} as the argument. Whether the value can be obtained,
	* and what the value represents, is determined by the field.
	*
	* @param field the field to get, not null
	* @return the value for the field
	* @throws DateTimeException if a value for the field cannot be obtained
	* @throws UnsupportedTemporalTypeException if the field is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public long getLong(TemporalField field) {
	if (field instanceof ChronoField) {
	switch ((ChronoField) field) {
	case INSTANT_SECONDS: return toEpochSecond();
	case OFFSET_SECONDS: return getOffset().getTotalSeconds();
	}
	return dateTime.getLong(field);
	}
	return field.getFrom(this);
	}

	//-----------------------------------------------------------------------
	/**
	* 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
	*/
	@Override
	public ZoneOffset getOffset() {
	return offset;
	}

	/**
	* 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 ZonedDateTime} based on this date-time with the earlier offset, not null
	*/
	@Override
	public ZonedDateTime withEarlierOffsetAtOverlap() {
	ZoneOffsetTransition trans = getZone().getRules().getTransition(dateTime);
	if (trans != null && trans.isOverlap()) {
	ZoneOffset earlierOffset = trans.getOffsetBefore();
	if (earlierOffset.equals(offset) == false) {
	return new ZonedDateTime(dateTime, earlierOffset, zone);
	}
	}
	return this;
	}

	/**
	* 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 ZonedDateTime} based on this date-time with the later offset, not null
	*/
	@Override
	public ZonedDateTime withLaterOffsetAtOverlap() {
	ZoneOffsetTransition trans = getZone().getRules().getTransition(toLocalDateTime());
	if (trans != null) {
	ZoneOffset laterOffset = trans.getOffsetAfter();
	if (laterOffset.equals(offset) == false) {
	return new ZonedDateTime(dateTime, laterOffset, zone);
	}
	}
	return this;
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the time-zone, such as 'Europe/Paris'.
	* <p>
	* This returns the zone ID. This identifies the time-zone {@link ZoneRules rules}
	* that determine when and how the offset from UTC/Greenwich changes.
	* <p>
	* The zone ID may be same as the {@linkplain #getOffset() offset}.
	* If this is true, then any future calculations, such as addition or subtraction,
	* have no complex edge cases due to time-zone rules.
	* See also {@link #withFixedOffsetZone()}.
	*
	* @return the time-zone, not null
	*/
	@Override
	public ZoneId getZone() {
	return zone;
	}

	/**
	* Returns a copy of this date-time 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,
	* determined using the same approach as
	* {@link #ofLocal(LocalDateTime, ZoneId, ZoneOffset)}.
	* <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 ZonedDateTime} based on this date-time with the requested zone, not null
	*/
	@Override
	public ZonedDateTime withZoneSameLocal(ZoneId zone) {
	Objects.requireNonNull(zone, "zone");
	return this.zone.equals(zone) ? this : ofLocal(dateTime, zone, offset);
	}

	/**
	* 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 ZonedDateTime} based on this date-time with the requested zone, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	@Override
	public ZonedDateTime withZoneSameInstant(ZoneId zone) {
	Objects.requireNonNull(zone, "zone");
	return this.zone.equals(zone) ? this :
	create(dateTime.toEpochSecond(offset), dateTime.getNano(), zone);
	}

	/**
	* Returns a copy of this date-time with the zone ID set to the offset.
	* <p>
	* This returns a zoned date-time where the zone ID is the same as {@link #getOffset()}.
	* The local date-time, offset and instant of the result will be the same as in this date-time.
	* <p>
	* Setting the date-time to a fixed single offset means that any future
	* calculations, such as addition or subtraction, have no complex edge cases
	* due to time-zone rules.
	* This might also be useful when sending a zoned date-time across a network,
	* as most protocols, such as ISO-8601, only handle offsets,
	* and not region-based zone IDs.
	* <p>
	* This is equivalent to {@code ZonedDateTime.of(zdt.toLocalDateTime(), zdt.getOffset())}.
	*
	* @return a {@code ZonedDateTime} with the zone ID set to the offset, not null
	*/
	public ZonedDateTime withFixedOffsetZone() {
	return this.zone.equals(offset) ? this : new ZonedDateTime(dateTime, offset, offset);
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the {@code LocalDateTime} part of this date-time.
	* <p>
	* This returns a {@code LocalDateTime} with the same year, month, day and time
	* as this date-time.
	*
	* @return the local date-time part of this date-time, not null
	*/
	@Override // override for return type
	public LocalDateTime toLocalDateTime() {
	return dateTime;
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the {@code LocalDate} part of this date-time.
	* <p>
	* This returns a {@code LocalDate} with the same year, month and day
	* as this date-time.
	*
	* @return the date part of this date-time, not null
	*/
	@Override // override for return type
	public LocalDate toLocalDate() {
	return dateTime.toLocalDate();
	}

	/**
	* Gets the year field.
	* <p>
	* This method returns the primitive {@code int} value for the year.
	* <p>
	* The year returned by this method is proleptic as per {@code get(YEAR)}.
	* To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
	*
	* @return the year, from MIN_YEAR to MAX_YEAR
	*/
	public int getYear() {
	return dateTime.getYear();
	}

	/**
	* Gets the month-of-year field from 1 to 12.
	* <p>
	* This method returns the month as an {@code int} from 1 to 12.
	* Application code is frequently clearer if the enum {@link Month}
	* is used by calling {@link #getMonth()}.
	*
	* @return the month-of-year, from 1 to 12
	* @see #getMonth()
	*/
	public int getMonthValue() {
	return dateTime.getMonthValue();
	}

	/**
	* Gets the month-of-year field using the {@code Month} enum.
	* <p>
	* This method returns the enum {@link Month} for the month.
	* This avoids confusion as to what {@code int} values mean.
	* If you need access to the primitive {@code int} value then the enum
	* provides the {@link Month#getValue() int value}.
	*
	* @return the month-of-year, not null
	* @see #getMonthValue()
	*/
	public Month getMonth() {
	return dateTime.getMonth();
	}

	/**
	* Gets the day-of-month field.
	* <p>
	* This method returns the primitive {@code int} value for the day-of-month.
	*
	* @return the day-of-month, from 1 to 31
	*/
	public int getDayOfMonth() {
	return dateTime.getDayOfMonth();
	}

	/**
	* Gets the day-of-year field.
	* <p>
	* This method returns the primitive {@code int} value for the day-of-year.
	*
	* @return the day-of-year, from 1 to 365, or 366 in a leap year
	*/
	public int getDayOfYear() {
	return dateTime.getDayOfYear();
	}

	/**
	* Gets the day-of-week field, which is an enum {@code DayOfWeek}.
	* <p>
	* This method returns the enum {@link DayOfWeek} for the day-of-week.
	* This avoids confusion as to what {@code int} values mean.
	* If you need access to the primitive {@code int} value then the enum
	* provides the {@link DayOfWeek#getValue() int value}.
	* <p>
	* Additional information can be obtained from the {@code DayOfWeek}.
	* This includes textual names of the values.
	*
	* @return the day-of-week, not null
	*/
	public DayOfWeek getDayOfWeek() {
	return dateTime.getDayOfWeek();
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the {@code LocalTime} part of this date-time.
	* <p>
	* This returns a {@code LocalTime} with the same hour, minute, second and
	* nanosecond as this date-time.
	*
	* @return the time part of this date-time, not null
	*/
	@Override // override for Javadoc and performance
	public LocalTime toLocalTime() {
	return dateTime.toLocalTime();
	}

	/**
	* Gets the hour-of-day field.
	*
	* @return the hour-of-day, from 0 to 23
	*/
	public int getHour() {
	return dateTime.getHour();
	}

	/**
	* Gets the minute-of-hour field.
	*
	* @return the minute-of-hour, from 0 to 59
	*/
	public int getMinute() {
	return dateTime.getMinute();
	}

	/**
	* Gets the second-of-minute field.
	*
	* @return the second-of-minute, from 0 to 59
	*/
	public int getSecond() {
	return dateTime.getSecond();
	}

	/**
	* Gets the nano-of-second field.
	*
	* @return the nano-of-second, from 0 to 999,999,999
	*/
	public int getNano() {
	return dateTime.getNano();
	}

	//-----------------------------------------------------------------------
	/**
	* Returns an adjusted copy of this date-time.
	* <p>
	* This returns a {@code ZonedDateTime}, based on this one, with the date-time adjusted.
	* The adjustment takes place using the specified adjuster strategy object.
	* Read the documentation of the adjuster to understand what adjustment will be made.
	* <p>
	* 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
	* {@link java.time.temporal.TemporalAdjusters TemporalAdjusters}.
	* These include finding the "last day of the month" and "next Wednesday".
	* Key date-time classes also implement the {@code TemporalAdjuster} interface,
	* such as {@link Month} and {@link java.time.MonthDay MonthDay}.
	* The adjuster is responsible for handling special cases, such as the varying
	* lengths of month and leap years.
	* <p>
	* For example this code returns a date on the last day of July:
	* <pre>
	* import static java.time.Month.*;
	* import static java.time.temporal.TemporalAdjusters.*;
	*
	* result = zonedDateTime.with(JULY).with(lastDayOfMonth());
	* </pre>
	* <p>
	* The classes {@link LocalDate} and {@link LocalTime} implement {@code TemporalAdjuster},
	* thus this method can be used to change the date, time or offset:
	* <pre>
	* result = zonedDateTime.with(date);
	* result = zonedDateTime.with(time);
	* </pre>
	* <p>
	* {@link ZoneOffset} also implements {@code TemporalAdjuster} however using it
	* as an argument typically has no effect. The offset of a {@code ZonedDateTime} is
	* controlled primarily by the time-zone. As such, changing the offset does not generally
	* make sense, because there is only one valid offset for the local date-time and zone.
	* If the zoned date-time is in a daylight savings overlap, then the offset is used
	* to switch between the two valid offsets. In all other cases, the offset is ignored.
	* <p>
	* The result of this method is obtained by invoking the
	* {@link TemporalAdjuster#adjustInto(Temporal)} method on the
	* specified adjuster passing {@code this} as the argument.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param adjuster the adjuster to use, not null
	* @return a {@code ZonedDateTime} based on {@code this} with the adjustment made, not null
	* @throws DateTimeException if the adjustment cannot be made
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime with(TemporalAdjuster adjuster) {
	// optimizations
	if (adjuster instanceof LocalDate) {
	return resolveLocal(LocalDateTime.of((LocalDate) adjuster, dateTime.toLocalTime()));
	} else if (adjuster instanceof LocalTime) {
	return resolveLocal(LocalDateTime.of(dateTime.toLocalDate(), (LocalTime) adjuster));
	} else if (adjuster instanceof LocalDateTime) {
	return resolveLocal((LocalDateTime) adjuster);
	} else if (adjuster instanceof OffsetDateTime) {
	OffsetDateTime odt = (OffsetDateTime) adjuster;
	return ofLocal(odt.toLocalDateTime(), zone, odt.getOffset());
	} else if (adjuster instanceof Instant) {
	Instant instant = (Instant) adjuster;
	return create(instant.getEpochSecond(), instant.getNano(), zone);
	} else if (adjuster instanceof ZoneOffset) {
	return resolveOffset((ZoneOffset) adjuster);
	}
	return (ZonedDateTime) adjuster.adjustInto(this);
	}

	/**
	* Returns a copy of this date-time with the specified field set to a new value.
	* <p>
	* This returns a {@code ZonedDateTime}, 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, month or day-of-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.
	* <p>
	* In some cases, changing the specified field can cause the resulting date-time to become invalid,
	* such as changing the month from 31st January to February would make the day-of-month invalid.
	* In cases like this, the field is responsible for resolving the date. Typically it will choose
	* the previous valid date, which would be the last valid day of February in this example.
	* <p>
	* If the field is a {@link ChronoField} then the adjustment is implemented here.
	* <p>
	* The {@code INSTANT_SECONDS} field will return a date-time with the specified instant.
	* The zone and nano-of-second are unchanged.
	* The result will have an offset derived from the new instant and original zone.
	* If the new instant value is outside the valid range then a {@code DateTimeException} will be thrown.
	* <p>
	* The {@code OFFSET_SECONDS} field will typically be ignored.
	* The offset of a {@code ZonedDateTime} is controlled primarily by the time-zone.
	* As such, changing the offset does not generally make sense, because there is only
	* one valid offset for the local date-time and zone.
	* If the zoned date-time is in a daylight savings overlap, then the offset is used
	* to switch between the two valid offsets. In all other cases, the offset is ignored.
	* If the new offset value is outside the valid range then a {@code DateTimeException} will be thrown.
	* <p>
	* The other {@link #isSupported(TemporalField) supported fields} will behave as per
	* the matching method on {@link LocalDateTime#with(TemporalField, long) LocalDateTime}.
	* The zone is not part of the calculation and will be unchanged.
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
	* passing {@code this} as the argument. In this case, the field determines
	* whether and how to adjust the instant.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param field the field to set in the result, not null
	* @param newValue the new value of the field in the result
	* @return a {@code ZonedDateTime} based on {@code this} with the specified field set, not null
	* @throws DateTimeException if the field cannot be set
	* @throws UnsupportedTemporalTypeException if the field is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime with(TemporalField field, long newValue) {
	if (field instanceof ChronoField) {
	ChronoField f = (ChronoField) field;
	switch (f) {
	case INSTANT_SECONDS:
	return create(newValue, getNano(), zone);
	case OFFSET_SECONDS:
	ZoneOffset offset = ZoneOffset.ofTotalSeconds(f.checkValidIntValue(newValue));
	return resolveOffset(offset);
	}
	return resolveLocal(dateTime.with(field, newValue));
	}
	return field.adjustInto(this, newValue);
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the year altered.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#withYear(int) changing the year} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param year the year to set in the result, from MIN_YEAR to MAX_YEAR
	* @return a {@code ZonedDateTime} based on this date-time with the requested year, not null
	* @throws DateTimeException if the year value is invalid
	*/
	public ZonedDateTime withYear(int year) {
	return resolveLocal(dateTime.withYear(year));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the month-of-year altered.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#withMonth(int) changing the month} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param month the month-of-year to set in the result, from 1 (January) to 12 (December)
	* @return a {@code ZonedDateTime} based on this date-time with the requested month, not null
	* @throws DateTimeException if the month-of-year value is invalid
	*/
	public ZonedDateTime withMonth(int month) {
	return resolveLocal(dateTime.withMonth(month));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the day-of-month altered.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#withDayOfMonth(int) changing the day-of-month} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param dayOfMonth the day-of-month to set in the result, from 1 to 28-31
	* @return a {@code ZonedDateTime} based on this date-time with the requested day, not null
	* @throws DateTimeException if the day-of-month value is invalid,
	* or if the day-of-month is invalid for the month-year
	*/
	public ZonedDateTime withDayOfMonth(int dayOfMonth) {
	return resolveLocal(dateTime.withDayOfMonth(dayOfMonth));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the day-of-year altered.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#withDayOfYear(int) changing the day-of-year} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param dayOfYear the day-of-year to set in the result, from 1 to 365-366
	* @return a {@code ZonedDateTime} based on this date with the requested day, not null
	* @throws DateTimeException if the day-of-year value is invalid,
	* or if the day-of-year is invalid for the year
	*/
	public ZonedDateTime withDayOfYear(int dayOfYear) {
	return resolveLocal(dateTime.withDayOfYear(dayOfYear));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the hour-of-day altered.
	* <p>
	* This operates on the local time-line,
	* {@linkplain LocalDateTime#withHour(int) changing the time} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param hour the hour-of-day to set in the result, from 0 to 23
	* @return a {@code ZonedDateTime} based on this date-time with the requested hour, not null
	* @throws DateTimeException if the hour value is invalid
	*/
	public ZonedDateTime withHour(int hour) {
	return resolveLocal(dateTime.withHour(hour));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the minute-of-hour altered.
	* <p>
	* This operates on the local time-line,
	* {@linkplain LocalDateTime#withMinute(int) changing the time} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param minute the minute-of-hour to set in the result, from 0 to 59
	* @return a {@code ZonedDateTime} based on this date-time with the requested minute, not null
	* @throws DateTimeException if the minute value is invalid
	*/
	public ZonedDateTime withMinute(int minute) {
	return resolveLocal(dateTime.withMinute(minute));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the second-of-minute altered.
	* <p>
	* This operates on the local time-line,
	* {@linkplain LocalDateTime#withSecond(int) changing the time} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param second the second-of-minute to set in the result, from 0 to 59
	* @return a {@code ZonedDateTime} based on this date-time with the requested second, not null
	* @throws DateTimeException if the second value is invalid
	*/
	public ZonedDateTime withSecond(int second) {
	return resolveLocal(dateTime.withSecond(second));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the nano-of-second altered.
	* <p>
	* This operates on the local time-line,
	* {@linkplain LocalDateTime#withNano(int) changing the time} of the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param nanoOfSecond the nano-of-second to set in the result, from 0 to 999,999,999
	* @return a {@code ZonedDateTime} based on this date-time with the requested nanosecond, not null
	* @throws DateTimeException if the nano value is invalid
	*/
	public ZonedDateTime withNano(int nanoOfSecond) {
	return resolveLocal(dateTime.withNano(nanoOfSecond));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the time truncated.
	* <p>
	* Truncation returns a copy of the original date-time with fields
	* smaller than the specified unit set to zero.
	* For example, truncating with the {@link ChronoUnit#MINUTES minutes} unit
	* will set the second-of-minute and nano-of-second field to zero.
	* <p>
	* The unit must have a {@linkplain TemporalUnit#getDuration() duration}
	* that divides into the length of a standard day without remainder.
	* This includes all supplied time units on {@link ChronoUnit} and
	* {@link ChronoUnit#DAYS DAYS}. Other units throw an exception.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#truncatedTo(TemporalUnit) truncating}
	* the underlying local date-time. This is then converted back to a
	* {@code ZonedDateTime}, using the zone ID to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param unit the unit to truncate to, not null
	* @return a {@code ZonedDateTime} based on this date-time with the time truncated, not null
	* @throws DateTimeException if unable to truncate
	* @throws UnsupportedTemporalTypeException if the unit is not supported
	*/
	public ZonedDateTime truncatedTo(TemporalUnit unit) {
	return resolveLocal(dateTime.truncatedTo(unit));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this date-time with the specified amount added.
	* <p>
	* This returns a {@code ZonedDateTime}, based on this one, with the specified amount added.
	* The amount is typically {@link Period} or {@link Duration} but may be
	* any other type implementing the {@link TemporalAmount} interface.
	* <p>
	* The calculation is delegated to the amount object by calling
	* {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
	* to implement the addition in any way it wishes, however it typically
	* calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
	* of the amount implementation to determine if it can be successfully added.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param amountToAdd the amount to add, not null
	* @return a {@code ZonedDateTime} based on this date-time with the addition made, not null
	* @throws DateTimeException if the addition cannot be made
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime plus(TemporalAmount amountToAdd) {
	if (amountToAdd instanceof Period) {
	Period periodToAdd = (Period) amountToAdd;
	return resolveLocal(dateTime.plus(periodToAdd));
	}
	Objects.requireNonNull(amountToAdd, "amountToAdd");
	return (ZonedDateTime) amountToAdd.addTo(this);
	}

	/**
	* Returns a copy of this date-time with the specified amount added.
	* <p>
	* This returns a {@code ZonedDateTime}, based on this one, with the amount
	* in terms of the unit added. If it is not possible to add the amount, because the
	* unit is not supported or for some other reason, an exception is thrown.
	* <p>
	* If the field is a {@link ChronoUnit} then the addition is implemented here.
	* The zone is not part of the calculation and will be unchanged in the result.
	* The calculation for date and time units differ.
	* <p>
	* Date units operate on the local time-line.
	* The period is first added to the local date-time, then converted back
	* to a zoned date-time using the zone ID.
	* The conversion uses {@link #ofLocal(LocalDateTime, ZoneId, ZoneOffset)}
	* with the offset before the addition.
	* <p>
	* Time units operate on the instant time-line.
	* The period is first added to the local date-time, then converted back to
	* a zoned date-time using the zone ID.
	* The conversion uses {@link #ofInstant(LocalDateTime, ZoneOffset, ZoneId)}
	* with the offset before the addition.
	* <p>
	* If the field is not a {@code ChronoUnit}, then the result of this method
	* is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
	* passing {@code this} as the argument. In this case, the unit determines
	* whether and how to perform the addition.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param amountToAdd the amount of the unit to add to the result, may be negative
	* @param unit the unit of the amount to add, not null
	* @return a {@code ZonedDateTime} based on this date-time with the specified amount added, not null
	* @throws DateTimeException if the addition cannot be made
	* @throws UnsupportedTemporalTypeException if the unit is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime plus(long amountToAdd, TemporalUnit unit) {
	if (unit instanceof ChronoUnit) {
	if (unit.isDateBased()) {
	return resolveLocal(dateTime.plus(amountToAdd, unit));
	} else {
	return resolveInstant(dateTime.plus(amountToAdd, unit));
	}
	}
	return unit.addTo(this, amountToAdd);
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of years added.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#plusYears(long) adding years} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param years the years to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the years added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusYears(long years) {
	return resolveLocal(dateTime.plusYears(years));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of months added.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#plusMonths(long) adding months} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param months the months to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the months added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusMonths(long months) {
	return resolveLocal(dateTime.plusMonths(months));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of weeks added.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#plusWeeks(long) adding weeks} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param weeks the weeks to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the weeks added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusWeeks(long weeks) {
	return resolveLocal(dateTime.plusWeeks(weeks));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of days added.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#plusDays(long) adding days} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param days the days to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the days added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusDays(long days) {
	return resolveLocal(dateTime.plusDays(days));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of hours added.
	* <p>
	* This operates on the instant time-line, such that adding one hour will
	* always be a duration of one hour later.
	* This may cause the local date-time to change by an amount other than one hour.
	* Note that this is a different approach to that used by days, months and years,
	* thus adding one day is not the same as adding 24 hours.
	* <p>
	* For example, consider a time-zone where the spring DST cutover means that the
	* local times 01:00 to 01:59 occur twice changing from offset +02:00 to +01:00.
	* <ul>
	* <li>Adding one hour to 00:30+02:00 will result in 01:30+02:00
	* <li>Adding one hour to 01:30+02:00 will result in 01:30+01:00
	* <li>Adding one hour to 01:30+01:00 will result in 02:30+01:00
	* <li>Adding three hours to 00:30+02:00 will result in 02:30+01:00
	* </ul>
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param hours the hours to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the hours added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusHours(long hours) {
	return resolveInstant(dateTime.plusHours(hours));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of minutes added.
	* <p>
	* This operates on the instant time-line, such that adding one minute will
	* always be a duration of one minute later.
	* This may cause the local date-time to change by an amount other than one minute.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param minutes the minutes to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the minutes added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusMinutes(long minutes) {
	return resolveInstant(dateTime.plusMinutes(minutes));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of seconds added.
	* <p>
	* This operates on the instant time-line, such that adding one second will
	* always be a duration of one second later.
	* This may cause the local date-time to change by an amount other than one second.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param seconds the seconds to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the seconds added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusSeconds(long seconds) {
	return resolveInstant(dateTime.plusSeconds(seconds));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of nanoseconds added.
	* <p>
	* This operates on the instant time-line, such that adding one nano will
	* always be a duration of one nano later.
	* This may cause the local date-time to change by an amount other than one nano.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param nanos the nanos to add, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the nanoseconds added, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime plusNanos(long nanos) {
	return resolveInstant(dateTime.plusNanos(nanos));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this date-time with the specified amount subtracted.
	* <p>
	* This returns a {@code ZonedDateTime}, based on this one, with the specified amount subtracted.
	* The amount is typically {@link Period} or {@link Duration} but may be
	* any other type implementing the {@link TemporalAmount} interface.
	* <p>
	* The calculation is delegated to the amount object by calling
	* {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
	* to implement the subtraction in any way it wishes, however it typically
	* calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
	* of the amount implementation to determine if it can be successfully subtracted.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param amountToSubtract the amount to subtract, not null
	* @return a {@code ZonedDateTime} based on this date-time with the subtraction made, not null
	* @throws DateTimeException if the subtraction cannot be made
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime minus(TemporalAmount amountToSubtract) {
	if (amountToSubtract instanceof Period) {
	Period periodToSubtract = (Period) amountToSubtract;
	return resolveLocal(dateTime.minus(periodToSubtract));
	}
	Objects.requireNonNull(amountToSubtract, "amountToSubtract");
	return (ZonedDateTime) amountToSubtract.subtractFrom(this);
	}

	/**
	* Returns a copy of this date-time with the specified amount subtracted.
	* <p>
	* This returns a {@code ZonedDateTime}, based on this one, with the amount
	* in terms of the unit subtracted. If it is not possible to subtract the amount,
	* because the unit is not supported or for some other reason, an exception is thrown.
	* <p>
	* The calculation for date and time units differ.
	* <p>
	* Date units operate on the local time-line.
	* The period is first subtracted from the local date-time, then converted back
	* to a zoned date-time using the zone ID.
	* The conversion uses {@link #ofLocal(LocalDateTime, ZoneId, ZoneOffset)}
	* with the offset before the subtraction.
	* <p>
	* Time units operate on the instant time-line.
	* The period is first subtracted from the local date-time, then converted back to
	* a zoned date-time using the zone ID.
	* The conversion uses {@link #ofInstant(LocalDateTime, ZoneOffset, ZoneId)}
	* with the offset before the subtraction.
	* <p>
	* This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
	* See that method for a full description of how addition, and thus subtraction, works.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param amountToSubtract the amount of the unit to subtract from the result, may be negative
	* @param unit the unit of the amount to subtract, not null
	* @return a {@code ZonedDateTime} based on this date-time with the specified amount subtracted, not null
	* @throws DateTimeException if the subtraction cannot be made
	* @throws UnsupportedTemporalTypeException if the unit is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public ZonedDateTime minus(long amountToSubtract, TemporalUnit unit) {
	return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of years subtracted.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#minusYears(long) subtracting years} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param years the years to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the years subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusYears(long years) {
	return (years == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-years));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of months subtracted.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#minusMonths(long) subtracting months} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param months the months to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the months subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusMonths(long months) {
	return (months == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-months));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of weeks subtracted.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#minusWeeks(long) subtracting weeks} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param weeks the weeks to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the weeks subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusWeeks(long weeks) {
	return (weeks == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeks));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of days subtracted.
	* <p>
	* This operates on the local time-line,
	* {@link LocalDateTime#minusDays(long) subtracting days} to the local date-time.
	* This is then converted back to a {@code ZonedDateTime}, using the zone ID
	* to obtain the offset.
	* <p>
	* When converting back to {@code ZonedDateTime}, if the local date-time is in an overlap,
	* then the offset will be retained if possible, otherwise the earlier offset will be used.
	* If in a gap, the local date-time will be adjusted forward by the length of the gap.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param days the days to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the days subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusDays(long days) {
	return (days == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-days));
	}

	//-----------------------------------------------------------------------
	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of hours subtracted.
	* <p>
	* This operates on the instant time-line, such that subtracting one hour will
	* always be a duration of one hour earlier.
	* This may cause the local date-time to change by an amount other than one hour.
	* Note that this is a different approach to that used by days, months and years,
	* thus subtracting one day is not the same as adding 24 hours.
	* <p>
	* For example, consider a time-zone where the spring DST cutover means that the
	* local times 01:00 to 01:59 occur twice changing from offset +02:00 to +01:00.
	* <ul>
	* <li>Subtracting one hour from 02:30+01:00 will result in 01:30+02:00
	* <li>Subtracting one hour from 01:30+01:00 will result in 01:30+02:00
	* <li>Subtracting one hour from 01:30+02:00 will result in 00:30+01:00
	* <li>Subtracting three hours from 02:30+01:00 will result in 00:30+02:00
	* </ul>
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param hours the hours to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the hours subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusHours(long hours) {
	return (hours == Long.MIN_VALUE ? plusHours(Long.MAX_VALUE).plusHours(1) : plusHours(-hours));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of minutes subtracted.
	* <p>
	* This operates on the instant time-line, such that subtracting one minute will
	* always be a duration of one minute earlier.
	* This may cause the local date-time to change by an amount other than one minute.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param minutes the minutes to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the minutes subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusMinutes(long minutes) {
	return (minutes == Long.MIN_VALUE ? plusMinutes(Long.MAX_VALUE).plusMinutes(1) : plusMinutes(-minutes));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of seconds subtracted.
	* <p>
	* This operates on the instant time-line, such that subtracting one second will
	* always be a duration of one second earlier.
	* This may cause the local date-time to change by an amount other than one second.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param seconds the seconds to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the seconds subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusSeconds(long seconds) {
	return (seconds == Long.MIN_VALUE ? plusSeconds(Long.MAX_VALUE).plusSeconds(1) : plusSeconds(-seconds));
	}

	/**
	* Returns a copy of this {@code ZonedDateTime} with the specified number of nanoseconds subtracted.
	* <p>
	* This operates on the instant time-line, such that subtracting one nano will
	* always be a duration of one nano earlier.
	* This may cause the local date-time to change by an amount other than one nano.
	* Note that this is a different approach to that used by days, months and years.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param nanos the nanos to subtract, may be negative
	* @return a {@code ZonedDateTime} based on this date-time with the nanoseconds subtracted, not null
	* @throws DateTimeException if the result exceeds the supported date range
	*/
	public ZonedDateTime minusNanos(long nanos) {
	return (nanos == Long.MIN_VALUE ? plusNanos(Long.MAX_VALUE).plusNanos(1) : plusNanos(-nanos));
	}

	//-----------------------------------------------------------------------
	/**
	* 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 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 // override for Javadoc
	public <R> R query(TemporalQuery<R> query) {
	if (query == TemporalQueries.localDate()) {
	return (R) toLocalDate();
	}
	return ChronoZonedDateTime.super.query(query);
	}

	/**
	* Calculates the amount of time until another date-time in terms of the specified unit.
	* <p>
	* This calculates the amount of time between two {@code ZonedDateTime}
	* objects in terms of a single {@code TemporalUnit}.
	* The start and end points are {@code this} and the specified date-time.
	* The result will be negative if the end is before the start.
	* For example, the amount in days between two date-times can be calculated
	* using {@code startDateTime.until(endDateTime, DAYS)}.
	* <p>
	* The {@code Temporal} passed to this method is converted to a
	* {@code ZonedDateTime} using {@link #from(TemporalAccessor)}.
	* If the time-zone differs between the two zoned date-times, the specified
	* end date-time is normalized to have the same zone as this date-time.
	* <p>
	* The calculation returns a whole number, representing the number of
	* complete units between the two date-times.
	* For example, the amount in months between 2012-06-15T00:00Z and 2012-08-14T23:59Z
	* will only be one month as it is one minute short of two months.
	* <p>
	* There are two equivalent ways of using this method.
	* The first is to invoke this method.
	* The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
	* <pre>
	* // these two lines are equivalent
	* amount = start.until(end, MONTHS);
	* amount = MONTHS.between(start, end);
	* </pre>
	* The choice should be made based on which makes the code more readable.
	* <p>
	* The calculation is implemented in this method for {@link ChronoUnit}.
	* The units {@code NANOS}, {@code MICROS}, {@code MILLIS}, {@code SECONDS},
	* {@code MINUTES}, {@code HOURS} and {@code HALF_DAYS}, {@code DAYS},
	* {@code WEEKS}, {@code MONTHS}, {@code YEARS}, {@code DECADES},
	* {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS} are supported.
	* Other {@code ChronoUnit} values will throw an exception.
	* <p>
	* The calculation for date and time units differ.
	* <p>
	* Date units operate on the local time-line, using the local date-time.
	* For example, the period from noon on day 1 to noon the following day
	* in days will always be counted as exactly one day, irrespective of whether
	* there was a daylight savings change or not.
	* <p>
	* Time units operate on the instant time-line.
	* The calculation effectively converts both zoned date-times to instants
	* and then calculates the period between the instants.
	* For example, the period from noon on day 1 to noon the following day
	* in hours may be 23, 24 or 25 hours (or some other amount) depending on
	* whether there was a daylight savings change or not.
	* <p>
	* If the unit is not a {@code ChronoUnit}, then the result of this method
	* is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
	* passing {@code this} as the first argument and the converted input temporal
	* as the second argument.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param endExclusive the end date, exclusive, which is converted to a {@code ZonedDateTime}, not null
	* @param unit the unit to measure the amount in, not null
	* @return the amount of time between this date-time and the end date-time
	* @throws DateTimeException if the amount cannot be calculated, or the end
	* temporal cannot be converted to a {@code ZonedDateTime}
	* @throws UnsupportedTemporalTypeException if the unit is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public long until(Temporal endExclusive, TemporalUnit unit) {
	ZonedDateTime end = ZonedDateTime.from(endExclusive);
	if (unit instanceof ChronoUnit) {
	end = end.withZoneSameInstant(zone);
	if (unit.isDateBased()) {
	return dateTime.until(end.dateTime, unit);
	} else {
	return toOffsetDateTime().until(end.toOffsetDateTime(), unit);
	}
	}
	return unit.between(this, end);
	}

	/**
	* Formats this date-time using the specified formatter.
	* <p>
	* This date-time will be passed to the formatter to produce a string.
	*
	* @param formatter the formatter to use, not null
	* @return the formatted date-time string, not null
	* @throws DateTimeException if an error occurs during printing
	*/
	@Override // override for Javadoc and performance
	public String format(DateTimeFormatter formatter) {
	Objects.requireNonNull(formatter, "formatter");
	return formatter.format(this);
	}

	//-----------------------------------------------------------------------
	/**
	* Converts this date-time to an {@code OffsetDateTime}.
	* <p>
	* This creates an offset date-time using the local date-time and offset.
	* The zone ID is ignored.
	*
	* @return an offset date-time representing the same local date-time and offset, not null
	*/
	public OffsetDateTime toOffsetDateTime() {
	return OffsetDateTime.of(dateTime, offset);
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if this date-time is equal to another date-time.
	* <p>
	* The comparison is based on the offset date-time and the zone.
	* Only objects of type {@code ZonedDateTime} are compared, other types return false.
	*
	* @param obj the object to check, null returns false
	* @return true if this is equal to the other date-time
	*/
	@Override
	public boolean equals(Object obj) {
	if (this == obj) {
	return true;
	}
	if (obj instanceof ZonedDateTime) {
	ZonedDateTime other = (ZonedDateTime) obj;
	return dateTime.equals(other.dateTime) &&
	offset.equals(other.offset) &&
	zone.equals(other.zone);
	}
	return false;
	}

	/**
	* A hash code for this date-time.
	*
	* @return a suitable hash code
	*/
	@Override
	public int hashCode() {
	return dateTime.hashCode() ^ offset.hashCode() ^ Integer.rotateLeft(zone.hashCode(), 3);
	}

	//-----------------------------------------------------------------------
	/**
	* Outputs this date-time as a {@code String}, such as
	* {@code 2007-12-03T10:15:30+01:00[Europe/Paris]}.
	* <p>
	* The format consists of the {@code LocalDateTime} followed by the {@code ZoneOffset}.
	* If the {@code ZoneId} is not the same as the offset, then the ID is output.
	* The output is compatible with ISO-8601 if the offset and ID are the same.
	*
	* @return a string representation of this date-time, not null
	*/
	@Override // override for Javadoc
	public String toString() {
	String str = dateTime.toString() + offset.toString();
	if (offset != zone) {
	str += '[' + zone.toString() + ']';
	}
	return str;
	}

	//-----------------------------------------------------------------------
	/**
	* Writes the object using a
	* <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
	* @serialData
	* <pre>
	* out.writeByte(6); // identifies a ZonedDateTime
	* // the <a href="../../serialized-form.html#java.time.LocalDateTime">dateTime</a> excluding the one byte header
	* // the <a href="../../serialized-form.html#java.time.ZoneOffset">offset</a> excluding the one byte header
	* // the <a href="../../serialized-form.html#java.time.ZoneId">zone ID</a> excluding the one byte header
	* </pre>
	*
	* @return the instance of {@code Ser}, not null
	*/
	private Object writeReplace() {
	return new Ser(Ser.ZONE_DATE_TIME_TYPE, this);
	}

	/**
	* Defend against malicious streams.
	*
	* @param s the stream to read
	* @throws InvalidObjectException always
	*/
	private void readObject(ObjectInputStream s) throws InvalidObjectException {
	throw new InvalidObjectException("Deserialization via serialization delegate");
	}

	void writeExternal(DataOutput out) throws IOException {
	dateTime.writeExternal(out);
	offset.writeExternal(out);
	zone.write(out);
	}

	static ZonedDateTime readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
	LocalDateTime dateTime = LocalDateTime.readExternal(in);
	ZoneOffset offset = ZoneOffset.readExternal(in);
	ZoneId zone = (ZoneId) Ser.read(in);
	return ZonedDateTime.ofLenient(dateTime, offset, zone);
	}

	}

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