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	/*
	* Copyright (c) 2012, 2016, 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
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	/*
	* 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
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	package java.time;

	import static java.time.LocalTime.MINUTES_PER_HOUR;
	import static java.time.LocalTime.SECONDS_PER_HOUR;
	import static java.time.LocalTime.SECONDS_PER_MINUTE;
	import static java.time.temporal.ChronoField.OFFSET_SECONDS;

	import java.io.DataInput;
	import java.io.DataOutput;
	import java.io.IOException;
	import java.io.InvalidObjectException;
	import java.io.ObjectInputStream;
	import java.io.Serializable;
	import java.time.temporal.ChronoField;
	import java.time.temporal.Temporal;
	import java.time.temporal.TemporalAccessor;
	import java.time.temporal.TemporalAdjuster;
	import java.time.temporal.TemporalField;
	import java.time.temporal.TemporalQueries;
	import java.time.temporal.TemporalQuery;
	import java.time.temporal.UnsupportedTemporalTypeException;
	import java.time.temporal.ValueRange;
	import java.time.zone.ZoneRules;
	import java.util.Objects;
	import java.util.concurrent.ConcurrentHashMap;
	import java.util.concurrent.ConcurrentMap;

	/**
	* A time-zone offset from Greenwich/UTC, such as {@code +02:00}.
	* <p>
	* A time-zone offset is the amount of time that a time-zone differs from Greenwich/UTC.
	* This is usually a fixed number of hours and minutes.
	* <p>
	* Different parts of the world have different time-zone offsets.
	* The rules for how offsets vary by place and time of year are captured in the
	* {@link ZoneId} class.
	* <p>
	* For example, Paris is one hour ahead of Greenwich/UTC in winter and two hours
	* ahead in summer. The {@code ZoneId} instance for Paris will reference two
	* {@code ZoneOffset} instances - a {@code +01:00} instance for winter,
	* and a {@code +02:00} instance for summer.
	* <p>
	* In 2008, time-zone offsets around the world extended from -12:00 to +14:00.
	* To prevent any problems with that range being extended, yet still provide
	* validation, the range of offsets is restricted to -18:00 to 18:00 inclusive.
	* <p>
	* This class is designed for use with the ISO calendar system.
	* The fields of hours, minutes and seconds make assumptions that are valid for the
	* standard ISO definitions of those fields. This class may be used with other
	* calendar systems providing the definition of the time fields matches those
	* of the ISO calendar system.
	* <p>
	* Instances of {@code ZoneOffset} must be compared using {@link #equals}.
	* Implementations may choose to cache certain common offsets, however
	* applications must not rely on such caching.
	*
	* <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 ZoneOffset} may have unpredictable results and should be avoided.
	* The {@code equals} method should be used for comparisons.
	*
	* @implSpec
	* This class is immutable and thread-safe.
	*
	* @since 1.8
	*/
	public final class ZoneOffset
	extends ZoneId
	implements TemporalAccessor, TemporalAdjuster, Comparable<ZoneOffset>, Serializable {

	/** Cache of time-zone offset by offset in seconds. */
	private static final ConcurrentMap<Integer, ZoneOffset> SECONDS_CACHE = new ConcurrentHashMap<>(16, 0.75f, 4);
	/** Cache of time-zone offset by ID. */
	private static final ConcurrentMap<String, ZoneOffset> ID_CACHE = new ConcurrentHashMap<>(16, 0.75f, 4);

	/**
	* The abs maximum seconds.
	*/
	private static final int MAX_SECONDS = 18 * SECONDS_PER_HOUR;
	/**
	* Serialization version.
	*/
	private static final long serialVersionUID = 2357656521762053153L;

	/**
	* The time-zone offset for UTC, with an ID of 'Z'.
	*/
	public static final ZoneOffset UTC = ZoneOffset.ofTotalSeconds(0);
	/**
	* Constant for the maximum supported offset.
	*/
	public static final ZoneOffset MIN = ZoneOffset.ofTotalSeconds(-MAX_SECONDS);
	/**
	* Constant for the maximum supported offset.
	*/
	public static final ZoneOffset MAX = ZoneOffset.ofTotalSeconds(MAX_SECONDS);

	/**
	* The total offset in seconds.
	*/
	private final int totalSeconds;
	/**
	* The string form of the time-zone offset.
	*/
	private final transient String id;

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZoneOffset} using the ID.
	* <p>
	* This method parses the string ID of a {@code ZoneOffset} to
	* return an instance. The parsing accepts all the formats generated by
	* {@link #getId()}, plus some additional formats:
	* <ul>
	* <li>{@code Z} - for UTC
	* <li>{@code +h}
	* <li>{@code +hh}
	* <li>{@code +hh:mm}
	* <li>{@code -hh:mm}
	* <li>{@code +hhmm}
	* <li>{@code -hhmm}
	* <li>{@code +hh:mm:ss}
	* <li>{@code -hh:mm:ss}
	* <li>{@code +hhmmss}
	* <li>{@code -hhmmss}
	* </ul>
	* Note that ± means either the plus or minus symbol.
	* <p>
	* The ID of the returned offset will be normalized to one of the formats
	* described by {@link #getId()}.
	* <p>
	* The maximum supported range is from +18:00 to -18:00 inclusive.
	*
	* @param offsetId the offset ID, not null
	* @return the zone-offset, not null
	* @throws DateTimeException if the offset ID is invalid
	*/
	@SuppressWarnings("fallthrough")
	public static ZoneOffset of(String offsetId) {
	Objects.requireNonNull(offsetId, "offsetId");
	// "Z" is always in the cache
	ZoneOffset offset = ID_CACHE.get(offsetId);
	if (offset != null) {
	return offset;
	}

	// parse - +h, +hh, +hhmm, +hh:mm, +hhmmss, +hh:mm:ss
	final int hours, minutes, seconds;
	switch (offsetId.length()) {
	case 2:
	offsetId = offsetId.charAt(0) + "0" + offsetId.charAt(1); // fallthru
	case 3:
	hours = parseNumber(offsetId, 1, false);
	minutes = 0;
	seconds = 0;
	break;
	case 5:
	hours = parseNumber(offsetId, 1, false);
	minutes = parseNumber(offsetId, 3, false);
	seconds = 0;
	break;
	case 6:
	hours = parseNumber(offsetId, 1, false);
	minutes = parseNumber(offsetId, 4, true);
	seconds = 0;
	break;
	case 7:
	hours = parseNumber(offsetId, 1, false);
	minutes = parseNumber(offsetId, 3, false);
	seconds = parseNumber(offsetId, 5, false);
	break;
	case 9:
	hours = parseNumber(offsetId, 1, false);
	minutes = parseNumber(offsetId, 4, true);
	seconds = parseNumber(offsetId, 7, true);
	break;
	default:
	throw new DateTimeException("Invalid ID for ZoneOffset, invalid format: " + offsetId);
	}
	char first = offsetId.charAt(0);
	if (first != '+' && first != '-') {
	throw new DateTimeException("Invalid ID for ZoneOffset, plus/minus not found when expected: " + offsetId);
	}
	if (first == '-') {
	return ofHoursMinutesSeconds(-hours, -minutes, -seconds);
	} else {
	return ofHoursMinutesSeconds(hours, minutes, seconds);
	}
	}

	/**
	* Parse a two digit zero-prefixed number.
	*
	* @param offsetId the offset ID, not null
	* @param pos the position to parse, valid
	* @param precededByColon should this number be prefixed by a precededByColon
	* @return the parsed number, from 0 to 99
	*/
	private static int parseNumber(CharSequence offsetId, int pos, boolean precededByColon) {
	if (precededByColon && offsetId.charAt(pos - 1) != ':') {
	throw new DateTimeException("Invalid ID for ZoneOffset, colon not found when expected: " + offsetId);
	}
	char ch1 = offsetId.charAt(pos);
	char ch2 = offsetId.charAt(pos + 1);
	if (ch1 < '0' \|\| ch1 > '9' \|\| ch2 < '0' \|\| ch2 > '9') {
	throw new DateTimeException("Invalid ID for ZoneOffset, non numeric characters found: " + offsetId);
	}
	return (ch1 - 48) * 10 + (ch2 - 48);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZoneOffset} using an offset in hours.
	*
	* @param hours the time-zone offset in hours, from -18 to +18
	* @return the zone-offset, not null
	* @throws DateTimeException if the offset is not in the required range
	*/
	public static ZoneOffset ofHours(int hours) {
	return ofHoursMinutesSeconds(hours, 0, 0);
	}

	/**
	* Obtains an instance of {@code ZoneOffset} using an offset in
	* hours and minutes.
	* <p>
	* The sign of the hours and minutes components must match.
	* Thus, if the hours is negative, the minutes must be negative or zero.
	* If the hours is zero, the minutes may be positive, negative or zero.
	*
	* @param hours the time-zone offset in hours, from -18 to +18
	* @param minutes the time-zone offset in minutes, from 0 to ±59, sign matches hours
	* @return the zone-offset, not null
	* @throws DateTimeException if the offset is not in the required range
	*/
	public static ZoneOffset ofHoursMinutes(int hours, int minutes) {
	return ofHoursMinutesSeconds(hours, minutes, 0);
	}

	/**
	* Obtains an instance of {@code ZoneOffset} using an offset in
	* hours, minutes and seconds.
	* <p>
	* The sign of the hours, minutes and seconds components must match.
	* Thus, if the hours is negative, the minutes and seconds must be negative or zero.
	*
	* @param hours the time-zone offset in hours, from -18 to +18
	* @param minutes the time-zone offset in minutes, from 0 to ±59, sign matches hours and seconds
	* @param seconds the time-zone offset in seconds, from 0 to ±59, sign matches hours and minutes
	* @return the zone-offset, not null
	* @throws DateTimeException if the offset is not in the required range
	*/
	public static ZoneOffset ofHoursMinutesSeconds(int hours, int minutes, int seconds) {
	validate(hours, minutes, seconds);
	int totalSeconds = totalSeconds(hours, minutes, seconds);
	return ofTotalSeconds(totalSeconds);
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZoneOffset} from a temporal object.
	* <p>
	* This obtains an offset 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 ZoneOffset}.
	* <p>
	* A {@code TemporalAccessor} represents some form of date and time information.
	* This factory converts the arbitrary temporal object to an instance of {@code ZoneOffset}.
	* <p>
	* The conversion uses the {@link TemporalQueries#offset()} query, which relies
	* on extracting the {@link ChronoField#OFFSET_SECONDS OFFSET_SECONDS} field.
	* <p>
	* This method matches the signature of the functional interface {@link TemporalQuery}
	* allowing it to be used as a query via method reference, {@code ZoneOffset::from}.
	*
	* @param temporal the temporal object to convert, not null
	* @return the zone-offset, not null
	* @throws DateTimeException if unable to convert to an {@code ZoneOffset}
	*/
	public static ZoneOffset from(TemporalAccessor temporal) {
	Objects.requireNonNull(temporal, "temporal");
	ZoneOffset offset = temporal.query(TemporalQueries.offset());
	if (offset == null) {
	throw new DateTimeException("Unable to obtain ZoneOffset from TemporalAccessor: " +
	temporal + " of type " + temporal.getClass().getName());
	}
	return offset;
	}

	//-----------------------------------------------------------------------
	/**
	* Validates the offset fields.
	*
	* @param hours the time-zone offset in hours, from -18 to +18
	* @param minutes the time-zone offset in minutes, from 0 to ±59
	* @param seconds the time-zone offset in seconds, from 0 to ±59
	* @throws DateTimeException if the offset is not in the required range
	*/
	private static void validate(int hours, int minutes, int seconds) {
	if (hours < -18 \|\| hours > 18) {
	throw new DateTimeException("Zone offset hours not in valid range: value " + hours +
	" is not in the range -18 to 18");
	}
	if (hours > 0) {
	if (minutes < 0 \|\| seconds < 0) {
	throw new DateTimeException("Zone offset minutes and seconds must be positive because hours is positive");
	}
	} else if (hours < 0) {
	if (minutes > 0 \|\| seconds > 0) {
	throw new DateTimeException("Zone offset minutes and seconds must be negative because hours is negative");
	}
	} else if ((minutes > 0 && seconds < 0) \|\| (minutes < 0 && seconds > 0)) {
	throw new DateTimeException("Zone offset minutes and seconds must have the same sign");
	}
	if (minutes < -59 \|\| minutes > 59) {
	throw new DateTimeException("Zone offset minutes not in valid range: value " +
	minutes + " is not in the range -59 to 59");
	}
	if (seconds < -59 \|\| seconds > 59) {
	throw new DateTimeException("Zone offset seconds not in valid range: value " +
	seconds + " is not in the range -59 to 59");
	}
	if (Math.abs(hours) == 18 && (minutes \| seconds) != 0) {
	throw new DateTimeException("Zone offset not in valid range: -18:00 to +18:00");
	}
	}

	/**
	* Calculates the total offset in seconds.
	*
	* @param hours the time-zone offset in hours, from -18 to +18
	* @param minutes the time-zone offset in minutes, from 0 to ±59, sign matches hours and seconds
	* @param seconds the time-zone offset in seconds, from 0 to ±59, sign matches hours and minutes
	* @return the total in seconds
	*/
	private static int totalSeconds(int hours, int minutes, int seconds) {
	return hours * SECONDS_PER_HOUR + minutes * SECONDS_PER_MINUTE + seconds;
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code ZoneOffset} specifying the total offset in seconds
	* <p>
	* The offset must be in the range {@code -18:00} to {@code +18:00}, which corresponds to -64800 to +64800.
	*
	* @param totalSeconds the total time-zone offset in seconds, from -64800 to +64800
	* @return the ZoneOffset, not null
	* @throws DateTimeException if the offset is not in the required range
	*/
	public static ZoneOffset ofTotalSeconds(int totalSeconds) {
	if (totalSeconds < -MAX_SECONDS \|\| totalSeconds > MAX_SECONDS) {
	throw new DateTimeException("Zone offset not in valid range: -18:00 to +18:00");
	}
	if (totalSeconds % (15 * SECONDS_PER_MINUTE) == 0) {
	Integer totalSecs = totalSeconds;
	ZoneOffset result = SECONDS_CACHE.get(totalSecs);
	if (result == null) {
	result = new ZoneOffset(totalSeconds);
	SECONDS_CACHE.putIfAbsent(totalSecs, result);
	result = SECONDS_CACHE.get(totalSecs);
	ID_CACHE.putIfAbsent(result.getId(), result);
	}
	return result;
	} else {
	return new ZoneOffset(totalSeconds);
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Constructor.
	*
	* @param totalSeconds the total time-zone offset in seconds, from -64800 to +64800
	*/
	private ZoneOffset(int totalSeconds) {
	super();
	this.totalSeconds = totalSeconds;
	id = buildId(totalSeconds);
	}

	private static String buildId(int totalSeconds) {
	if (totalSeconds == 0) {
	return "Z";
	} else {
	int absTotalSeconds = Math.abs(totalSeconds);
	StringBuilder buf = new StringBuilder();
	int absHours = absTotalSeconds / SECONDS_PER_HOUR;
	int absMinutes = (absTotalSeconds / SECONDS_PER_MINUTE) % MINUTES_PER_HOUR;
	buf.append(totalSeconds < 0 ? "-" : "+")
	.append(absHours < 10 ? "0" : "").append(absHours)
	.append(absMinutes < 10 ? ":0" : ":").append(absMinutes);
	int absSeconds = absTotalSeconds % SECONDS_PER_MINUTE;
	if (absSeconds != 0) {
	buf.append(absSeconds < 10 ? ":0" : ":").append(absSeconds);
	}
	return buf.toString();
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the total zone offset in seconds.
	* <p>
	* This is the primary way to access the offset amount.
	* It returns the total of the hours, minutes and seconds fields as a
	* single offset that can be added to a time.
	*
	* @return the total zone offset amount in seconds
	*/
	public int getTotalSeconds() {
	return totalSeconds;
	}

	/**
	* Gets the normalized zone offset ID.
	* <p>
	* The ID is minor variation to the standard ISO-8601 formatted string
	* for the offset. There are three formats:
	* <ul>
	* <li>{@code Z} - for UTC (ISO-8601)
	* <li>{@code +hh:mm} or {@code -hh:mm} - if the seconds are zero (ISO-8601)
	* <li>{@code +hh:mm:ss} or {@code -hh:mm:ss} - if the seconds are non-zero (not ISO-8601)
	* </ul>
	*
	* @return the zone offset ID, not null
	*/
	@Override
	public String getId() {
	return id;
	}

	/**
	* Gets the associated time-zone rules.
	* <p>
	* The rules will always return this offset when queried.
	* The implementation class is immutable, thread-safe and serializable.
	*
	* @return the rules, not null
	*/
	@Override
	public ZoneRules getRules() {
	return ZoneRules.of(this);
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if the specified field is supported.
	* <p>
	* This checks if this offset can be queried for the specified field.
	* If false, then calling the {@link #range(TemporalField) range} and
	* {@link #get(TemporalField) get} methods will throw an exception.
	* <p>
	* If the field is a {@link ChronoField} then the query is implemented here.
	* The {@code OFFSET_SECONDS} field returns true.
	* 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 offset, false if not
	*/
	@Override
	public boolean isSupported(TemporalField field) {
	if (field instanceof ChronoField) {
	return field == OFFSET_SECONDS;
	}
	return field != null && field.isSupportedBy(this);
	}

	/**
	* 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 offset 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 // override for Javadoc
	public ValueRange range(TemporalField field) {
	return TemporalAccessor.super.range(field);
	}

	/**
	* Gets the value of the specified field from this offset as an {@code int}.
	* <p>
	* This queries this offset 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 {@code OFFSET_SECONDS} field returns the value of the offset.
	* 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 == OFFSET_SECONDS) {
	return totalSeconds;
	} else if (field instanceof ChronoField) {
	throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
	}
	return range(field).checkValidIntValue(getLong(field), field);
	}

	/**
	* Gets the value of the specified field from this offset as a {@code long}.
	* <p>
	* This queries this offset 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 {@code OFFSET_SECONDS} field returns the value of the offset.
	* 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 == OFFSET_SECONDS) {
	return totalSeconds;
	} else if (field instanceof ChronoField) {
	throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
	}
	return field.getFrom(this);
	}

	//-----------------------------------------------------------------------
	/**
	* Queries this offset using the specified query.
	* <p>
	* This queries this offset 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
	public <R> R query(TemporalQuery<R> query) {
	if (query == TemporalQueries.offset() \|\| query == TemporalQueries.zone()) {
	return (R) this;
	}
	return TemporalAccessor.super.query(query);
	}

	/**
	* Adjusts the specified temporal object to have the same offset as this object.
	* <p>
	* This returns a temporal object of the same observable type as the input
	* with the offset changed to be the same as this.
	* <p>
	* The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
	* passing {@link ChronoField#OFFSET_SECONDS} as the field.
	* <p>
	* In most cases, it is clearer to reverse the calling pattern by using
	* {@link Temporal#with(TemporalAdjuster)}:
	* <pre>
	* // these two lines are equivalent, but the second approach is recommended
	* temporal = thisOffset.adjustInto(temporal);
	* temporal = temporal.with(thisOffset);
	* </pre>
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param temporal the target object to be adjusted, not null
	* @return the adjusted object, not null
	* @throws DateTimeException if unable to make the adjustment
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public Temporal adjustInto(Temporal temporal) {
	return temporal.with(OFFSET_SECONDS, totalSeconds);
	}

	//-----------------------------------------------------------------------
	/**
	* Compares this offset to another offset in descending order.
	* <p>
	* The offsets are compared in the order that they occur for the same time
	* of day around the world. Thus, an offset of {@code +10:00} comes before an
	* offset of {@code +09:00} and so on down to {@code -18:00}.
	* <p>
	* The comparison is "consistent with equals", as defined by {@link Comparable}.
	*
	* @param other the other date to compare to, not null
	* @return the comparator value, negative if less, positive if greater
	* @throws NullPointerException if {@code other} is null
	*/
	@Override
	public int compareTo(ZoneOffset other) {
	// abs(totalSeconds) <= MAX_SECONDS, so no overflow can happen here
	return other.totalSeconds - totalSeconds;
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if this offset is equal to another offset.
	* <p>
	* The comparison is based on the amount of the offset in seconds.
	* This is equivalent to a comparison by ID.
	*
	* @param obj the object to check, null returns false
	* @return true if this is equal to the other offset
	*/
	@Override
	public boolean equals(Object obj) {
	if (this == obj) {
	return true;
	}
	if (obj instanceof ZoneOffset) {
	return totalSeconds == ((ZoneOffset) obj).totalSeconds;
	}
	return false;
	}

	/**
	* A hash code for this offset.
	*
	* @return a suitable hash code
	*/
	@Override
	public int hashCode() {
	return totalSeconds;
	}

	//-----------------------------------------------------------------------
	/**
	* Outputs this offset as a {@code String}, using the normalized ID.
	*
	* @return a string representation of this offset, not null
	*/
	@Override
	public String toString() {
	return id;
	}

	// -----------------------------------------------------------------------
	/**
	* Writes the object using a
	* <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
	* @serialData
	* <pre>
	* out.writeByte(8); // identifies a ZoneOffset
	* int offsetByte = totalSeconds % 900 == 0 ? totalSeconds / 900 : 127;
	* out.writeByte(offsetByte);
	* if (offsetByte == 127) {
	* out.writeInt(totalSeconds);
	* }
	* </pre>
	*
	* @return the instance of {@code Ser}, not null
	*/
	private Object writeReplace() {
	return new Ser(Ser.ZONE_OFFSET_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");
	}

	@Override
	void write(DataOutput out) throws IOException {
	out.writeByte(Ser.ZONE_OFFSET_TYPE);
	writeExternal(out);
	}

	void writeExternal(DataOutput out) throws IOException {
	final int offsetSecs = totalSeconds;
	int offsetByte = offsetSecs % 900 == 0 ? offsetSecs / 900 : 127; // compress to -72 to +72
	out.writeByte(offsetByte);
	if (offsetByte == 127) {
	out.writeInt(offsetSecs);
	}
	}

	static ZoneOffset readExternal(DataInput in) throws IOException {
	int offsetByte = in.readByte();
	return (offsetByte == 127 ? ZoneOffset.ofTotalSeconds(in.readInt()) : ZoneOffset.ofTotalSeconds(offsetByte * 900));
	}

	}

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