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/*
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 * 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.
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 * * 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.
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 * * 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.
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 * 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.NANOS_PER_HOUR;
import static java.time.LocalTime.NANOS_PER_MINUTE;
import static java.time.LocalTime.NANOS_PER_SECOND;
import static java.time.LocalTime.SECONDS_PER_DAY;
import static java.time.temporal.ChronoField.NANO_OF_DAY;
import static java.time.temporal.ChronoField.OFFSET_SECONDS;
import static java.time.temporal.ChronoUnit.NANOS;

import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
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.ZoneRules;
import java.util.Objects;

/**
 * A time with an offset from UTC/Greenwich in the ISO-8601 calendar system,
 * such as {@code 10:15:30+01:00}.
 * <p>
 * {@code OffsetTime} is an immutable date-time object that represents a time, often
 * viewed as hour-minute-second-offset.
 * This class stores all time fields, to a precision of nanoseconds,
 * as well as a zone offset.
 * For example, the value "13:45:30.123456789+02:00" can be stored
 * in an {@code OffsetTime}.
 *
 * <p>
 * This is a <a href="{@docRoot}/java.base/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 OffsetTime} 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 OffsetTime
 implements Temporal, TemporalAdjuster, Comparable<OffsetTime>, Serializable {

 /**
 * The minimum supported {@code OffsetTime}, '00:00:00+18:00'.
 * This is the time of midnight at the start of the day in the maximum offset
 * (larger offsets are earlier on the time-line).
 * This combines {@link LocalTime#MIN} and {@link ZoneOffset#MAX}.
 * This could be used by an application as a "far past" date.
 */
 public static final OffsetTime MIN = LocalTime.MIN.atOffset(ZoneOffset.MAX);
 /**
 * The maximum supported {@code OffsetTime}, '23:59:59.999999999-18:00'.
 * This is the time just before midnight at the end of the day in the minimum offset
 * (larger negative offsets are later on the time-line).
 * This combines {@link LocalTime#MAX} and {@link ZoneOffset#MIN}.
 * This could be used by an application as a "far future" date.
 */
 public static final OffsetTime MAX = LocalTime.MAX.atOffset(ZoneOffset.MIN);

 /**
 * Serialization version.
 */
 private static final long serialVersionUID = 7264499704384272492L;

 /**
 * The local date-time.
 */
 private final LocalTime time;
 /**
 * The offset from UTC/Greenwich.
 */
 private final ZoneOffset offset;

 //-----------------------------------------------------------------------
 /**
 * Obtains the current 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 time.
 * The offset will be calculated from 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 time using the system clock and default time-zone, not null
 */
 public static OffsetTime now() {
 return now(Clock.systemDefaultZone());
 }

 /**
 * Obtains the current 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 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 time using the system clock, not null
 */
 public static OffsetTime now(ZoneId zone) {
 return now(Clock.system(zone));
 }

 /**
 * Obtains the current time from the specified clock.
 * <p>
 * This will query the specified clock to obtain the current time.
 * The offset will be calculated from 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 time, not null
 */
 public static OffsetTime now(Clock clock) {
 Objects.requireNonNull(clock, "clock");
 final Instant now = clock.instant(); // called once
 return ofInstant(now, clock.getZone().getRules().getOffset(now));
 }

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code OffsetTime} from a local time and an offset.
 *
 * @param time the local time, not null
 * @param offset the zone offset, not null
 * @return the offset time, not null
 */
 public static OffsetTime of(LocalTime time, ZoneOffset offset) {
 return new OffsetTime(time, offset);
 }

 /**
 * Obtains an instance of {@code OffsetTime} from an hour, minute, second and nanosecond.
 * <p>
 * This creates an offset time with the four specified fields.
 * <p>
 * This method exists primarily for writing test cases.
 * Non test-code will typically use other methods to create an offset time.
 * {@code LocalTime} has two additional convenience variants of the
 * equivalent factory method taking fewer arguments.
 * They are not provided here to reduce the footprint of the API.
 *
 * @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 offset the zone offset, not null
 * @return the offset time, not null
 * @throws DateTimeException if the value of any field is out of range
 */
 public static OffsetTime of(int hour, int minute, int second, int nanoOfSecond, ZoneOffset offset) {
 return new OffsetTime(LocalTime.of(hour, minute, second, nanoOfSecond), offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code OffsetTime} from an {@code Instant} and zone ID.
 * <p>
 * This creates an offset time with the same instant as that specified.
 * Finding the offset from UTC/Greenwich is simple as there is only one valid
 * offset for each instant.
 * <p>
 * The date component of the instant is dropped during the conversion.
 * This means that the conversion can never fail due to the instant being
 * out of the valid range of dates.
 *
 * @param instant the instant to create the time from, not null
 * @param zone the time-zone, which may be an offset, not null
 * @return the offset time, not null
 */
 public static OffsetTime ofInstant(Instant instant, ZoneId zone) {
 Objects.requireNonNull(instant, "instant");
 Objects.requireNonNull(zone, "zone");
 ZoneRules rules = zone.getRules();
 ZoneOffset offset = rules.getOffset(instant);
 long localSecond = instant.getEpochSecond() + offset.getTotalSeconds(); // overflow caught later
 int secsOfDay = Math.floorMod(localSecond, SECONDS_PER_DAY);
 LocalTime time = LocalTime.ofNanoOfDay(secsOfDay * NANOS_PER_SECOND + instant.getNano());
 return new OffsetTime(time, offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code OffsetTime} from a temporal object.
 * <p>
 * This obtains an offset 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 OffsetTime}.
 * <p>
 * The conversion extracts and combines the {@code ZoneOffset} and the
 * {@code LocalTime} from the temporal object.
 * 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 OffsetTime::from}.
 *
 * @param temporal the temporal object to convert, not null
 * @return the offset time, not null
 * @throws DateTimeException if unable to convert to an {@code OffsetTime}
 */
 public static OffsetTime from(TemporalAccessor temporal) {
 if (temporal instanceof OffsetTime) {
 return (OffsetTime) temporal;
 }
 try {
 LocalTime time = LocalTime.from(temporal);
 ZoneOffset offset = ZoneOffset.from(temporal);
 return new OffsetTime(time, offset);
 } catch (DateTimeException ex) {
 throw new DateTimeException("Unable to obtain OffsetTime from TemporalAccessor: " +
 temporal + " of type " + temporal.getClass().getName(), ex);
 }
 }

 //-----------------------------------------------------------------------
 /**
 * Obtains an instance of {@code OffsetTime} from a text string such as {@code 10:15:30+01:00}.
 * <p>
 * The string must represent a valid time and is parsed using
 * {@link java.time.format.DateTimeFormatter#ISO_OFFSET_TIME}.
 *
 * @param text the text to parse such as "10:15:30+01:00", not null
 * @return the parsed local time, not null
 * @throws DateTimeParseException if the text cannot be parsed
 */
 public static OffsetTime parse(CharSequence text) {
 return parse(text, DateTimeFormatter.ISO_OFFSET_TIME);
 }

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

 //-----------------------------------------------------------------------
 /**
 * Constructor.
 *
 * @param time the local time, not null
 * @param offset the zone offset, not null
 */
 private OffsetTime(LocalTime time, ZoneOffset offset) {
 this.time = Objects.requireNonNull(time, "time");
 this.offset = Objects.requireNonNull(offset, "offset");
 }

 /**
 * Returns a new time based on this one, returning {@code this} where possible.
 *
 * @param time the time to create with, not null
 * @param offset the zone offset to create with, not null
 */
 private OffsetTime with(LocalTime time, ZoneOffset offset) {
 if (this.time == time && this.offset.equals(offset)) {
 return this;
 }
 return new OffsetTime(time, offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Checks if the specified field is supported.
 * <p>
 * This checks if this 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 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 time, false if not
 */
 @Override
 public boolean isSupported(TemporalField field) {
 if (field instanceof ChronoField) {
 return field.isTimeBased() || field == OFFSET_SECONDS;
 }
 return 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 offset-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}
 * </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) {
 if (unit instanceof ChronoUnit) {
 return unit.isTimeBased();
 }
 return unit != null && unit.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 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 == OFFSET_SECONDS) {
 return field.range();
 }
 return time.range(field);
 }
 return field.rangeRefinedBy(this);
 }

 /**
 * Gets the value of the specified field from this time as an {@code int}.
 * <p>
 * This queries this 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 time, except {@code NANO_OF_DAY} and {@code MICRO_OF_DAY}
 * which are too large to fit in an {@code int} and throw an {@code UnsupportedTemporalTypeException}.
 * 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
 public int get(TemporalField field) {
 return Temporal.super.get(field);
 }

 /**
 * Gets the value of the specified field from this time as a {@code long}.
 * <p>
 * This queries this 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 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) {
 if (field == OFFSET_SECONDS) {
 return offset.getTotalSeconds();
 }
 return time.getLong(field);
 }
 return field.getFrom(this);
 }

 //-----------------------------------------------------------------------
 /**
 * Gets the zone offset, such as '+01:00'.
 * <p>
 * This is the offset of the local time from UTC/Greenwich.
 *
 * @return the zone offset, not null
 */
 public ZoneOffset getOffset() {
 return offset;
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
 * that the result has the same local time.
 * <p>
 * This method returns an object with the same {@code LocalTime} and the specified {@code ZoneOffset}.
 * No calculation is needed or performed.
 * For example, if this time represents {@code 10:30+02:00} and the offset specified is
 * {@code +03:00}, then this method will return {@code 10:30+03:00}.
 * <p>
 * To take into account the difference between the offsets, and adjust the time fields,
 * use {@link #withOffsetSameInstant}.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param offset the zone offset to change to, not null
 * @return an {@code OffsetTime} based on this time with the requested offset, not null
 */
 public OffsetTime withOffsetSameLocal(ZoneOffset offset) {
 return offset != null && offset.equals(this.offset) ? this : new OffsetTime(time, offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified offset ensuring
 * that the result is at the same instant on an implied day.
 * <p>
 * This method returns an object with the specified {@code ZoneOffset} and a {@code LocalTime}
 * adjusted by the difference between the two offsets.
 * This will result in the old and new objects representing the same instant on an implied day.
 * This is useful for finding the local time in a different offset.
 * For example, if this time represents {@code 10:30+02:00} and the offset specified is
 * {@code +03:00}, then this method will return {@code 11:30+03:00}.
 * <p>
 * To change the offset without adjusting the local time use {@link #withOffsetSameLocal}.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param offset the zone offset to change to, not null
 * @return an {@code OffsetTime} based on this time with the requested offset, not null
 */
 public OffsetTime withOffsetSameInstant(ZoneOffset offset) {
 if (offset.equals(this.offset)) {
 return this;
 }
 int difference = offset.getTotalSeconds() - this.offset.getTotalSeconds();
 LocalTime adjusted = time.plusSeconds(difference);
 return new OffsetTime(adjusted, offset);
 }

 //-----------------------------------------------------------------------
 /**
 * 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
 */
 public LocalTime toLocalTime() {
 return time;
 }

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

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

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

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

 //-----------------------------------------------------------------------
 /**
 * Returns an adjusted copy of this time.
 * <p>
 * This returns an {@code OffsetTime}, based on this one, with the 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 hour field.
 * A more complex adjuster might set the time to the last hour of the day.
 * <p>
 * The classes {@link LocalTime} and {@link ZoneOffset} implement {@code TemporalAdjuster},
 * thus this method can be used to change the time or offset:
 * <pre>
 * result = offsetTime.with(time);
 * result = offsetTime.with(offset);
 * </pre>
 * <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 an {@code OffsetTime} 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 OffsetTime with(TemporalAdjuster adjuster) {
 // optimizations
 if (adjuster instanceof LocalTime) {
 return with((LocalTime) adjuster, offset);
 } else if (adjuster instanceof ZoneOffset) {
 return with(time, (ZoneOffset) adjuster);
 } else if (adjuster instanceof OffsetTime) {
 return (OffsetTime) adjuster;
 }
 return (OffsetTime) adjuster.adjustInto(this);
 }

 /**
 * Returns a copy of this time with the specified field set to a new value.
 * <p>
 * This returns an {@code OffsetTime}, based on this one, with the value
 * for the specified field changed.
 * This can be used to change any supported field, such as the hour, minute or second.
 * 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>
 * If the field is a {@link ChronoField} then the adjustment is implemented here.
 * <p>
 * The {@code OFFSET_SECONDS} field will return a time with the specified offset.
 * The local time is unaltered. 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 LocalTime#with(TemporalField, long)} LocalTime}.
 * In this case, the offset is not part of the calculation and will be unchanged.
 * <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 an {@code OffsetTime} 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 OffsetTime with(TemporalField field, long newValue) {
 if (field instanceof ChronoField) {
 if (field == OFFSET_SECONDS) {
 ChronoField f = (ChronoField) field;
 return with(time, ZoneOffset.ofTotalSeconds(f.checkValidIntValue(newValue)));
 }
 return with(time.with(field, newValue), offset);
 }
 return field.adjustInto(this, newValue);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a copy of this {@code OffsetTime} with the hour-of-day altered.
 * <p>
 * The offset does not affect the calculation and will be the same in the result.
 * <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 an {@code OffsetTime} based on this time with the requested hour, not null
 * @throws DateTimeException if the hour value is invalid
 */
 public OffsetTime withHour(int hour) {
 return with(time.withHour(hour), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the minute-of-hour altered.
 * <p>
 * The offset does not affect the calculation and will be the same in the result.
 * <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 an {@code OffsetTime} based on this time with the requested minute, not null
 * @throws DateTimeException if the minute value is invalid
 */
 public OffsetTime withMinute(int minute) {
 return with(time.withMinute(minute), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the second-of-minute altered.
 * <p>
 * The offset does not affect the calculation and will be the same in the result.
 * <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 an {@code OffsetTime} based on this time with the requested second, not null
 * @throws DateTimeException if the second value is invalid
 */
 public OffsetTime withSecond(int second) {
 return with(time.withSecond(second), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the nano-of-second altered.
 * <p>
 * The offset does not affect the calculation and will be the same in the result.
 * <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 an {@code OffsetTime} based on this time with the requested nanosecond, not null
 * @throws DateTimeException if the nanos value is invalid
 */
 public OffsetTime withNano(int nanoOfSecond) {
 return with(time.withNano(nanoOfSecond), offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a copy of this {@code OffsetTime} with the time truncated.
 * <p>
 * Truncation returns a copy of the original 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>
 * The offset does not affect the calculation and will be the same in the result.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param unit the unit to truncate to, not null
 * @return an {@code OffsetTime} based on this time with the time truncated, not null
 * @throws DateTimeException if unable to truncate
 * @throws UnsupportedTemporalTypeException if the unit is not supported
 */
 public OffsetTime truncatedTo(TemporalUnit unit) {
 return with(time.truncatedTo(unit), offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a copy of this time with the specified amount added.
 * <p>
 * This returns an {@code OffsetTime}, based on this one, with the specified amount added.
 * The amount is typically {@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 an {@code OffsetTime} based on this time with the addition made, not null
 * @throws DateTimeException if the addition cannot be made
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public OffsetTime plus(TemporalAmount amountToAdd) {
 return (OffsetTime) amountToAdd.addTo(this);
 }

 /**
 * Returns a copy of this time with the specified amount added.
 * <p>
 * This returns an {@code OffsetTime}, 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 by
 * {@link LocalTime#plus(long, TemporalUnit)}.
 * The offset is not part of the calculation and will be unchanged in the result.
 * <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 an {@code OffsetTime} based on this 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 OffsetTime plus(long amountToAdd, TemporalUnit unit) {
 if (unit instanceof ChronoUnit) {
 return with(time.plus(amountToAdd, unit), offset);
 }
 return unit.addTo(this, amountToAdd);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of hours added.
 * <p>
 * This adds the specified number of hours to this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param hours the hours to add, may be negative
 * @return an {@code OffsetTime} based on this time with the hours added, not null
 */
 public OffsetTime plusHours(long hours) {
 return with(time.plusHours(hours), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of minutes added.
 * <p>
 * This adds the specified number of minutes to this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param minutes the minutes to add, may be negative
 * @return an {@code OffsetTime} based on this time with the minutes added, not null
 */
 public OffsetTime plusMinutes(long minutes) {
 return with(time.plusMinutes(minutes), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of seconds added.
 * <p>
 * This adds the specified number of seconds to this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param seconds the seconds to add, may be negative
 * @return an {@code OffsetTime} based on this time with the seconds added, not null
 */
 public OffsetTime plusSeconds(long seconds) {
 return with(time.plusSeconds(seconds), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds added.
 * <p>
 * This adds the specified number of nanoseconds to this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param nanos the nanos to add, may be negative
 * @return an {@code OffsetTime} based on this time with the nanoseconds added, not null
 */
 public OffsetTime plusNanos(long nanos) {
 return with(time.plusNanos(nanos), offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Returns a copy of this time with the specified amount subtracted.
 * <p>
 * This returns an {@code OffsetTime}, based on this one, with the specified amount subtracted.
 * The amount is typically {@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 an {@code OffsetTime} based on this time with the subtraction made, not null
 * @throws DateTimeException if the subtraction cannot be made
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public OffsetTime minus(TemporalAmount amountToSubtract) {
 return (OffsetTime) amountToSubtract.subtractFrom(this);
 }

 /**
 * Returns a copy of this time with the specified amount subtracted.
 * <p>
 * This returns an {@code OffsetTime}, 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>
 * 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 an {@code OffsetTime} based on this 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 OffsetTime 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 OffsetTime} with the specified number of hours subtracted.
 * <p>
 * This subtracts the specified number of hours from this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param hours the hours to subtract, may be negative
 * @return an {@code OffsetTime} based on this time with the hours subtracted, not null
 */
 public OffsetTime minusHours(long hours) {
 return with(time.minusHours(hours), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of minutes subtracted.
 * <p>
 * This subtracts the specified number of minutes from this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param minutes the minutes to subtract, may be negative
 * @return an {@code OffsetTime} based on this time with the minutes subtracted, not null
 */
 public OffsetTime minusMinutes(long minutes) {
 return with(time.minusMinutes(minutes), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of seconds subtracted.
 * <p>
 * This subtracts the specified number of seconds from this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param seconds the seconds to subtract, may be negative
 * @return an {@code OffsetTime} based on this time with the seconds subtracted, not null
 */
 public OffsetTime minusSeconds(long seconds) {
 return with(time.minusSeconds(seconds), offset);
 }

 /**
 * Returns a copy of this {@code OffsetTime} with the specified number of nanoseconds subtracted.
 * <p>
 * This subtracts the specified number of nanoseconds from this time, returning a new time.
 * The calculation wraps around midnight.
 * <p>
 * This instance is immutable and unaffected by this method call.
 *
 * @param nanos the nanos to subtract, may be negative
 * @return an {@code OffsetTime} based on this time with the nanoseconds subtracted, not null
 */
 public OffsetTime minusNanos(long nanos) {
 return with(time.minusNanos(nanos), offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Queries this time using the specified query.
 * <p>
 * This queries this 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
 public <R> R query(TemporalQuery<R> query) {
 if (query == TemporalQueries.offset() || query == TemporalQueries.zone()) {
 return (R) offset;
 } else if (query == TemporalQueries.zoneId() | query == TemporalQueries.chronology() || query == TemporalQueries.localDate()) {
 return null;
 } else if (query == TemporalQueries.localTime()) {
 return (R) time;
 } else if (query == TemporalQueries.precision()) {
 return (R) NANOS;
 }
 // inline TemporalAccessor.super.query(query) as an optimization
 // non-JDK classes are not permitted to make this optimization
 return query.queryFrom(this);
 }

 /**
 * Adjusts the specified temporal object to have the same offset and time
 * as this object.
 * <p>
 * This returns a temporal object of the same observable type as the input
 * with the offset and time changed to be the same as this.
 * <p>
 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
 * twice, passing {@link ChronoField#NANO_OF_DAY} and
 * {@link ChronoField#OFFSET_SECONDS} as the fields.
 * <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 = thisOffsetTime.adjustInto(temporal);
 * temporal = temporal.with(thisOffsetTime);
 * </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(NANO_OF_DAY, time.toNanoOfDay())
 .with(OFFSET_SECONDS, offset.getTotalSeconds());
 }

 /**
 * Calculates the amount of time until another time in terms of the specified unit.
 * <p>
 * This calculates the amount of time between two {@code OffsetTime}
 * objects in terms of a single {@code TemporalUnit}.
 * The start and end points are {@code this} and the specified time.
 * The result will be negative if the end is before the start.
 * For example, the amount in hours between two times can be calculated
 * using {@code startTime.until(endTime, HOURS)}.
 * <p>
 * The {@code Temporal} passed to this method is converted to a
 * {@code OffsetTime} using {@link #from(TemporalAccessor)}.
 * If the offset differs between the two times, then the specified
 * end time is normalized to have the same offset as this time.
 * <p>
 * The calculation returns a whole number, representing the number of
 * complete units between the two times.
 * For example, the amount in hours between 11:30Z and 13:29Z will only
 * be one hour as it is one minute short of two hours.
 * <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, MINUTES);
 * amount = MINUTES.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} are supported.
 * Other {@code ChronoUnit} values will throw an exception.
 * <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 time, exclusive, which is converted to an {@code OffsetTime}, not null
 * @param unit the unit to measure the amount in, not null
 * @return the amount of time between this time and the end time
 * @throws DateTimeException if the amount cannot be calculated, or the end
 * temporal cannot be converted to an {@code OffsetTime}
 * @throws UnsupportedTemporalTypeException if the unit is not supported
 * @throws ArithmeticException if numeric overflow occurs
 */
 @Override
 public long until(Temporal endExclusive, TemporalUnit unit) {
 OffsetTime end = OffsetTime.from(endExclusive);
 if (unit instanceof ChronoUnit) {
 long nanosUntil = end.toEpochNano() - toEpochNano(); // no overflow
 switch ((ChronoUnit) unit) {
 case NANOS: return nanosUntil;
 case MICROS: return nanosUntil / 1000;
 case MILLIS: return nanosUntil / 1000_000;
 case SECONDS: return nanosUntil / NANOS_PER_SECOND;
 case MINUTES: return nanosUntil / NANOS_PER_MINUTE;
 case HOURS: return nanosUntil / NANOS_PER_HOUR;
 case HALF_DAYS: return nanosUntil / (12 * NANOS_PER_HOUR);
 }
 throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
 }
 return unit.between(this, end);
 }

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

 //-----------------------------------------------------------------------
 /**
 * Combines this time with a date to create an {@code OffsetDateTime}.
 * <p>
 * This returns an {@code OffsetDateTime} formed from this time and the specified date.
 * All possible combinations of date and time are valid.
 *
 * @param date the date to combine with, not null
 * @return the offset date-time formed from this time and the specified date, not null
 */
 public OffsetDateTime atDate(LocalDate date) {
 return OffsetDateTime.of(date, time, offset);
 }

 //-----------------------------------------------------------------------
 /**
 * Converts this time to epoch nanos based on 1970年01月01日Z.
 *
 * @return the epoch nanos value
 */
 private long toEpochNano() {
 long nod = time.toNanoOfDay();
 long offsetNanos = offset.getTotalSeconds() * NANOS_PER_SECOND;
 return nod - offsetNanos;
 }

 /**
 * Converts this {@code OffsetTime} to the number of seconds since the epoch
 * of 1970年01月01日T00:00:00Z.
 * <p>
 * This combines this offset time with the specified date to calculate the
 * epoch-second value, which is the number of elapsed seconds from
 * 1970年01月01日T00:00:00Z.
 * Instants on the time-line after the epoch are positive, earlier
 * are negative.
 *
 * @param date the localdate, not null
 * @return the number of seconds since the epoch of 1970年01月01日T00:00:00Z, may be negative
 * @since 9
 */
 public long toEpochSecond(LocalDate date) {
 Objects.requireNonNull(date, "date");
 long epochDay = date.toEpochDay();
 long secs = epochDay * 86400 + time.toSecondOfDay();
 secs -= offset.getTotalSeconds();
 return secs;
 }

 //-----------------------------------------------------------------------
 /**
 * Compares this {@code OffsetTime} to another time.
 * <p>
 * The comparison is based first on the UTC equivalent instant, then on the local time.
 * It is "consistent with equals", as defined by {@link Comparable}.
 * <p>
 * For example, the following is the comparator order:
 * <ol>
 * <li>{@code 10:30+01:00}</li>
 * <li>{@code 11:00+01:00}</li>
 * <li>{@code 12:00+02:00}</li>
 * <li>{@code 11:30+01:00}</li>
 * <li>{@code 12:00+01:00}</li>
 * <li>{@code 12:30+01:00}</li>
 * </ol>
 * Values #2 and #3 represent the same instant on the time-line.
 * When two values represent the same instant, the local time is compared
 * to distinguish them. This step is needed to make the ordering
 * consistent with {@code equals()}.
 * <p>
 * To compare the underlying local time of two {@code TemporalAccessor} instances,
 * use {@link ChronoField#NANO_OF_DAY} as a comparator.
 *
 * @param other the other time to compare to, not null
 * @return the comparator value, negative if less, positive if greater
 */
 @Override
 public int compareTo(OffsetTime other) {
 if (offset.equals(other.offset)) {
 return time.compareTo(other.time);
 }
 int compare = Long.compare(toEpochNano(), other.toEpochNano());
 if (compare == 0) {
 compare = time.compareTo(other.time);
 }
 return compare;
 }

 //-----------------------------------------------------------------------
 /**
 * Checks if the instant of this {@code OffsetTime} is after that of the
 * specified time applying both times to a common date.
 * <p>
 * This method differs from the comparison in {@link #compareTo} in that it
 * only compares the instant of the time. This is equivalent to converting both
 * times to an instant using the same date and comparing the instants.
 *
 * @param other the other time to compare to, not null
 * @return true if this is after the instant of the specified time
 */
 public boolean isAfter(OffsetTime other) {
 return toEpochNano() > other.toEpochNano();
 }

 /**
 * Checks if the instant of this {@code OffsetTime} is before that of the
 * specified time applying both times to a common date.
 * <p>
 * This method differs from the comparison in {@link #compareTo} in that it
 * only compares the instant of the time. This is equivalent to converting both
 * times to an instant using the same date and comparing the instants.
 *
 * @param other the other time to compare to, not null
 * @return true if this is before the instant of the specified time
 */
 public boolean isBefore(OffsetTime other) {
 return toEpochNano() < other.toEpochNano();
 }

 /**
 * Checks if the instant of this {@code OffsetTime} is equal to that of the
 * specified time applying both times to a common date.
 * <p>
 * This method differs from the comparison in {@link #compareTo} and {@link #equals}
 * in that it only compares the instant of the time. This is equivalent to converting both
 * times to an instant using the same date and comparing the instants.
 *
 * @param other the other time to compare to, not null
 * @return true if this is equal to the instant of the specified time
 */
 public boolean isEqual(OffsetTime other) {
 return toEpochNano() == other.toEpochNano();
 }

 //-----------------------------------------------------------------------
 /**
 * Checks if this time is equal to another time.
 * <p>
 * The comparison is based on the local-time and the offset.
 * To compare for the same instant on the time-line, use {@link #isEqual(OffsetTime)}.
 * <p>
 * Only objects of type {@code OffsetTime} are compared, other types return false.
 * To compare the underlying local time of two {@code TemporalAccessor} instances,
 * use {@link ChronoField#NANO_OF_DAY} as a comparator.
 *
 * @param obj the object to check, null returns false
 * @return true if this is equal to the other time
 */
 @Override
 public boolean equals(Object obj) {
 if (this == obj) {
 return true;
 }
 if (obj instanceof OffsetTime) {
 OffsetTime other = (OffsetTime) obj;
 return time.equals(other.time) && offset.equals(other.offset);
 }
 return false;
 }

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

 //-----------------------------------------------------------------------
 /**
 * Outputs this time as a {@code String}, such as {@code 10:15:30+01:00}.
 * <p>
 * The output will be one of the following ISO-8601 formats:
 * <ul>
 * <li>{@code HH:mmXXXXX}</li>
 * <li>{@code HH:mm:ssXXXXX}</li>
 * <li>{@code HH:mm:ss.SSSXXXXX}</li>
 * <li>{@code HH:mm:ss.SSSSSSXXXXX}</li>
 * <li>{@code HH:mm:ss.SSSSSSSSSXXXXX}</li>
 * </ul>
 * The format used will be the shortest that outputs the full value of
 * the time where the omitted parts are implied to be zero.
 *
 * @return a string representation of this time, not null
 */
 @Override
 public String toString() {
 return time.toString() + offset.toString();
 }

 //-----------------------------------------------------------------------
 /**
 * Writes the object using a
 * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
 * @serialData
 * <pre>
 * out.writeByte(9); // identifies an OffsetTime
 * // the <a href="../../serialized-form.html#java.time.LocalTime">time</a> excluding the one byte header
 * // the <a href="../../serialized-form.html#java.time.ZoneOffset">offset</a> excluding the one byte header
 * </pre>
 *
 * @return the instance of {@code Ser}, not null
 */
 private Object writeReplace() {
 return new Ser(Ser.OFFSET_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(ObjectOutput out) throws IOException {
 time.writeExternal(out);
 offset.writeExternal(out);
 }

 static OffsetTime readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
 LocalTime time = LocalTime.readExternal(in);
 ZoneOffset offset = ZoneOffset.readExternal(in);
 return OffsetTime.of(time, offset);
 }

}