/*
 * Copyright (c) 2007-2013, 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 org.threeten.bp;

import static org.threeten.bp.temporal.ChronoField.EPOCH_DAY;
import static org.threeten.bp.temporal.ChronoField.INSTANT_SECONDS;
import static org.threeten.bp.temporal.ChronoField.NANO_OF_DAY;
import static org.threeten.bp.temporal.ChronoField.OFFSET_SECONDS;
import static org.threeten.bp.temporal.ChronoUnit.NANOS;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectStreamException;
import java.io.Serializable;
import java.util.Comparator;
import java.util.Objects;

import org.threeten.bp.format.DateTimeFormatter;
import org.threeten.bp.format.DateTimeFormatters;
import org.threeten.bp.format.DateTimeParseException;
import org.threeten.bp.jdk8.DefaultInterfaceTemporal;
import org.threeten.bp.temporal.ChronoField;
import org.threeten.bp.temporal.ChronoUnit;
import org.threeten.bp.temporal.Temporal;
import org.threeten.bp.temporal.TemporalAccessor;
import org.threeten.bp.temporal.TemporalAdder;
import org.threeten.bp.temporal.TemporalAdjuster;
import org.threeten.bp.temporal.TemporalAdjusters;
import org.threeten.bp.temporal.TemporalField;
import org.threeten.bp.temporal.TemporalQueries;
import org.threeten.bp.temporal.TemporalQuery;
import org.threeten.bp.temporal.TemporalSubtractor;
import org.threeten.bp.temporal.TemporalUnit;
import org.threeten.bp.temporal.ValueRange;
import org.threeten.bp.zone.ZoneRules;

/**
 * A date-time with an offset from UTC/Greenwich in the ISO-8601 calendar system,
 * such as {@code 2007-12-03T10:15:30+01:00}.
 * <p>
 * {@code OffsetDateTime} is an immutable representation of a date-time with an offset.
 * This class stores all date and time fields, to a precision of nanoseconds,
 * as well as the offset from UTC/Greenwich. For example, the value
 * "2nd October 2007 at 13:45.30.123456789 +02:00" can be stored in an {@code OffsetDateTime}.
 * <p>
 * {@code OffsetDateTime}, {@link ZonedDateTime} and {@link Instant} all store an instant
 * on the time-line to nanosecond precision.
 * {@code Instant} is the simplest, simply representing the instant.
 * {@code OffsetDateTime} adds to the instant the offset from UTC/Greenwich, which allows
 * the local date-time to be obtained.
 * {@code ZonedDateTime} adds full time-zone rules.
 * <p>
 * It is intended that {@code ZonedDateTime} or {@code Instant} is used to model data
 * in simpler applications. This class may be used when modeling date-time concepts in
 * more detail, or when communicating to a database or in a network protocol.
 *
 * <h3>Specification for implementors</h3>
 * This class is immutable and thread-safe.
 */
public final class OffsetDateTime
        extends DefaultInterfaceTemporal
        implements Temporal, TemporalAdjuster, Comparable<OffsetDateTime>, Serializable {

    /**
     * The minimum supported {@code OffsetDateTime}, '-999999999-01-01T00:00:00+18:00'.
     * This is the local date-time of midnight at the start of the minimum date
     * in the maximum offset (larger offsets are earlier on the time-line).
     * This combines {@link LocalDateTime#MIN} and {@link ZoneOffset#MAX}.
     * This could be used by an application as a "far past" date-time.
     */
    public static final OffsetDateTime MIN = LocalDateTime.MIN.atOffset(ZoneOffset.MAX);
    /**
     * The maximum supported {@code OffsetDateTime}, '+999999999-12-31T23:59:59.999999999-18:00'.
     * This is the local date-time just before midnight at the end of the maximum date
     * in the minimum offset (larger negative offsets are later on the time-line).
     * This combines {@link LocalDateTime#MAX} and {@link ZoneOffset#MIN}.
     * This could be used by an application as a "far future" date-time.
     */
    public static final OffsetDateTime MAX = LocalDateTime.MAX.atOffset(ZoneOffset.MIN);

    /**
     * Comparator for two {@code OffsetDateTime} instances based solely on the instant.
     * <p>
     * This method differs from the comparison in {@link #compareTo} in that it
     * only compares the underlying instant.
     *
     * @see #isAfter
     * @see #isBefore
     * @see #isEqual
     */
    public static final Comparator<OffsetDateTime> INSTANT_COMPARATOR = new Comparator<OffsetDateTime>() {
        @Override
        public int compare(OffsetDateTime datetime1, OffsetDateTime datetime2) {
            int cmp = Long.compare(datetime1.toEpochSecond(), datetime2.toEpochSecond());
            if (cmp == 0) {
                cmp = Long.compare(datetime1.getTime().toNanoOfDay(), datetime2.getTime().toNanoOfDay());
            }
            return cmp;
        }
    };

    /**
     * Serialization version.
     */
    private static final long serialVersionUID = 2287754244819255394L;

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

    //-----------------------------------------------------------------------
    /**
     * 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 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 date-time using the system clock, not null
     */
    public static OffsetDateTime 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 OffsetDateTime 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 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 date-time, not null
     */
    public static OffsetDateTime 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 OffsetDateTime} from a date, time and offset.
     * <p>
     * This creates an offset date-time with the specified local date, time and offset.
     *
     * @param date  the local date, not null
     * @param time  the local time, not null
     * @param offset  the zone offset, not null
     * @return the offset date-time, not null
     */
    public static OffsetDateTime of(LocalDate date, LocalTime time, ZoneOffset offset) {
        LocalDateTime dt = LocalDateTime.of(date, time);
        return new OffsetDateTime(dt, offset);
    }

    /**
     * Obtains an instance of {@code OffsetDateTime} from a date-time and offset.
     * <p>
     * This creates an offset date-time with the specified local date-time and offset.
     *
     * @param dateTime  the local date-time, not null
     * @param offset  the zone offset, not null
     * @return the offset date-time, not null
     */
    public static OffsetDateTime of(LocalDateTime dateTime, ZoneOffset offset) {
        return new OffsetDateTime(dateTime, offset);
    }

    /**
     * Obtains an instance of {@code OffsetDateTime} from a {@code ZonedDateTime}.
     * <p>
     * This creates an offset date-time with the same local date-time and offset as
     * the zoned date-time. The result will have the same instant as the input.
     *
     * @param zonedDateTime  the zoned date-time to convert from, not null
     * @return the offset date-time, not null
     * @throws DateTimeException if the result exceeds the supported range
     */
    public static OffsetDateTime of(ZonedDateTime zonedDateTime) {
        Objects.requireNonNull(zonedDateTime, "zonedDateTime");
        return new OffsetDateTime(zonedDateTime.getDateTime(), zonedDateTime.getOffset());
    }

    //-----------------------------------------------------------------------
    /**
     * Obtains an instance of {@code OffsetDateTime} from an {@code Instant} and zone ID.
     * <p>
     * This creates an offset date-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.
     *
     * @param instant  the instant to create the date-time from, not null
     * @param zone  the time-zone, which may be an offset, not null
     * @return the offset date-time, not null
     * @throws DateTimeException if the result exceeds the supported range
     */
    public static OffsetDateTime ofInstant(Instant instant, ZoneId zone) {
        Objects.requireNonNull(instant, "instant");
        Objects.requireNonNull(zone, "zone");
        ZoneRules rules = zone.getRules();
        ZoneOffset offset = rules.getOffset(instant);
        LocalDateTime ldt = LocalDateTime.ofEpochSecond(instant.getEpochSecond(), instant.getNano(), offset);
        return new OffsetDateTime(ldt, offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Obtains an instance of {@code OffsetDateTime} from a temporal object.
     * <p>
     * A {@code TemporalAccessor} represents some form of date and time information.
     * This factory converts the arbitrary temporal object to an instance of {@code OffsetDateTime}.
     * <p>
     * The conversion extracts and combines {@code LocalDateTime} and {@code ZoneOffset}.
     * If that fails it will try to extract and combine {@code Instant} and {@code ZoneOffset}.
     * <p>
     * This method matches the signature of the functional interface {@link TemporalQuery}
     * allowing it to be used in queries via method reference, {@code OffsetDateTime::from}.
     *
     * @param temporal  the temporal object to convert, not null
     * @return the offset date-time, not null
     * @throws DateTimeException if unable to convert to an {@code OffsetDateTime}
     */
    public static OffsetDateTime from(TemporalAccessor temporal) {
        if (temporal instanceof OffsetDateTime) {
            return (OffsetDateTime) temporal;
        }
        ZoneOffset offset = ZoneOffset.from(temporal);
        try {
            try {
                LocalDateTime ldt = LocalDateTime.from(temporal);
                return OffsetDateTime.of(ldt, offset);
            } catch (DateTimeException ignore) {
                Instant instant = Instant.from(temporal);
                return OffsetDateTime.ofInstant(instant, offset);
            }
        } catch (DateTimeException ex) {
            throw new DateTimeException("Unable to obtain OffsetDateTime from TemporalAccessor: " + temporal.getClass(), ex);
        }
    }

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

    /**
     * Obtains an instance of {@code OffsetDateTime} 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 offset date-time, not null
     * @throws DateTimeParseException if the text cannot be parsed
     */
    public static OffsetDateTime parse(CharSequence text, DateTimeFormatter formatter) {
        Objects.requireNonNull(formatter, "formatter");
        return formatter.parse(text, OffsetDateTime.class);
    }

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

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

    //-----------------------------------------------------------------------
    /**
     * 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} 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 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 EPOCH_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.doIsSupported(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.doIsSupported(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 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 a {@code DateTimeException}.
     * <p>
     * If the field is not a {@code ChronoField}, then the result of this method
     * is obtained by invoking {@code TemporalField.doRange(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
     */
    @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.doRange(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 for 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 EPOCH_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 a {@code DateTimeException}.
     * <p>
     * If the field is not a {@code ChronoField}, then the result of this method
     * is obtained by invoking {@code TemporalField.doGet(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 ArithmeticException if numeric overflow occurs
     */
    @Override
    public int get(TemporalField field) {
        if (field instanceof ChronoField) {
            switch ((ChronoField) field) {
                case INSTANT_SECONDS: throw new DateTimeException("Field too large for an int: " + field);
                case OFFSET_SECONDS: return getOffset().getTotalSeconds();
            }
            return dateTime.get(field);
        }
        return 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 for 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 a {@code DateTimeException}.
     * <p>
     * If the field is not a {@code ChronoField}, then the result of this method
     * is obtained by invoking {@code TemporalField.doGet(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 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.doGet(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
     */
    public ZoneOffset getOffset() {
        return offset;
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified offset ensuring
     * that the result has the same local date-time.
     * <p>
     * This method returns an object with the same {@code LocalDateTime} and the specified {@code ZoneOffset}.
     * No calculation is needed or performed.
     * For example, if this time represents {@code 2007-12-03T10:30+02:00} and the offset specified is
     * {@code +03:00}, then this method will return {@code 2007-12-03T10:30+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 OffsetDateTime} based on this date-time with the requested offset, not null
     */
    public OffsetDateTime withOffsetSameLocal(ZoneOffset offset) {
        return with(dateTime, offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified offset ensuring
     * that the result is at the same instant.
     * <p>
     * This method returns an object with the specified {@code ZoneOffset} and a {@code LocalDateTime}
     * adjusted by the difference between the two offsets.
     * This will result in the old and new objects representing the same instant.
     * This is useful for finding the local time in a different offset.
     * For example, if this time represents {@code 2007-12-03T10:30+02:00} and the offset specified is
     * {@code +03:00}, then this method will return {@code 2007-12-03T11:30+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 OffsetDateTime} based on this date-time with the requested offset, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime withOffsetSameInstant(ZoneOffset offset) {
        if (offset.equals(this.offset)) {
            return this;
        }
        int difference = offset.getTotalSeconds() - this.offset.getTotalSeconds();
        LocalDateTime adjusted = dateTime.plusSeconds(difference);
        return new OffsetDateTime(adjusted, offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Gets the {@code LocalDateTime} part of this offset 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
     */
    public LocalDateTime getDateTime() {
        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
     */
    public LocalDate getDate() {
        return dateTime.getDate();
    }

    /**
     * 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
     */
    public LocalTime getTime() {
        return dateTime.getTime();
    }

    /**
     * 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 new {@code OffsetDateTime}, 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 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 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 org.threeten.bp.Month.*;
     *  import static org.threeten.bp.temporal.Adjusters.*;
     *
     *  result = offsetDateTime.with(JULY).with(lastDayOfMonth());
     * </pre>
     * <p>
     * The classes {@link LocalDate}, {@link LocalTime} and {@link ZoneOffset} implement
     * {@code TemporalAdjuster}, thus this method can be used to change the date, time or offset:
     * <pre>
     *  result = offsetDateTime.with(date);
     *  result = offsetDateTime.with(time);
     *  result = offsetDateTime.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 OffsetDateTime} 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 OffsetDateTime with(TemporalAdjuster adjuster) {
        // optimizations
        if (adjuster instanceof LocalDate || adjuster instanceof LocalTime || adjuster instanceof LocalDateTime) {
            return with(dateTime.with(adjuster), offset);
        } else if (adjuster instanceof Instant) {
            return ofInstant((Instant) adjuster, offset);
        } else if (adjuster instanceof ZoneOffset) {
            return with(dateTime, (ZoneOffset) adjuster);
        } else if (adjuster instanceof OffsetDateTime) {
            return (OffsetDateTime) adjuster;
        }
        return (OffsetDateTime) adjuster.adjustInto(this);
    }

    /**
     * Returns a copy of this date-time with the specified field set to a new value.
     * <p>
     * This returns a new {@code OffsetDateTime}, 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 offset and nano-of-second are unchanged.
     * If the new instant value is outside the valid range then a {@code DateTimeException} will be thrown.
     * <p>
     * The {@code OFFSET_SECONDS} field will return a date-time with the specified offset.
     * The local date-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 LocalDateTime#with(TemporalField, long) LocalDateTime}.
     * In this case, the offset is not part of the calculation and will be unchanged.
     * <p>
     * All other {@code ChronoField} instances will throw a {@code DateTimeException}.
     * <p>
     * If the field is not a {@code ChronoField}, then the result of this method
     * is obtained by invoking {@code TemporalField.doWith(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 OffsetDateTime} based on {@code this} with the specified field set, not null
     * @throws DateTimeException if the field cannot be set
     * @throws ArithmeticException if numeric overflow occurs
     */
    @Override
    public OffsetDateTime with(TemporalField field, long newValue) {
        if (field instanceof ChronoField) {
            ChronoField f = (ChronoField) field;
            switch (f) {
                case INSTANT_SECONDS: return ofInstant(Instant.ofEpochSecond(newValue, getNano()), offset);
                case OFFSET_SECONDS: {
                    return with(dateTime, ZoneOffset.ofTotalSeconds(f.checkValidIntValue(newValue)));
                }
            }
            return with(dateTime.with(field, newValue), offset);
        }
        return field.doWith(this, newValue);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this {@code OffsetDateTime} with the year altered.
     * The offset does not affect the calculation and will be the same in the result.
     * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
     * <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 an {@code OffsetDateTime} based on this date-time with the requested year, not null
     * @throws DateTimeException if the year value is invalid
     */
    public OffsetDateTime withYear(int year) {
        return with(dateTime.withYear(year), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the month-of-year altered.
     * The offset does not affect the calculation and will be the same in the result.
     * If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
     * <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 an {@code OffsetDateTime} based on this date-time with the requested month, not null
     * @throws DateTimeException if the month-of-year value is invalid
     */
    public OffsetDateTime withMonth(int month) {
        return with(dateTime.withMonth(month), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the day-of-month altered.
     * If the resulting {@code OffsetDateTime} is invalid, an exception is thrown.
     * 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 dayOfMonth  the day-of-month to set in the result, from 1 to 28-31
     * @return an {@code OffsetDateTime} based on this date-time with the requested day, not null
     * @throws DateTimeException if the day-of-month value is invalid
     * @throws DateTimeException if the day-of-month is invalid for the month-year
     */
    public OffsetDateTime withDayOfMonth(int dayOfMonth) {
        return with(dateTime.withDayOfMonth(dayOfMonth), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the day-of-year altered.
     * If the resulting {@code OffsetDateTime} is invalid, an exception is thrown.
     * <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 an {@code OffsetDateTime} based on this date with the requested day, not null
     * @throws DateTimeException if the day-of-year value is invalid
     * @throws DateTimeException if the day-of-year is invalid for the year
     */
    public OffsetDateTime withDayOfYear(int dayOfYear) {
        return with(dateTime.withDayOfYear(dayOfYear), offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this {@code OffsetDateTime} with the hour-of-day value 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 OffsetDateTime} based on this date-time with the requested hour, not null
     * @throws DateTimeException if the hour value is invalid
     */
    public OffsetDateTime withHour(int hour) {
        return with(dateTime.withHour(hour), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the minute-of-hour value 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 OffsetDateTime} based on this date-time with the requested minute, not null
     * @throws DateTimeException if the minute value is invalid
     */
    public OffsetDateTime withMinute(int minute) {
        return with(dateTime.withMinute(minute), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the second-of-minute value 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 OffsetDateTime} based on this date-time with the requested second, not null
     * @throws DateTimeException if the second value is invalid
     */
    public OffsetDateTime withSecond(int second) {
        return with(dateTime.withSecond(second), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the nano-of-second value 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 OffsetDateTime} based on this date-time with the requested nanosecond, not null
     * @throws DateTimeException if the nanos value is invalid
     */
    public OffsetDateTime withNano(int nanoOfSecond) {
        return with(dateTime.withNano(nanoOfSecond), offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this {@code OffsetDateTime} 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>
     * Not all units are accepted. The {@link ChronoUnit#DAYS days} unit and time
     * units with an exact duration can be used, 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 OffsetDateTime} based on this date-time with the time truncated, not null
     * @throws DateTimeException if unable to truncate
     */
    public OffsetDateTime truncatedTo(TemporalUnit unit) {
        return with(dateTime.truncatedTo(unit), offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this date-time with the specified period added.
     * <p>
     * This method returns a new date-time based on this time with the specified period added.
     * The adder is typically {@link Period} but may be any other type implementing
     * the {@link TemporalAdder} interface.
     * The calculation is delegated to the specified adjuster, which typically calls
     * back to {@link #plus(long, TemporalUnit)}.
     * The offset is not part of the calculation and will be unchanged in the result.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param adder  the adder to use, not null
     * @return an {@code OffsetDateTime} 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 OffsetDateTime plus(TemporalAdder adder) {
        return (OffsetDateTime) adder.addTo(this);
    }

    /**
     * Returns a copy of this date-time with the specified period added.
     * <p>
     * This method returns a new date-time based on this date-time with the specified period added.
     * This can be used to add any period that is defined by a unit, for example to add years, months or days.
     * The unit is responsible for the details of the calculation, including the resolution
     * of any edge cases in the calculation.
     * The offset is not part of the calculation and will be unchanged in the result.
     * <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 period to add, not null
     * @return an {@code OffsetDateTime} based on this date-time with the specified period added, not null
     * @throws DateTimeException if the unit cannot be added to this type
     */
    @Override
    public OffsetDateTime plus(long amountToAdd, TemporalUnit unit) {
        if (unit instanceof ChronoUnit) {
            return with(dateTime.plus(amountToAdd, unit), offset);
        }
        return unit.doPlus(this, amountToAdd);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in years added.
     * <p>
     * This method adds the specified amount to the years field in three steps:
     * <ol>
     * <li>Add the input years to the year field</li>
     * <li>Check if the resulting date would be invalid</li>
     * <li>Adjust the day-of-month to the last valid day if necessary</li>
     * </ol>
     * <p>
     * For example, 2008-02-29 (leap year) plus one year would result in the
     * invalid date 2009-02-29 (standard year). Instead of returning an invalid
     * result, the last valid day of the month, 2009-02-28, is selected instead.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param years  the years to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the years added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusYears(long years) {
        return with(dateTime.plusYears(years), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in months added.
     * <p>
     * This method adds the specified amount to the months field in three steps:
     * <ol>
     * <li>Add the input months to the month-of-year field</li>
     * <li>Check if the resulting date would be invalid</li>
     * <li>Adjust the day-of-month to the last valid day if necessary</li>
     * </ol>
     * <p>
     * For example, 2007-03-31 plus one month would result in the invalid date
     * 2007-04-31. Instead of returning an invalid result, the last valid day
     * of the month, 2007-04-30, is selected instead.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param months  the months to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the months added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusMonths(long months) {
        return with(dateTime.plusMonths(months), offset);
    }

    /**
     * Returns a copy of this OffsetDateTime with the specified period in weeks added.
     * <p>
     * This method adds the specified amount in weeks to the days field incrementing
     * the month and year fields as necessary to ensure the result remains valid.
     * The result is only invalid if the maximum/minimum year is exceeded.
     * <p>
     * For example, 2008-12-31 plus one week would result in the 2009-01-07.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param weeks  the weeks to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the weeks added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusWeeks(long weeks) {
        return with(dateTime.plusWeeks(weeks), offset);
    }

    /**
     * Returns a copy of this OffsetDateTime with the specified period in days added.
     * <p>
     * This method adds the specified amount to the days field incrementing the
     * month and year fields as necessary to ensure the result remains valid.
     * The result is only invalid if the maximum/minimum year is exceeded.
     * <p>
     * For example, 2008-12-31 plus one day would result in the 2009-01-01.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param days  the days to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the days added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusDays(long days) {
        return with(dateTime.plusDays(days), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in hours added.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param hours  the hours to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the hours added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusHours(long hours) {
        return with(dateTime.plusHours(hours), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in minutes added.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param minutes  the minutes to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the minutes added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusMinutes(long minutes) {
        return with(dateTime.plusMinutes(minutes), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in seconds added.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param seconds  the seconds to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the seconds added, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime plusSeconds(long seconds) {
        return with(dateTime.plusSeconds(seconds), offset);
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in nanoseconds added.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param nanos  the nanos to add, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the nanoseconds added, not null
     * @throws DateTimeException if the unit cannot be added to this type
     */
    public OffsetDateTime plusNanos(long nanos) {
        return with(dateTime.plusNanos(nanos), offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a copy of this date-time with the specified period subtracted.
     * <p>
     * This method returns a new date-time based on this time with the specified period subtracted.
     * The subtractor is typically {@link Period} but may be any other type implementing
     * the {@link TemporalSubtractor} interface.
     * The calculation is delegated to the specified adjuster, which typically calls
     * back to {@link #minus(long, TemporalUnit)}.
     * The offset is not part of the calculation and will be unchanged in the result.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param subtractor  the subtractor to use, not null
     * @return an {@code OffsetDateTime} 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 OffsetDateTime minus(TemporalSubtractor subtractor) {
        return (OffsetDateTime) subtractor.subtractFrom(this);
    }

    /**
     * Returns a copy of this date-time with the specified period subtracted.
     * <p>
     * This method returns a new date-time based on this date-time with the specified period subtracted.
     * This can be used to subtract any period that is defined by a unit, for example to subtract years, months or days.
     * The unit is responsible for the details of the calculation, including the resolution
     * of any edge cases in the calculation.
     * The offset is not part of the calculation and will be unchanged in the result.
     * <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 period to subtract, not null
     * @return an {@code OffsetDateTime} based on this date-time with the specified period subtracted, not null
     */
    @Override
    public OffsetDateTime 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 OffsetDateTime} with the specified period in years subtracted.
     * <p>
     * This method subtracts the specified amount from the years field in three steps:
     * <ol>
     * <li>Subtract the input years to the year field</li>
     * <li>Check if the resulting date would be invalid</li>
     * <li>Adjust the day-of-month to the last valid day if necessary</li>
     * </ol>
     * <p>
     * For example, 2008-02-29 (leap year) minus one year would result in the
     * invalid date 2009-02-29 (standard year). Instead of returning an invalid
     * result, the last valid day of the month, 2009-02-28, is selected instead.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param years  the years to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the years subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusYears(long years) {
        return (years == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-years));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in months subtracted.
     * <p>
     * This method subtracts the specified amount from the months field in three steps:
     * <ol>
     * <li>Subtract the input months to the month-of-year field</li>
     * <li>Check if the resulting date would be invalid</li>
     * <li>Adjust the day-of-month to the last valid day if necessary</li>
     * </ol>
     * <p>
     * For example, 2007-03-31 minus one month would result in the invalid date
     * 2007-04-31. Instead of returning an invalid result, the last valid day
     * of the month, 2007-04-30, is selected instead.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param months  the months to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the months subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusMonths(long months) {
        return (months == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-months));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in weeks subtracted.
     * <p>
     * This method subtracts the specified amount in weeks from the days field decrementing
     * the month and year fields as necessary to ensure the result remains valid.
     * The result is only invalid if the maximum/minimum year is exceeded.
     * <p>
     * For example, 2008-12-31 minus one week would result in the 2009-01-07.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param weeks  the weeks to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the weeks subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusWeeks(long weeks) {
        return (weeks == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeks));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in days subtracted.
     * <p>
     * This method subtracts the specified amount from the days field incrementing the
     * month and year fields as necessary to ensure the result remains valid.
     * The result is only invalid if the maximum/minimum year is exceeded.
     * <p>
     * For example, 2008-12-31 minus one day would result in the 2009-01-01.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param days  the days to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the days subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusDays(long days) {
        return (days == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-days));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in hours subtracted.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param hours  the hours to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the hours subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusHours(long hours) {
        return (hours == Long.MIN_VALUE ? plusHours(Long.MAX_VALUE).plusHours(1) : plusHours(-hours));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in minutes subtracted.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param minutes  the minutes to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the minutes subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusMinutes(long minutes) {
        return (minutes == Long.MIN_VALUE ? plusMinutes(Long.MAX_VALUE).plusMinutes(1) : plusMinutes(-minutes));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in seconds subtracted.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param seconds  the seconds to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the seconds subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime minusSeconds(long seconds) {
        return (seconds == Long.MIN_VALUE ? plusSeconds(Long.MAX_VALUE).plusSeconds(1) : plusSeconds(-seconds));
    }

    /**
     * Returns a copy of this {@code OffsetDateTime} with the specified period in nanoseconds subtracted.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param nanos  the nanos to subtract, may be negative
     * @return an {@code OffsetDateTime} based on this date-time with the nanoseconds subtracted, not null
     * @throws DateTimeException if the result exceeds the supported date range
     */
    public OffsetDateTime 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
    public <R> R query(TemporalQuery<R> query) {
        if (query == TemporalQueries.chrono()) {
            return (R) getDate().getChrono();
        } else if (query == TemporalQueries.precision()) {
            return (R) NANOS;
        } else if (query == TemporalQueries.offset() || query == TemporalQueries.zone()) {
            return (R) getOffset();
        }
        return super.query(query);
    }

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

    /**
     * Calculates the period between this date-time and another date-time in
     * terms of the specified unit.
     * <p>
     * This calculates the period between two date-times in terms of a single unit.
     * 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 period in days between two date-times can be calculated
     * using {@code startDateTime.periodUntil(endDateTime, DAYS)}.
     * <p>
     * The {@code Temporal} passed to this method must be an {@code OffsetDateTime}.
     * If the offset differs between the two date-times, the specified
     * end date-time is normalized to have the same offset 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 period 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>
     * This method operates in association with {@link TemporalUnit#between}.
     * The result of this method is a {@code long} representing the amount of
     * the specified unit. By contrast, the result of {@code between} is an
     * object that can be used directly in addition/subtraction:
     * <pre>
     *   long period = start.periodUntil(end, MONTHS);   // this method
     *   dateTime.plus(MONTHS.between(start, end));      // use in plus/minus
     * </pre>
     * <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>
     * 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 input temporal as
     * the second argument.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param endDateTime  the end date-time, which must be an {@code OffsetDateTime}, not null
     * @param unit  the unit to measure the period in, not null
     * @return the amount of the period between this date-time and the end date-time
     * @throws DateTimeException if the period cannot be calculated
     * @throws ArithmeticException if numeric overflow occurs
     */
    @Override
    public long periodUntil(Temporal endDateTime, TemporalUnit unit) {
        if (endDateTime instanceof OffsetDateTime == false) {
            Objects.requireNonNull(endDateTime, "endDateTime");
            throw new DateTimeException("Unable to calculate period between objects of two different types");
        }
        if (unit instanceof ChronoUnit) {
            OffsetDateTime end = (OffsetDateTime) endDateTime;
            end = end.withOffsetSameInstant(offset);
            return dateTime.periodUntil(end.dateTime, unit);
        }
        return unit.between(this, endDateTime).getAmount();
    }

    //-----------------------------------------------------------------------
    /**
     * Returns a zoned date-time formed from the instant represented by this
     * date-time and the specified zone ID.
     * <p>
     * This conversion will ignore the visible local date-time and use the underlying instant instead.
     * This avoids any problems with local time-line gaps or overlaps.
     * The result might have different values for fields such as hour, minute an even day.
     * <p>
     * To attempt to retain the values of the fields, use {@link #atZoneSimilarLocal(ZoneId)}.
     * To use the offset as the zone ID, use {@link #toZonedDateTime()}.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param zone  the time-zone to use, not null
     * @return the zoned date-time formed from this date-time, not null
     */
    public ZonedDateTime atZoneSameInstant(ZoneId zone) {
        return ZonedDateTime.ofInstant(dateTime, offset, zone);
    }

    /**
     * Returns a zoned date-time formed from this date-time and the specified zone ID.
     * <p>
     * Time-zone rules, such as daylight savings, mean that not every time on the
     * local time-line exists. If the local date-time is in a gap or overlap according to
     * the rules then a resolver is used to determine the resultant local time and offset.
     * This method uses {@link ZonedDateTime#ofLocal(LocalDateTime, ZoneId, ZoneOffset)}
     * to retain the offset from this instance if possible.
     * <p>
     * Finer control over gaps and overlaps is available in two ways.
     * If you simply want to use the later offset at overlaps then call
     * {@link ZonedDateTime#withLaterOffsetAtOverlap()} immediately after this method.
     * <p>
     * To create a zoned date-time at the same instant irrespective of the local time-line,
     * use {@link #atZoneSameInstant(ZoneId)}.
     * To use the offset as the zone ID, use {@link #toZonedDateTime()}.
     * <p>
     * This instance is immutable and unaffected by this method call.
     *
     * @param zone  the time-zone to use, not null
     * @return the zoned date-time formed from this date and the earliest valid time for the zone, not null
     */
    public ZonedDateTime atZoneSimilarLocal(ZoneId zone) {
        return ZonedDateTime.ofLocal(dateTime, zone, offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Converts this date-time to an {@code OffsetDate}.
     * <p>
     * This returns an offset date with the same local date and offset.
     *
     * @return an OffsetDate representing the date and offset, not null
     */
    public OffsetDate toOffsetDate() {
        return OffsetDate.of(dateTime.getDate(), offset);
    }

    /**
     * Converts this date-time to an {@code OffsetTime}.
     * <p>
     * This returns an offset time with the same local time and offset.
     *
     * @return an OffsetTime representing the time and offset, not null
     */
    public OffsetTime toOffsetTime() {
        return OffsetTime.of(dateTime.getTime(), offset);
    }

    /**
     * Converts this date-time to a {@code ZonedDateTime} using the offset as the zone ID.
     * <p>
     * This creates the simplest possible {@code ZonedDateTime} using the offset
     * as the zone ID.
     * <p>
     * To control the time-zone used, see {@link #atZoneSameInstant(ZoneId)} and
     * {@link #atZoneSimilarLocal(ZoneId)}.
     *
     * @return a zoned date-time representing the same local date-time and offset, not null
     */
    public ZonedDateTime toZonedDateTime() {
        return ZonedDateTime.of(dateTime, offset);
    }

    /**
     * Converts this date-time to an {@code Instant}.
     *
     * @return an {@code Instant} representing the same instant, not null
     */
    public Instant toInstant() {
        return dateTime.toInstant(offset);
    }

    /**
     * Converts this date-time to the number of seconds from the epoch of 1970-01-01T00:00:00Z.
     * <p>
     * This allows this date-time to be converted to a value of the
     * {@link ChronoField#INSTANT_SECONDS epoch-seconds} field. This is primarily
     * intended for low-level conversions rather than general application usage.
     *
     * @return the number of seconds from the epoch of 1970-01-01T00:00:00Z
     */
    public long toEpochSecond() {
        return dateTime.toEpochSecond(offset);
    }

    //-----------------------------------------------------------------------
    /**
     * Compares this {@code OffsetDateTime} to another date-time.
     * <p>
     * The comparison is based on the instant then on the local date-time.
     * It is "consistent with equals", as defined by {@link Comparable}.
     * <p>
     * For example, the following is the comparator order:
     * <ol>
     * <li>{@code 2008-12-03T10:30+01:00}</li>
     * <li>{@code 2008-12-03T11:00+01:00}</li>
     * <li>{@code 2008-12-03T12:00+02:00}</li>
     * <li>{@code 2008-12-03T11:30+01:00}</li>
     * <li>{@code 2008-12-03T12:00+01:00}</li>
     * <li>{@code 2008-12-03T12:30+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 date-time is compared
     * to distinguish them. This step is needed to make the ordering
     * consistent with {@code equals()}.
     *
     * @param other  the other date-time to compare to, not null
     * @return the comparator value, negative if less, positive if greater
     */
    @Override
    public int compareTo(OffsetDateTime other) {
        if (getOffset().equals(other.getOffset())) {
            return getDateTime().compareTo(other.getDateTime());
        }
        int cmp = Long.compare(toEpochSecond(), other.toEpochSecond());
        if (cmp == 0) {
            cmp = getTime().getNano() - other.getTime().getNano();
            if (cmp == 0) {
                cmp = getDateTime().compareTo(other.getDateTime());
            }
        }
        return cmp;
    }

    //-----------------------------------------------------------------------
    /**
     * Checks if the instant of this date-time is after that of the specified date-time.
     * <p>
     * This method differs from the comparison in {@link #compareTo} and {@link #equals} in that it
     * only compares the instant of the date-time. This is equivalent to using
     * {@code dateTime1.toInstant().isAfter(dateTime2.toInstant());}.
     *
     * @param other  the other date-time to compare to, not null
     * @return true if this is after the instant of the specified date-time
     */
    public boolean isAfter(OffsetDateTime other) {
        long thisEpochSec = toEpochSecond();
        long otherEpochSec = other.toEpochSecond();
        return thisEpochSec > otherEpochSec ||
            (thisEpochSec == otherEpochSec && getTime().getNano() > other.getTime().getNano());
    }

    /**
     * Checks if the instant of this date-time is before that of the specified date-time.
     * <p>
     * This method differs from the comparison in {@link #compareTo} in that it
     * only compares the instant of the date-time. This is equivalent to using
     * {@code dateTime1.toInstant().isBefore(dateTime2.toInstant());}.
     *
     * @param other  the other date-time to compare to, not null
     * @return true if this is before the instant of the specified date-time
     */
    public boolean isBefore(OffsetDateTime other) {
        long thisEpochSec = toEpochSecond();
        long otherEpochSec = other.toEpochSecond();
        return thisEpochSec < otherEpochSec ||
            (thisEpochSec == otherEpochSec && getTime().getNano() < other.getTime().getNano());
    }

    /**
     * Checks if the instant of this date-time is equal to that of the specified date-time.
     * <p>
     * This method differs from the comparison in {@link #compareTo} and {@link #equals}
     * in that it only compares the instant of the date-time. This is equivalent to using
     * {@code dateTime1.toInstant().equals(dateTime2.toInstant());}.
     *
     * @param other  the other date-time to compare to, not null
     * @return true if the instant equals the instant of the specified date-time
     */
    public boolean isEqual(OffsetDateTime other) {
        return toEpochSecond() == other.toEpochSecond() &&
                getTime().getNano() == other.getTime().getNano();
    }

    //-----------------------------------------------------------------------
    /**
     * Checks if this date-time is equal to another date-time.
     * <p>
     * The comparison is based on the local date-time and the offset.
     * To compare for the same instant on the time-line, use {@link #isEqual}.
     * Only objects of type {@code OffsetDateTime} 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 OffsetDateTime) {
            OffsetDateTime other = (OffsetDateTime) obj;
            return dateTime.equals(other.dateTime) && offset.equals(other.offset);
        }
        return false;
    }

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

    //-----------------------------------------------------------------------
    /**
     * Outputs this date-time as a {@code String}, such as {@code 2007-12-03T10:15:30+01:00}.
     * <p>
     * The output will be one of the following ISO-8601 formats:
     * <p><ul>
     * <li>{@code yyyy-MM-dd'T'HH:mmXXXXX}</li>
     * <li>{@code yyyy-MM-dd'T'HH:mm:ssXXXXX}</li>
     * <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSXXXXX}</li>
     * <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSSSSXXXXX}</li>
     * <li>{@code yyyy-MM-dd'T'HH:mm:ss.SSSSSSSSSXXXXX}</li>
     * </ul><p>
     * 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 date-time, not null
     */
    @Override
    public String toString() {
        return dateTime.toString() + offset.toString();
    }

    /**
     * Outputs this date-time as a {@code String} using the formatter.
     * <p>
     * This date-time will be passed to the formatter
     * {@link DateTimeFormatter#print(TemporalAccessor) print method}.
     *
     * @param formatter  the formatter to use, not null
     * @return the formatted date-time string, not null
     * @throws DateTimeException if an error occurs during printing
     */
    public String toString(DateTimeFormatter formatter) {
        Objects.requireNonNull(formatter, "formatter");
        return formatter.print(this);
    }

    //-----------------------------------------------------------------------
    private Object writeReplace() {
        return new Ser(Ser.OFFSET_DATE_TIME_TYPE, this);
    }

    /**
     * Defend against malicious streams.
     * @return never
     * @throws InvalidObjectException always
     */
    private Object readResolve() throws ObjectStreamException {
        throw new InvalidObjectException("Deserialization via serialization delegate");
    }

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

    static OffsetDateTime readExternal(DataInput in) throws IOException {
        LocalDateTime dateTime = LocalDateTime.readExternal(in);
        ZoneOffset offset = ZoneOffset.readExternal(in);
        return OffsetDateTime.of(dateTime, offset);
    }

}