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/*
* Copyright (c) 2007-present, 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.zone;
import static org.threeten.bp.temporal.TemporalAdjusters.nextOrSame;
import static org.threeten.bp.temporal.TemporalAdjusters.previousOrSame;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.Serializable;
import org.threeten.bp.DayOfWeek;
import org.threeten.bp.LocalDate;
import org.threeten.bp.LocalDateTime;
import org.threeten.bp.LocalTime;
import org.threeten.bp.Month;
import org.threeten.bp.ZoneOffset;
import org.threeten.bp.chrono.IsoChronology;
import org.threeten.bp.jdk8.Jdk8Methods;
/**
* A rule expressing how to create a transition.
*
* This class allows rules for identifying future transitions to be expressed.
* A rule might be written in many forms:
*
* - the 16th March
*
- the Sunday on or after the 16th March
*
- the Sunday on or before the 16th March
*
- the last Sunday in February
*
* These different rule types can be expressed and queried.
*
*
Specification for implementors
* This class is immutable and thread-safe.
*/
public final class ZoneOffsetTransitionRule implements Serializable {
/**
* Serialization version.
*/
private static final long serialVersionUID = 6889046316657758795L;
/**
* The number of seconds per day.
*/
private static final int SECS_PER_DAY = 86400;
/**
* The month of the month-day of the first day of the cutover week.
* The actual date will be adjusted by the dowChange field.
*/
private final Month month;
/**
* The day-of-month of the month-day of the cutover week.
* If positive, it is the start of the week where the cutover can occur.
* If negative, it represents the end of the week where cutover can occur.
* The value is the number of days from the end of the month, such that
* {@code -1} is the last day of the month, {@code -2} is the second
* to last day, and so on.
*/
private final byte dom;
/**
* The cutover day-of-week, null to retain the day-of-month.
*/
private final DayOfWeek dow;
/**
* The cutover time in the 'before' offset.
*/
private final LocalTime time;
/**
* The number of days to adjust by.
*/
private final int adjustDays;
/**
* The definition of how the local time should be interpreted.
*/
private final TimeDefinition timeDefinition;
/**
* The standard offset at the cutover.
*/
private final ZoneOffset standardOffset;
/**
* The offset before the cutover.
*/
private final ZoneOffset offsetBefore;
/**
* The offset after the cutover.
*/
private final ZoneOffset offsetAfter;
/**
* Obtains an instance defining the yearly rule to create transitions between two offsets.
*
* Applications should normally obtain an instance from {@link ZoneRules}.
* This factory is only intended for use when creating {@link ZoneRules}.
*
* @param month the month of the month-day of the first day of the cutover week, not null
* @param dayOfMonthIndicator the day of the month-day of the cutover week, positive if the week is that
* day or later, negative if the week is that day or earlier, counting from the last day of the month,
* from -28 to 31 excluding 0
* @param dayOfWeek the required day-of-week, null if the month-day should not be changed
* @param time the cutover time in the 'before' offset, not null
* @param timeEndOfDay whether the time is midnight at the end of day
* @param timeDefnition how to interpret the cutover
* @param standardOffset the standard offset in force at the cutover, not null
* @param offsetBefore the offset before the cutover, not null
* @param offsetAfter the offset after the cutover, not null
* @return the rule, not null
* @throws IllegalArgumentException if the day of month indicator is invalid
* @throws IllegalArgumentException if the end of day flag is true when the time is not midnight
*/
public static ZoneOffsetTransitionRule of(
Month month,
int dayOfMonthIndicator,
DayOfWeek dayOfWeek,
LocalTime time,
boolean timeEndOfDay,
TimeDefinition timeDefnition,
ZoneOffset standardOffset,
ZoneOffset offsetBefore,
ZoneOffset offsetAfter) {
Jdk8Methods.requireNonNull(month, "month");
Jdk8Methods.requireNonNull(time, "time");
Jdk8Methods.requireNonNull(timeDefnition, "timeDefnition");
Jdk8Methods.requireNonNull(standardOffset, "standardOffset");
Jdk8Methods.requireNonNull(offsetBefore, "offsetBefore");
Jdk8Methods.requireNonNull(offsetAfter, "offsetAfter");
if (dayOfMonthIndicator < -28 || dayOfMonthIndicator > 31 || dayOfMonthIndicator == 0) {
throw new IllegalArgumentException("Day of month indicator must be between -28 and 31 inclusive excluding zero");
}
if (timeEndOfDay && time.equals(LocalTime.MIDNIGHT) == false) {
throw new IllegalArgumentException("Time must be midnight when end of day flag is true");
}
return new ZoneOffsetTransitionRule(month, dayOfMonthIndicator, dayOfWeek, time, timeEndOfDay ? 1 : 0, timeDefnition, standardOffset, offsetBefore, offsetAfter);
}
/**
* Creates an instance defining the yearly rule to create transitions between two offsets.
*
* @param month the month of the month-day of the first day of the cutover week, not null
* @param dayOfMonthIndicator the day of the month-day of the cutover week, positive if the week is that
* day or later, negative if the week is that day or earlier, counting from the last day of the month,
* from -28 to 31 excluding 0
* @param dayOfWeek the required day-of-week, null if the month-day should not be changed
* @param time the cutover time in the 'before' offset, not null
* @param adjustDays the time days adjustment
* @param timeDefnition how to interpret the cutover
* @param standardOffset the standard offset in force at the cutover, not null
* @param offsetBefore the offset before the cutover, not null
* @param offsetAfter the offset after the cutover, not null
* @throws IllegalArgumentException if the day of month indicator is invalid
* @throws IllegalArgumentException if the end of day flag is true when the time is not midnight
*/
ZoneOffsetTransitionRule(
Month month,
int dayOfMonthIndicator,
DayOfWeek dayOfWeek,
LocalTime time,
int adjustDays,
TimeDefinition timeDefnition,
ZoneOffset standardOffset,
ZoneOffset offsetBefore,
ZoneOffset offsetAfter) {
this.month = month;
this.dom = (byte) dayOfMonthIndicator;
this.dow = dayOfWeek;
this.time = time;
this.adjustDays = adjustDays;
this.timeDefinition = timeDefnition;
this.standardOffset = standardOffset;
this.offsetBefore = offsetBefore;
this.offsetAfter = offsetAfter;
}
//-----------------------------------------------------------------------
/**
* Uses a serialization delegate.
*
* @return the replacing object, not null
*/
private Object writeReplace() {
return new Ser(Ser.ZOTRULE, this);
}
/**
* Writes the state to the stream.
*
* @param out the output stream, not null
* @throws IOException if an error occurs
*/
void writeExternal(DataOutput out) throws IOException {
final int timeSecs = time.toSecondOfDay() + adjustDays * SECS_PER_DAY;
final int stdOffset = standardOffset.getTotalSeconds();
final int beforeDiff = offsetBefore.getTotalSeconds() - stdOffset;
final int afterDiff = offsetAfter.getTotalSeconds() - stdOffset;
final int timeByte = (timeSecs % 3600 == 0 && timeSecs <= SECS_PER_DAY ?
(timeSecs == SECS_PER_DAY ? 24 : time.getHour()) : 31);
final int stdOffsetByte = (stdOffset % 900 == 0 ? stdOffset / 900 + 128 : 255);
final int beforeByte = (beforeDiff == 0 || beforeDiff == 1800 || beforeDiff == 3600 ? beforeDiff / 1800 : 3);
final int afterByte = (afterDiff == 0 || afterDiff == 1800 || afterDiff == 3600 ? afterDiff / 1800 : 3);
final int dowByte = (dow == null ? 0 : dow.getValue());
int b = (month.getValue() << 28) + // 4 bits
((dom + 32) << 22) + // 6 bits
(dowByte << 19) + // 3 bits
(timeByte << 14) + // 5 bits
(timeDefinition.ordinal() << 12) + // 2 bits
(stdOffsetByte << 4) + // 8 bits
(beforeByte << 2) + // 2 bits
afterByte; // 2 bits
out.writeInt(b);
if (timeByte == 31) {
out.writeInt(timeSecs);
}
if (stdOffsetByte == 255) {
out.writeInt(stdOffset);
}
if (beforeByte == 3) {
out.writeInt(offsetBefore.getTotalSeconds());
}
if (afterByte == 3) {
out.writeInt(offsetAfter.getTotalSeconds());
}
}
/**
* Reads the state from the stream.
*
* @param in the input stream, not null
* @return the created object, not null
* @throws IOException if an error occurs
*/
static ZoneOffsetTransitionRule readExternal(DataInput in) throws IOException {
int data = in.readInt();
Month month = Month.of(data >>> 28);
int dom = ((data & (63 << 22)) >>> 22) - 32;
int dowByte = (data & (7 << 19)) >>> 19;
DayOfWeek dow = dowByte == 0 ? null : DayOfWeek.of(dowByte);
int timeByte = (data & (31 << 14)) >>> 14;
TimeDefinition defn = TimeDefinition.values()[(data & (3 << 12)) >>> 12];
int stdByte = (data & (255 << 4)) >>> 4;
int beforeByte = (data & (3 << 2)) >>> 2;
int afterByte = (data & 3);
int timeOfDaysSecs = (timeByte == 31 ? in.readInt() : timeByte * 3600);
ZoneOffset std = (stdByte == 255 ? ZoneOffset.ofTotalSeconds(in.readInt()) : ZoneOffset.ofTotalSeconds((stdByte - 128) * 900));
ZoneOffset before = (beforeByte == 3 ? ZoneOffset.ofTotalSeconds(in.readInt()) : ZoneOffset.ofTotalSeconds(std.getTotalSeconds() + beforeByte * 1800));
ZoneOffset after = (afterByte == 3 ? ZoneOffset.ofTotalSeconds(in.readInt()) : ZoneOffset.ofTotalSeconds(std.getTotalSeconds() + afterByte * 1800));
// only bit of validation that we need to copy from public of() method
if (dom < -28 || dom > 31 || dom == 0) {
throw new IllegalArgumentException("Day of month indicator must be between -28 and 31 inclusive excluding zero");
}
LocalTime time = LocalTime.ofSecondOfDay(Jdk8Methods.floorMod(timeOfDaysSecs, SECS_PER_DAY));
int adjustDays = Jdk8Methods.floorDiv(timeOfDaysSecs, SECS_PER_DAY);
return new ZoneOffsetTransitionRule(month, dom, dow, time, adjustDays, defn, std, before, after);
}
//-----------------------------------------------------------------------
/**
* Gets the month of the transition.
*
* If the rule defines an exact date then the month is the month of that date.
*
* If the rule defines a week where the transition might occur, then the month
* if the month of either the earliest or latest possible date of the cutover.
*
* @return the month of the transition, not null
*/
public Month getMonth() {
return month;
}
/**
* Gets the indicator of the day-of-month of the transition.
*
* If the rule defines an exact date then the day is the month of that date.
*
* If the rule defines a week where the transition might occur, then the day
* defines either the start of the end of the transition week.
*
* If the value is positive, then it represents a normal day-of-month, and is the
* earliest possible date that the transition can be.
* The date may refer to 29th February which should be treated as 1st March in non-leap years.
*
* If the value is negative, then it represents the number of days back from the
* end of the month where {@code -1} is the last day of the month.
* In this case, the day identified is the latest possible date that the transition can be.
*
* @return the day-of-month indicator, from -28 to 31 excluding 0
*/
public int getDayOfMonthIndicator() {
return dom;
}
/**
* Gets the day-of-week of the transition.
*
* If the rule defines an exact date then this returns null.
*
* If the rule defines a week where the cutover might occur, then this method
* returns the day-of-week that the month-day will be adjusted to.
* If the day is positive then the adjustment is later.
* If the day is negative then the adjustment is earlier.
*
* @return the day-of-week that the transition occurs, null if the rule defines an exact date
*/
public DayOfWeek getDayOfWeek() {
return dow;
}
/**
* Gets the local time of day of the transition which must be checked with
* {@link #isMidnightEndOfDay()}.
*
* The time is converted into an instant using the time definition.
*
* @return the local time of day of the transition, not null
*/
public LocalTime getLocalTime() {
return time;
}
/**
* Is the transition local time midnight at the end of day.
*
* The transition may be represented as occurring at 24:00.
*
* @return whether a local time of midnight is at the start or end of the day
*/
public boolean isMidnightEndOfDay() {
return adjustDays == 1 && time.equals(LocalTime.MIDNIGHT);
}
/**
* Gets the time definition, specifying how to convert the time to an instant.
*
* The local time can be converted to an instant using the standard offset,
* the wall offset or UTC.
*
* @return the time definition, not null
*/
public TimeDefinition getTimeDefinition() {
return timeDefinition;
}
/**
* Gets the standard offset in force at the transition.
*
* @return the standard offset, not null
*/
public ZoneOffset getStandardOffset() {
return standardOffset;
}
/**
* Gets the offset before the transition.
*
* @return the offset before, not null
*/
public ZoneOffset getOffsetBefore() {
return offsetBefore;
}
/**
* Gets the offset after the transition.
*
* @return the offset after, not null
*/
public ZoneOffset getOffsetAfter() {
return offsetAfter;
}
//-----------------------------------------------------------------------
/**
* Creates a transition instance for the specified year.
*
* Calculations are performed using the ISO-8601 chronology.
*
* @param year the year to create a transition for, not null
* @return the transition instance, not null
*/
public ZoneOffsetTransition createTransition(int year) {
LocalDate date;
if (dom < 0) {
date = LocalDate.of(year, month, month.length(IsoChronology.INSTANCE.isLeapYear(year)) + 1 + dom);
if (dow != null) {
date = date.with(previousOrSame(dow));
}
} else {
date = LocalDate.of(year, month, dom);
if (dow != null) {
date = date.with(nextOrSame(dow));
}
}
LocalDateTime localDT = LocalDateTime.of(date.plusDays(adjustDays), time);
LocalDateTime transition = timeDefinition.createDateTime(localDT, standardOffset, offsetBefore);
return new ZoneOffsetTransition(transition, offsetBefore, offsetAfter);
}
//-----------------------------------------------------------------------
/**
* Checks if this object equals another.
*
* The entire state of the object is compared.
*
* @param otherRule the other object to compare to, null returns false
* @return true if equal
*/
@Override
public boolean equals(Object otherRule) {
if (otherRule == this) {
return true;
}
if (otherRule instanceof ZoneOffsetTransitionRule) {
ZoneOffsetTransitionRule other = (ZoneOffsetTransitionRule) otherRule;
return month == other.month && dom == other.dom && dow == other.dow &&
timeDefinition == other.timeDefinition &&
adjustDays == other.adjustDays &&
time.equals(other.time) &&
standardOffset.equals(other.standardOffset) &&
offsetBefore.equals(other.offsetBefore) &&
offsetAfter.equals(other.offsetAfter);
}
return false;
}
/**
* Returns a suitable hash code.
*
* @return the hash code
*/
@Override
public int hashCode() {
int hash = ((time.toSecondOfDay() + adjustDays) << 15) +
(month.ordinal() << 11) + ((dom + 32) << 5) +
((dow == null ? 7 : dow.ordinal()) << 2) + (timeDefinition.ordinal());
return hash ^ standardOffset.hashCode() ^
offsetBefore.hashCode() ^ offsetAfter.hashCode();
}
//-----------------------------------------------------------------------
/**
* Returns a string describing this object.
*
* @return a string for debugging, not null
*/
@Override
public String toString() {
StringBuilder buf = new StringBuilder();
buf.append("TransitionRule[")
.append(offsetBefore.compareTo(offsetAfter) > 0 ? "Gap " : "Overlap ")
.append(offsetBefore).append(" to ").append(offsetAfter).append(", ");
if (dow != null) {
if (dom == -1) {
buf.append(dow.name()).append(" on or before last day of ").append(month.name());
} else if (dom < 0) {
buf.append(dow.name()).append(" on or before last day minus ").append(-dom - 1).append(" of ").append(month.name());
} else {
buf.append(dow.name()).append(" on or after ").append(month.name()).append(' ').append(dom);
}
} else {
buf.append(month.name()).append(' ').append(dom);
}
buf.append(" at ");
if (adjustDays == 0) {
buf.append(time);
} else {
long timeOfDaysMins = time.toSecondOfDay() / 60 + adjustDays * 24 * 60;
appendZeroPad(buf, Jdk8Methods.floorDiv(timeOfDaysMins, 60));
buf.append(':');
appendZeroPad(buf, Jdk8Methods.floorMod(timeOfDaysMins, 60));
}
buf.append(" ").append(timeDefinition)
.append(", standard offset ").append(standardOffset)
.append(']');
return buf.toString();
}
private void appendZeroPad(StringBuilder sb, long number) {
if (number < 10) {
sb.append(0);
}
sb.append(number);
}
//-----------------------------------------------------------------------
/**
* A definition of the way a local time can be converted to the actual
* transition date-time.
*
* Time zone rules are expressed in one of three ways:
*
* - Relative to UTC
* - Relative to the standard offset in force
* - Relative to the wall offset (what you would see on a clock on the wall)
*
*/
public static enum TimeDefinition {
/** The local date-time is expressed in terms of the UTC offset. */
UTC,
/** The local date-time is expressed in terms of the wall offset. */
WALL,
/** The local date-time is expressed in terms of the standard offset. */
STANDARD;
/**
* Converts the specified local date-time to the local date-time actually
* seen on a wall clock.
*
* This method converts using the type of this enum.
* The output is defined relative to the 'before' offset of the transition.
*
* The UTC type uses the UTC offset.
* The STANDARD type uses the standard offset.
* The WALL type returns the input date-time.
* The result is intended for use with the wall-offset.
*
* @param dateTime the local date-time, not null
* @param standardOffset the standard offset, not null
* @param wallOffset the wall offset, not null
* @return the date-time relative to the wall/before offset, not null
*/
public LocalDateTime createDateTime(LocalDateTime dateTime, ZoneOffset standardOffset, ZoneOffset wallOffset) {
switch (this) {
case UTC: {
int difference = wallOffset.getTotalSeconds() - ZoneOffset.UTC.getTotalSeconds();
return dateTime.plusSeconds(difference);
}
case STANDARD: {
int difference = wallOffset.getTotalSeconds() - standardOffset.getTotalSeconds();
return dateTime.plusSeconds(difference);
}
default: // WALL
return dateTime;
}
}
}
}