/*
* Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package java.time.calendrical;
import static java.time.calendrical.ChronoField.DAY_OF_MONTH;
import static java.time.calendrical.ChronoField.DAY_OF_WEEK;
import static java.time.calendrical.ChronoField.DAY_OF_YEAR;
import static java.time.calendrical.ChronoUnit.DAYS;
import static java.time.calendrical.ChronoUnit.MONTHS;
import static java.time.calendrical.ChronoUnit.YEARS;
import java.time.DayOfWeek;
import java.time.calendrical.DateTime.WithAdjuster;
import java.time.jdk8.Jdk7Methods;
/**
* Common implementations of {@code DateTime.WithAdjuster}.
* <p>
* Adjusters are the principal tool for altering date-times. An adjuster should not normally used directly.
* Instead it should be used as follows:
*
* <pre>
* date = date.with(adjuster);
* </pre>
* <p>
* The adjusters provided by this class are primarily intended to be pre-packaged and pre-tested pieces of
* business logic. They are especially useful to document the intent of code and often link well to
* requirements. For example, these two pieces of code do the same thing, but the former is clearer (assuming
* that there is a static import of this class):
*
* <pre>
* // direct manipulation
* date.withDayOfMonth(1).plusMonths(1).minusDays(1);
* // use of an adjuster from this class
* date.with(lastDayOfMonth());
* </pre>
*
* <h4>Implementation notes</h4> This is a thread-safe utility class. All returned adjusters are immutable and
* thread-safe.
*/
public final class DateTimeAdjusters {
/**
* Private constructor since this is a utility class.
*/
private DateTimeAdjusters() {
}
// -----------------------------------------------------------------------
/**
* Returns the "first day of month" adjuster, which returns a new date set to the first day of the current
* month.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2011-01-01.<br />
* The input 2011-02-15 will return 2011-02-01.
*
* @return the first day-of-month adjuster, not null
*/
public static WithAdjuster firstDayOfMonth() {
return Impl.FIRST_DAY_OF_MONTH;
}
/**
* Returns the "last day of month" adjuster, which returns a new date set to the last day of the current
* month.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2011-01-31.<br />
* The input 2011-02-15 will return 2011-02-28.<br />
* The input 2012-02-15 will return 2012-02-29 (leap year).<br />
* The input 2011-04-15 will return 2011-04-30.
*
* @return the last day-of-month adjuster, not null
*/
public static WithAdjuster lastDayOfMonth() {
return Impl.LAST_DAY_OF_MONTH;
}
/**
* Returns the "first day of next month" adjuster, which returns a new date set to the first day of the next
* month.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2011-02-01.<br />
* The input 2011-02-15 will return 2011-03-01.
*
* @return the first day of next month adjuster, not null
*/
public static WithAdjuster firstDayOfNextMonth() {
return Impl.FIRST_DAY_OF_NEXT_MONTH;
}
// -----------------------------------------------------------------------
/**
* Returns the "first day of year" adjuster, which returns a new date set to the first day of the current
* year.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2011-01-01.<br />
* The input 2011-02-15 will return 2011-01-01.<br />
*
* @return the first day-of-year adjuster, not null
*/
public static WithAdjuster firstDayOfYear() {
return Impl.FIRST_DAY_OF_YEAR;
}
/**
* Returns the "last day of year" adjuster, which returns a new date set to the last day of the current
* year.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2011-12-31.<br />
* The input 2011-02-15 will return 2011-12-31.<br />
*
* @return the last day-of-year adjuster, not null
*/
public static WithAdjuster lastDayOfYear() {
return Impl.LAST_DAY_OF_YEAR;
}
/**
* Returns the "first day of next year" adjuster, which returns a new date set to the first day of the next
* year.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 will return 2012-01-01.
*
* @return the first day of next month adjuster, not null
*/
public static WithAdjuster firstDayOfNextYear() {
return Impl.FIRST_DAY_OF_NEXT_YEAR;
}
// -----------------------------------------------------------------------
/**
* Enum implementing the adjusters.
*/
private static enum Impl implements WithAdjuster {
/** First day of month adjuster. */
FIRST_DAY_OF_MONTH,
/** Last day of month adjuster. */
LAST_DAY_OF_MONTH,
/** First day of next month adjuster. */
FIRST_DAY_OF_NEXT_MONTH,
/** First day of year adjuster. */
FIRST_DAY_OF_YEAR,
/** Last day of year adjuster. */
LAST_DAY_OF_YEAR,
/** First day of next month adjuster. */
FIRST_DAY_OF_NEXT_YEAR;
@Override
public DateTime doWithAdjustment(DateTime dateTime) {
switch (this) {
case FIRST_DAY_OF_MONTH:
return dateTime.with(DAY_OF_MONTH, 1);
case LAST_DAY_OF_MONTH:
return dateTime.with(DAY_OF_MONTH, dateTime.range(DAY_OF_MONTH).getMaximum());
case FIRST_DAY_OF_NEXT_MONTH:
return dateTime.with(DAY_OF_MONTH, 1).plus(1, MONTHS);
case FIRST_DAY_OF_YEAR:
return dateTime.with(DAY_OF_YEAR, 1);
case LAST_DAY_OF_YEAR:
return dateTime.with(DAY_OF_YEAR, dateTime.range(DAY_OF_YEAR).getMaximum());
case FIRST_DAY_OF_NEXT_YEAR:
return dateTime.with(DAY_OF_YEAR, 1).plus(1, YEARS);
}
throw new IllegalStateException("Unreachable");
}
}
// -----------------------------------------------------------------------
/**
* Returns the first in month adjuster, which returns a new date in the same month with the first matching
* day-of-week. This is used for expressions like 'first Tuesday in March'.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-12-15 for (MONDAY) will return 2011-12-05.<br />
* The input 2011-12-15 for (FRIDAY) will return 2011-12-02.<br />
*
* @param dayOfWeek the day-of-week, not null
* @return the first in month adjuster, not null
*/
public static WithAdjuster firstInMonth(DayOfWeek dayOfWeek) {
Jdk7Methods.Objects_requireNonNull(dayOfWeek, "dayOfWeek");
return new DayOfWeekInMonth(1, dayOfWeek);
}
/**
* Returns the last in month adjuster, which returns a new date in the same month with the last matching
* day-of-week. This is used for expressions like 'last Tuesday in March'.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-12-15 for (MONDAY) will return 2011-12-26.<br />
* The input 2011-12-15 for (FRIDAY) will return 2011-12-30.<br />
*
* @param dayOfWeek the day-of-week, not null
* @return the first in month adjuster, not null
*/
public static WithAdjuster lastInMonth(DayOfWeek dayOfWeek) {
Jdk7Methods.Objects_requireNonNull(dayOfWeek, "dayOfWeek");
return new DayOfWeekInMonth(-1, dayOfWeek);
}
/**
* Returns the day-of-week in month adjuster, which returns a new date in the same month with the ordinal
* day-of-week. This is used for expressions like the 'second Tuesday in March'.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-12-15 for (1,TUESDAY) will return 2011-12-06.<br />
* The input 2011-12-15 for (2,TUESDAY) will return 2011-12-13.<br />
* The input 2011-12-15 for (3,TUESDAY) will return 2011-12-20.<br />
* The input 2011-12-15 for (4,TUESDAY) will return 2011-12-27.<br />
* The input 2011-12-15 for (5,TUESDAY) will return 2012-01-03.<br />
* The input 2011-12-15 for (-1,TUESDAY) will return 2011-12-27 (last in month).<br />
* The input 2011-12-15 for (-4,TUESDAY) will return 2011-12-06 (3 weeks before last in month).<br />
* The input 2011-12-15 for (-5,TUESDAY) will return 2011-11-29 (4 weeks before last in month).<br />
* The input 2011-12-15 for (0,TUESDAY) will return 2011-11-29 (last in previous month).<br />
* <p>
* For a positive or zero ordinal, the algorithm is equivalent to finding the first day-of-week that matches
* within the month and then adding a number of weeks to it. For a negative ordinal, the algorithm is
* equivalent to finding the last day-of-week that matches within the month and then subtracting a number of
* weeks to it. The ordinal number of weeks is not validated and is interpreted leniently according to this
* algorithm. This definition means that an ordinal of zero finds the last matching day-of-week in the
* previous month.
*
* @param ordinal the week within the month, unbound but typically from 1 to 5
* @param dayOfWeek the day-of-week, not null
* @return the day-of-week in month adjuster, not null
* @throws IllegalArgumentException if the ordinal is invalid
*/
public static WithAdjuster dayOfWeekInMonth(int ordinal, DayOfWeek dayOfWeek) {
Jdk7Methods.Objects_requireNonNull(dayOfWeek, "dayOfWeek");
return new DayOfWeekInMonth(ordinal, dayOfWeek);
}
/**
* Class implementing day-of-week in month adjuster.
*/
private static final class DayOfWeekInMonth implements WithAdjuster {
/** The ordinal. */
private final int ordinal;
/** The day-of-week value, from 1 to 7. */
private final int dowValue;
private DayOfWeekInMonth(int ordinal, DayOfWeek dow) {
super();
this.ordinal = ordinal;
this.dowValue = dow.getValue();
}
@Override
public DateTime doWithAdjustment(DateTime dateTime) {
if (this.ordinal >= 0) {
DateTime temp = dateTime.with(DAY_OF_MONTH, 1);
int curDow = temp.get(DAY_OF_WEEK);
int dowDiff = (this.dowValue - curDow + 7) % 7;
dowDiff += (this.ordinal - 1L) * 7L; // safe from overflow
return temp.plus(dowDiff, DAYS);
} else {
DateTime temp = dateTime.with(DAY_OF_MONTH, dateTime.range(DAY_OF_MONTH).getMaximum());
int curDow = temp.get(DAY_OF_WEEK);
int daysDiff = this.dowValue - curDow;
daysDiff = (daysDiff == 0 ? 0 : (daysDiff > 0 ? daysDiff - 7 : daysDiff));
daysDiff -= (-this.ordinal - 1L) * 7L; // safe from overflow
return temp.plus(daysDiff, DAYS);
}
}
}
// -----------------------------------------------------------------------
/**
* Returns the next day-of-week adjuster, which adjusts the date to the first occurrence of the specified
* day-of-week after the date being adjusted.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 (a Saturday) for parameter (MONDAY) will return 2011-01-17 (two days later).<br />
* The input 2011-01-15 (a Saturday) for parameter (WEDNESDAY) will return 2011-01-19 (four days later).<br />
* The input 2011-01-15 (a Saturday) for parameter (SATURDAY) will return 2011-01-22 (seven days later).
*
* @param dayOfWeek the day-of-week to move the date to, not null
* @return the next day-of-week adjuster, not null
*/
public static WithAdjuster next(DayOfWeek dayOfWeek) {
return new RelativeDayOfWeek(2, dayOfWeek);
}
/**
* Returns the next-or-same day-of-week adjuster, which adjusts the date to the first occurrence of the
* specified day-of-week after the date being adjusted unless it is already on that day in which case the
* same object is returned.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 (a Saturday) for parameter (MONDAY) will return 2011-01-17 (two days later).<br />
* The input 2011-01-15 (a Saturday) for parameter (WEDNESDAY) will return 2011-01-19 (four days later).<br />
* The input 2011-01-15 (a Saturday) for parameter (SATURDAY) will return 2011-01-15 (same as input).
*
* @param dayOfWeek the day-of-week to check for or move the date to, not null
* @return the next-or-same day-of-week adjuster, not null
*/
public static WithAdjuster nextOrSame(DayOfWeek dayOfWeek) {
return new RelativeDayOfWeek(0, dayOfWeek);
}
/**
* Returns the previous day-of-week adjuster, which adjusts the date to the first occurrence of the
* specified day-of-week before the date being adjusted.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 (a Saturday) for parameter (MONDAY) will return 2011-01-10 (five days earlier).<br />
* The input 2011-01-15 (a Saturday) for parameter (WEDNESDAY) will return 2011-01-12 (three days earlier).<br />
* The input 2011-01-15 (a Saturday) for parameter (SATURDAY) will return 2011-01-08 (seven days earlier).
*
* @param dayOfWeek the day-of-week to move the date to, not null
* @return the previous day-of-week adjuster, not null
*/
public static WithAdjuster previous(DayOfWeek dayOfWeek) {
return new RelativeDayOfWeek(3, dayOfWeek);
}
/**
* Returns the previous-or-same day-of-week adjuster, which adjusts the date to the first occurrence of the
* specified day-of-week before the date being adjusted unless it is already on that day in which case the
* same object is returned.
* <p>
* The ISO calendar system behaves as follows:<br />
* The input 2011-01-15 (a Saturday) for parameter (MONDAY) will return 2011-01-10 (five days earlier).<br />
* The input 2011-01-15 (a Saturday) for parameter (WEDNESDAY) will return 2011-01-12 (three days earlier).<br />
* The input 2011-01-15 (a Saturday) for parameter (SATURDAY) will return 2011-01-15 (same as input).
*
* @param dayOfWeek the day-of-week to check for or move the date to, not null
* @return the previous-or-same day-of-week adjuster, not null
*/
public static WithAdjuster previousOrSame(DayOfWeek dayOfWeek) {
return new RelativeDayOfWeek(1, dayOfWeek);
}
/**
* Implementation of next, previous or current day-of-week.
*/
private static final class RelativeDayOfWeek implements WithAdjuster {
/** Whether the current date is a valid answer. */
private final int relative;
/** The day-of-week value, from 1 to 7. */
private final int dowValue;
private RelativeDayOfWeek(int relative, DayOfWeek dayOfWeek) {
Jdk7Methods.Objects_requireNonNull(dayOfWeek, "dayOfWeek");
this.relative = relative;
this.dowValue = dayOfWeek.getValue();
}
@Override
public DateTime doWithAdjustment(DateTime dateTime) {
int calDow = dateTime.get(DAY_OF_WEEK);
if (this.relative < 2 && calDow == this.dowValue) {
return dateTime;
}
if ((this.relative & 1) == 0) {
int daysDiff = calDow - this.dowValue;
return dateTime.plus(daysDiff >= 0 ? 7 - daysDiff : -daysDiff, DAYS);
} else {
int daysDiff = this.dowValue - calDow;
return dateTime.minus(daysDiff >= 0 ? 7 - daysDiff : -daysDiff, DAYS);
}
}
}
}