/* * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file: * * Copyright (c) 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 java.time.chrono; import java.time.DateTimeException; import java.time.temporal.ChronoUnit; import java.time.temporal.Temporal; import java.time.temporal.TemporalAmount; import java.time.temporal.TemporalUnit; import java.time.temporal.UnsupportedTemporalTypeException; import java.util.List; import java.util.Objects; /** * A date-based amount of time, such as '3 years, 4 months and 5 days' in an * arbitrary chronology, intended for advanced globalization use cases. *

* This interface models a date-based amount of time in a calendar system. * While most calendar systems use years, months and days, some do not. * Therefore, this interface operates solely in terms of a set of supported * units that are defined by the {@code Chronology}. * The set of supported units is fixed for a given chronology. * The amount of a supported unit may be set to zero. *

* The period is modeled as a directed amount of time, meaning that individual * parts of the period may be negative. * * @implSpec * This interface must be implemented with care to ensure other classes operate correctly. * All implementations that can be instantiated must be final, immutable and thread-safe. * Subclasses should be Serializable wherever possible. * * @since 1.8 */ public interface ChronoPeriod extends TemporalAmount { /** * Obtains a {@code ChronoPeriod} consisting of amount of time between two dates. *

* The start date is included, but the end date is not. * The period is calculated using {@link ChronoLocalDate#until(ChronoLocalDate)}. * As such, the calculation is chronology specific. *

* The chronology of the first date is used. * The chronology of the second date is ignored, with the date being converted * to the target chronology system before the calculation starts. *

* The result of this method can be a negative period if the end is before the start. * In most cases, the positive/negative sign will be the same in each of the supported fields. * * @param startDateInclusive the start date, inclusive, specifying the chronology of the calculation, not null * @param endDateExclusive the end date, exclusive, in any chronology, not null * @return the period between this date and the end date, not null * @see ChronoLocalDate#until(ChronoLocalDate) */ public static ChronoPeriod between(ChronoLocalDate startDateInclusive, ChronoLocalDate endDateExclusive) { Objects.requireNonNull(startDateInclusive, "startDateInclusive"); Objects.requireNonNull(endDateExclusive, "endDateExclusive"); return startDateInclusive.until(endDateExclusive); } //----------------------------------------------------------------------- /** * Gets the value of the requested unit. *

* The supported units are chronology specific. * They will typically be {@link ChronoUnit#YEARS YEARS}, * {@link ChronoUnit#MONTHS MONTHS} and {@link ChronoUnit#DAYS DAYS}. * Requesting an unsupported unit will throw an exception. * * @param unit the {@code TemporalUnit} for which to return the value * @return the long value of the unit * @throws DateTimeException if the unit is not supported * @throws UnsupportedTemporalTypeException if the unit is not supported */ @Override long get(TemporalUnit unit); /** * Gets the set of units supported by this period. *

* The supported units are chronology specific. * They will typically be {@link ChronoUnit#YEARS YEARS}, * {@link ChronoUnit#MONTHS MONTHS} and {@link ChronoUnit#DAYS DAYS}. * They are returned in order from largest to smallest. *

* This set can be used in conjunction with {@link #get(TemporalUnit)} * to access the entire state of the period. * * @return a list containing the supported units, not null */ @Override List getUnits(); /** * Gets the chronology that defines the meaning of the supported units. *

* The period is defined by the chronology. * It controls the supported units and restricts addition/subtraction * to {@code ChronoLocalDate} instances of the same chronology. * * @return the chronology defining the period, not null */ Chronology getChronology(); //----------------------------------------------------------------------- /** * Checks if all the supported units of this period are zero. * * @return true if this period is zero-length */ default boolean isZero() { for (TemporalUnit unit : getUnits()) { if (get(unit) != 0) { return false; } } return true; } /** * Checks if any of the supported units of this period are negative. * * @return true if any unit of this period is negative */ default boolean isNegative() { for (TemporalUnit unit : getUnits()) { if (get(unit) < 0) { return true; } } return false; } //----------------------------------------------------------------------- /** * Returns a copy of this period with the specified period added. *

* If the specified amount is a {@code ChronoPeriod} then it must have * the same chronology as this period. Implementations may choose to * accept or reject other {@code TemporalAmount} implementations. *

* This instance is immutable and unaffected by this method call. * * @param amountToAdd the period to add, not null * @return a {@code ChronoPeriod} based on this period with the requested period added, not null * @throws ArithmeticException if numeric overflow occurs */ ChronoPeriod plus(TemporalAmount amountToAdd); /** * Returns a copy of this period with the specified period subtracted. *

* If the specified amount is a {@code ChronoPeriod} then it must have * the same chronology as this period. Implementations may choose to * accept or reject other {@code TemporalAmount} implementations. *

* This instance is immutable and unaffected by this method call. * * @param amountToSubtract the period to subtract, not null * @return a {@code ChronoPeriod} based on this period with the requested period subtracted, not null * @throws ArithmeticException if numeric overflow occurs */ ChronoPeriod minus(TemporalAmount amountToSubtract); //----------------------------------------------------------------------- /** * Returns a new instance with each amount in this period in this period * multiplied by the specified scalar. *

* This returns a period with each supported unit individually multiplied. * For example, a period of "2 years, -3 months and 4 days" multiplied by * 3 will return "6 years, -9 months and 12 days". * No normalization is performed. * * @param scalar the scalar to multiply by, not null * @return a {@code ChronoPeriod} based on this period with the amounts multiplied * by the scalar, not null * @throws ArithmeticException if numeric overflow occurs */ ChronoPeriod multipliedBy(int scalar); /** * Returns a new instance with each amount in this period negated. *

* This returns a period with each supported unit individually negated. * For example, a period of "2 years, -3 months and 4 days" will be * negated to "-2 years, 3 months and -4 days". * No normalization is performed. * * @return a {@code ChronoPeriod} based on this period with the amounts negated, not null * @throws ArithmeticException if numeric overflow occurs, which only happens if * one of the units has the value {@code Long.MIN_VALUE} */ default ChronoPeriod negated() { return multipliedBy(-1); } //----------------------------------------------------------------------- /** * Returns a copy of this period with the amounts of each unit normalized. *

* The process of normalization is specific to each calendar system. * For example, in the ISO calendar system, the years and months are * normalized but the days are not, such that "15 months" would be * normalized to "1 year and 3 months". *

* This instance is immutable and unaffected by this method call. * * @return a {@code ChronoPeriod} based on this period with the amounts of each * unit normalized, not null * @throws ArithmeticException if numeric overflow occurs */ ChronoPeriod normalized(); //------------------------------------------------------------------------- /** * Adds this period to the specified temporal object. *

* This returns a temporal object of the same observable type as the input * with this period added. *

* In most cases, it is clearer to reverse the calling pattern by using * {@link Temporal#plus(TemporalAmount)}. *

     *   // these two lines are equivalent, but the second approach is recommended
     *   dateTime = thisPeriod.addTo(dateTime);
     *   dateTime = dateTime.plus(thisPeriod);
     * 
*

* The specified temporal must have the same chronology as this period. * This returns a temporal with the non-zero supported units added. *

* This instance is immutable and unaffected by this method call. * * @param temporal the temporal object to adjust, not null * @return an object of the same type with the adjustment made, not null * @throws DateTimeException if unable to add * @throws ArithmeticException if numeric overflow occurs */ @Override Temporal addTo(Temporal temporal); /** * Subtracts this period from the specified temporal object. *

* This returns a temporal object of the same observable type as the input * with this period subtracted. *

* In most cases, it is clearer to reverse the calling pattern by using * {@link Temporal#minus(TemporalAmount)}. *

     *   // these two lines are equivalent, but the second approach is recommended
     *   dateTime = thisPeriod.subtractFrom(dateTime);
     *   dateTime = dateTime.minus(thisPeriod);
     * 
*

* The specified temporal must have the same chronology as this period. * This returns a temporal with the non-zero supported units subtracted. *

* This instance is immutable and unaffected by this method call. * * @param temporal the temporal object to adjust, not null * @return an object of the same type with the adjustment made, not null * @throws DateTimeException if unable to subtract * @throws ArithmeticException if numeric overflow occurs */ @Override Temporal subtractFrom(Temporal temporal); //----------------------------------------------------------------------- /** * Checks if this period is equal to another period, including the chronology. *

* Compares this period with another ensuring that the type, each amount and * the chronology are the same. * Note that this means that a period of "15 Months" is not equal to a period * of "1 Year and 3 Months". * * @param obj the object to check, null returns false * @return true if this is equal to the other period */ @Override boolean equals(Object obj); /** * A hash code for this period. * * @return a suitable hash code */ @Override int hashCode(); //----------------------------------------------------------------------- /** * Outputs this period as a {@code String}. *

* The output will include the period amounts and chronology. * * @return a string representation of this period, not null */ @Override String toString(); }