jdk/src/share/classes/java/time/calendar/ChronoDateImpl.java
changeset 15658 55b829ca2334
parent 15657 c588664d547e
child 15659 e575dab44ff5
equal deleted inserted replaced
15657:c588664d547e 15658:55b829ca2334
     1 /*
       
     2  * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
       
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
       
     4  *
       
     5  * This code is free software; you can redistribute it and/or modify it
       
     6  * under the terms of the GNU General Public License version 2 only, as
       
     7  * published by the Free Software Foundation.  Oracle designates this
       
     8  * particular file as subject to the "Classpath" exception as provided
       
     9  * by Oracle in the LICENSE file that accompanied this code.
       
    10  *
       
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
       
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
       
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
       
    14  * version 2 for more details (a copy is included in the LICENSE file that
       
    15  * accompanied this code).
       
    16  *
       
    17  * You should have received a copy of the GNU General Public License version
       
    18  * 2 along with this work; if not, write to the Free Software Foundation,
       
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
       
    20  *
       
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
       
    22  * or visit www.oracle.com if you need additional information or have any
       
    23  * questions.
       
    24  */
       
    25 
       
    26 /*
       
    27  * Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos
       
    28  *
       
    29  * All rights reserved.
       
    30  *
       
    31  * Redistribution and use in source and binary forms, with or without
       
    32  * modification, are permitted provided that the following conditions are met:
       
    33  *
       
    34  *  * Redistributions of source code must retain the above copyright notice,
       
    35  *    this list of conditions and the following disclaimer.
       
    36  *
       
    37  *  * Redistributions in binary form must reproduce the above copyright notice,
       
    38  *    this list of conditions and the following disclaimer in the documentation
       
    39  *    and/or other materials provided with the distribution.
       
    40  *
       
    41  *  * Neither the name of JSR-310 nor the names of its contributors
       
    42  *    may be used to endorse or promote products derived from this software
       
    43  *    without specific prior written permission.
       
    44  *
       
    45  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
       
    46  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
       
    47  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
       
    48  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
       
    49  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
       
    50  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
       
    51  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
       
    52  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
       
    53  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
       
    54  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
       
    55  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
       
    56  */
       
    57 package java.time.calendar;
       
    58 
       
    59 import static java.time.temporal.ChronoField.DAY_OF_MONTH;
       
    60 import static java.time.temporal.ChronoField.ERA;
       
    61 import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
       
    62 import static java.time.temporal.ChronoField.YEAR_OF_ERA;
       
    63 
       
    64 import java.io.Serializable;
       
    65 import java.time.DateTimeException;
       
    66 import java.time.LocalDate;
       
    67 import java.time.LocalTime;
       
    68 import java.time.temporal.Chrono;
       
    69 import java.time.temporal.ChronoLocalDate;
       
    70 import java.time.temporal.ChronoLocalDateTime;
       
    71 import java.time.temporal.ChronoUnit;
       
    72 import java.time.temporal.Temporal;
       
    73 import java.time.temporal.TemporalAdjuster;
       
    74 import java.time.temporal.TemporalUnit;
       
    75 
       
    76 /**
       
    77  * A date expressed in terms of a standard year-month-day calendar system.
       
    78  * <p>
       
    79  * This class is used by applications seeking to handle dates in non-ISO calendar systems.
       
    80  * For example, the Japanese, Minguo, Thai Buddhist and others.
       
    81  * <p>
       
    82  * {@code ChronoLocalDate} is built on the generic concepts of year, month and day.
       
    83  * The calendar system, represented by a {@link java.time.temporal.Chrono}, expresses the relationship between
       
    84  * the fields and this class allows the resulting date to be manipulated.
       
    85  * <p>
       
    86  * Note that not all calendar systems are suitable for use with this class.
       
    87  * For example, the Mayan calendar uses a system that bears no relation to years, months and days.
       
    88  * <p>
       
    89  * The API design encourages the use of {@code LocalDate} for the majority of the application.
       
    90  * This includes code to read and write from a persistent data store, such as a database,
       
    91  * and to send dates and times across a network. The {@code ChronoLocalDate} instance is then used
       
    92  * at the user interface level to deal with localized input/output.
       
    93  *
       
    94  * <P>Example: </p>
       
    95  * <pre>
       
    96  *        System.out.printf("Example()%n");
       
    97  *        // Enumerate the list of available calendars and print today for each
       
    98  *        Set&lt;Chrono&gt; chronos = Chrono.getAvailableChronologies();
       
    99  *        for (Chrono chrono : chronos) {
       
   100  *            ChronoLocalDate<?> date = chrono.dateNow();
       
   101  *            System.out.printf("   %20s: %s%n", chrono.getID(), date.toString());
       
   102  *        }
       
   103  *
       
   104  *        // Print the Hijrah date and calendar
       
   105  *        ChronoLocalDate<?> date = Chrono.of("Hijrah").dateNow();
       
   106  *        int day = date.get(ChronoField.DAY_OF_MONTH);
       
   107  *        int dow = date.get(ChronoField.DAY_OF_WEEK);
       
   108  *        int month = date.get(ChronoField.MONTH_OF_YEAR);
       
   109  *        int year = date.get(ChronoField.YEAR);
       
   110  *        System.out.printf("  Today is %s %s %d-%s-%d%n", date.getChrono().getID(),
       
   111  *                dow, day, month, year);
       
   112 
       
   113  *        // Print today's date and the last day of the year
       
   114  *        ChronoLocalDate<?> now1 = Chrono.of("Hijrah").dateNow();
       
   115  *        ChronoLocalDate<?> first = now1.with(ChronoField.DAY_OF_MONTH, 1)
       
   116  *                .with(ChronoField.MONTH_OF_YEAR, 1);
       
   117  *        ChronoLocalDate<?> last = first.plus(1, ChronoUnit.YEARS)
       
   118  *                .minus(1, ChronoUnit.DAYS);
       
   119  *        System.out.printf("  Today is %s: start: %s; end: %s%n", last.getChrono().getID(),
       
   120  *                first, last);
       
   121  * </pre>
       
   122  *
       
   123  * <h3>Adding Calendars</h3>
       
   124  * <p> The set of calendars is extensible by defining a subclass of {@link ChronoLocalDate}
       
   125  * to represent a date instance and an implementation of {@code Chrono}
       
   126  * to be the factory for the ChronoLocalDate subclass.
       
   127  * </p>
       
   128  * <p> To permit the discovery of the additional calendar types the implementation of
       
   129  * {@code Chrono} must be registered as a Service implementing the {@code Chrono} interface
       
   130  * in the {@code META-INF/Services} file as per the specification of {@link java.util.ServiceLoader}.
       
   131  * The subclass must function according to the {@code Chrono} class description and must provide its
       
   132  * {@link java.time.temporal.Chrono#getId() chronlogy ID} and {@link Chrono#getCalendarType() calendar type}. </p>
       
   133  *
       
   134  * <h3>Specification for implementors</h3>
       
   135  * This abstract class must be implemented with care to ensure other classes operate correctly.
       
   136  * All implementations that can be instantiated must be final, immutable and thread-safe.
       
   137  * Subclasses should be Serializable wherever possible.
       
   138  *
       
   139  * @param <C> the chronology of this date
       
   140  * @since 1.8
       
   141  */
       
   142 abstract class ChronoDateImpl<C extends Chrono<C>>
       
   143         implements ChronoLocalDate<C>, Temporal, TemporalAdjuster, Serializable {
       
   144 
       
   145     /**
       
   146      * Serialization version.
       
   147      */
       
   148     private static final long serialVersionUID = 6282433883239719096L;
       
   149 
       
   150     /**
       
   151      * Creates an instance.
       
   152      */
       
   153     ChronoDateImpl() {
       
   154     }
       
   155 
       
   156     //-----------------------------------------------------------------------
       
   157     @Override
       
   158     public ChronoLocalDate<C> plus(long amountToAdd, TemporalUnit unit) {
       
   159         if (unit instanceof ChronoUnit) {
       
   160             ChronoUnit f = (ChronoUnit) unit;
       
   161             switch (f) {
       
   162                 case DAYS: return plusDays(amountToAdd);
       
   163                 case WEEKS: return plusDays(Math.multiplyExact(amountToAdd, 7));
       
   164                 case MONTHS: return plusMonths(amountToAdd);
       
   165                 case YEARS: return plusYears(amountToAdd);
       
   166                 case DECADES: return plusYears(Math.multiplyExact(amountToAdd, 10));
       
   167                 case CENTURIES: return plusYears(Math.multiplyExact(amountToAdd, 100));
       
   168                 case MILLENNIA: return plusYears(Math.multiplyExact(amountToAdd, 1000));
       
   169                 case ERAS: return with(ERA, Math.addExact(getLong(ERA), amountToAdd));
       
   170             }
       
   171             throw new DateTimeException("Unsupported unit: " + unit.getName());
       
   172         }
       
   173         return ChronoLocalDate.super.plus(amountToAdd, unit);
       
   174     }
       
   175 
       
   176     //-----------------------------------------------------------------------
       
   177     /**
       
   178      * Returns a copy of this date with the specified period in years added.
       
   179      * <p>
       
   180      * This adds the specified period in years to the date.
       
   181      * In some cases, adding years can cause the resulting date to become invalid.
       
   182      * If this occurs, then other fields, typically the day-of-month, will be adjusted to ensure
       
   183      * that the result is valid. Typically this will select the last valid day of the month.
       
   184      * <p>
       
   185      * This instance is immutable and unaffected by this method call.
       
   186      *
       
   187      * @param yearsToAdd  the years to add, may be negative
       
   188      * @return a date based on this one with the years added, not null
       
   189      * @throws DateTimeException if the result exceeds the supported date range
       
   190      */
       
   191     abstract ChronoDateImpl<C> plusYears(long yearsToAdd);
       
   192 
       
   193     /**
       
   194      * Returns a copy of this date with the specified period in months added.
       
   195      * <p>
       
   196      * This adds the specified period in months to the date.
       
   197      * In some cases, adding months can cause the resulting date to become invalid.
       
   198      * If this occurs, then other fields, typically the day-of-month, will be adjusted to ensure
       
   199      * that the result is valid. Typically this will select the last valid day of the month.
       
   200      * <p>
       
   201      * This instance is immutable and unaffected by this method call.
       
   202      *
       
   203      * @param monthsToAdd  the months to add, may be negative
       
   204      * @return a date based on this one with the months added, not null
       
   205      * @throws DateTimeException if the result exceeds the supported date range
       
   206      */
       
   207     abstract ChronoDateImpl<C> plusMonths(long monthsToAdd);
       
   208 
       
   209     /**
       
   210      * Returns a copy of this date with the specified period in weeks added.
       
   211      * <p>
       
   212      * This adds the specified period in weeks to the date.
       
   213      * In some cases, adding weeks can cause the resulting date to become invalid.
       
   214      * If this occurs, then other fields will be adjusted to ensure that the result is valid.
       
   215      * <p>
       
   216      * The default implementation uses {@link #plusDays(long)} using a 7 day week.
       
   217      * <p>
       
   218      * This instance is immutable and unaffected by this method call.
       
   219      *
       
   220      * @param weeksToAdd  the weeks to add, may be negative
       
   221      * @return a date based on this one with the weeks added, not null
       
   222      * @throws DateTimeException if the result exceeds the supported date range
       
   223      */
       
   224     ChronoDateImpl<C> plusWeeks(long weeksToAdd) {
       
   225         return plusDays(Math.multiplyExact(weeksToAdd, 7));
       
   226     }
       
   227 
       
   228     /**
       
   229      * Returns a copy of this date with the specified number of days added.
       
   230      * <p>
       
   231      * This adds the specified period in days to the date.
       
   232      * <p>
       
   233      * This instance is immutable and unaffected by this method call.
       
   234      *
       
   235      * @param daysToAdd  the days to add, may be negative
       
   236      * @return a date based on this one with the days added, not null
       
   237      * @throws DateTimeException if the result exceeds the supported date range
       
   238      */
       
   239     abstract ChronoDateImpl<C> plusDays(long daysToAdd);
       
   240 
       
   241     //-----------------------------------------------------------------------
       
   242     /**
       
   243      * Returns a copy of this date with the specified period in years subtracted.
       
   244      * <p>
       
   245      * This subtracts the specified period in years to the date.
       
   246      * In some cases, subtracting years can cause the resulting date to become invalid.
       
   247      * If this occurs, then other fields, typically the day-of-month, will be adjusted to ensure
       
   248      * that the result is valid. Typically this will select the last valid day of the month.
       
   249      * <p>
       
   250      * The default implementation uses {@link #plusYears(long)}.
       
   251      * <p>
       
   252      * This instance is immutable and unaffected by this method call.
       
   253      *
       
   254      * @param yearsToSubtract  the years to subtract, may be negative
       
   255      * @return a date based on this one with the years subtracted, not null
       
   256      * @throws DateTimeException if the result exceeds the supported date range
       
   257      */
       
   258     ChronoDateImpl<C> minusYears(long yearsToSubtract) {
       
   259         return (yearsToSubtract == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-yearsToSubtract));
       
   260     }
       
   261 
       
   262     /**
       
   263      * Returns a copy of this date with the specified period in months subtracted.
       
   264      * <p>
       
   265      * This subtracts the specified period in months to the date.
       
   266      * In some cases, subtracting months can cause the resulting date to become invalid.
       
   267      * If this occurs, then other fields, typically the day-of-month, will be adjusted to ensure
       
   268      * that the result is valid. Typically this will select the last valid day of the month.
       
   269      * <p>
       
   270      * The default implementation uses {@link #plusMonths(long)}.
       
   271      * <p>
       
   272      * This instance is immutable and unaffected by this method call.
       
   273      *
       
   274      * @param monthsToSubtract  the months to subtract, may be negative
       
   275      * @return a date based on this one with the months subtracted, not null
       
   276      * @throws DateTimeException if the result exceeds the supported date range
       
   277      */
       
   278     ChronoDateImpl<C> minusMonths(long monthsToSubtract) {
       
   279         return (monthsToSubtract == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-monthsToSubtract));
       
   280     }
       
   281 
       
   282     /**
       
   283      * Returns a copy of this date with the specified period in weeks subtracted.
       
   284      * <p>
       
   285      * This subtracts the specified period in weeks to the date.
       
   286      * In some cases, subtracting weeks can cause the resulting date to become invalid.
       
   287      * If this occurs, then other fields will be adjusted to ensure that the result is valid.
       
   288      * <p>
       
   289      * The default implementation uses {@link #plusWeeks(long)}.
       
   290      * <p>
       
   291      * This instance is immutable and unaffected by this method call.
       
   292      *
       
   293      * @param weeksToSubtract  the weeks to subtract, may be negative
       
   294      * @return a date based on this one with the weeks subtracted, not null
       
   295      * @throws DateTimeException if the result exceeds the supported date range
       
   296      */
       
   297     ChronoDateImpl<C> minusWeeks(long weeksToSubtract) {
       
   298         return (weeksToSubtract == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeksToSubtract));
       
   299     }
       
   300 
       
   301     /**
       
   302      * Returns a copy of this date with the specified number of days subtracted.
       
   303      * <p>
       
   304      * This subtracts the specified period in days to the date.
       
   305      * <p>
       
   306      * The default implementation uses {@link #plusDays(long)}.
       
   307      * <p>
       
   308      * This instance is immutable and unaffected by this method call.
       
   309      *
       
   310      * @param daysToSubtract  the days to subtract, may be negative
       
   311      * @return a date based on this one with the days subtracted, not null
       
   312      * @throws DateTimeException if the result exceeds the supported date range
       
   313      */
       
   314     ChronoDateImpl<C> minusDays(long daysToSubtract) {
       
   315         return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
       
   316     }
       
   317 
       
   318     @Override
       
   319     public final ChronoLocalDateTime<C> atTime(LocalTime localTime) {
       
   320         return Chrono.dateTime(this, localTime);
       
   321     }
       
   322 
       
   323     //-----------------------------------------------------------------------
       
   324     /**
       
   325      * {@inheritDoc}
       
   326      * @throws DateTimeException {@inheritDoc}
       
   327      * @throws ArithmeticException {@inheritDoc}
       
   328      */
       
   329     @Override
       
   330     public long periodUntil(Temporal endDateTime, TemporalUnit unit) {
       
   331         if (endDateTime instanceof ChronoLocalDate == false) {
       
   332             throw new DateTimeException("Unable to calculate period between objects of two different types");
       
   333         }
       
   334         ChronoLocalDate<?> end = (ChronoLocalDate<?>) endDateTime;
       
   335         if (getChrono().equals(end.getChrono()) == false) {
       
   336             throw new DateTimeException("Unable to calculate period between two different chronologies");
       
   337         }
       
   338         if (unit instanceof ChronoUnit) {
       
   339             return LocalDate.from(this).periodUntil(end, unit);  // TODO: this is wrong
       
   340         }
       
   341         return unit.between(this, endDateTime).getAmount();
       
   342     }
       
   343 
       
   344     @Override
       
   345     public boolean equals(Object obj) {
       
   346         if (this == obj) {
       
   347             return true;
       
   348         }
       
   349         if (obj instanceof ChronoLocalDate) {
       
   350             return compareTo((ChronoLocalDate<?>) obj) == 0;
       
   351         }
       
   352         return false;
       
   353     }
       
   354 
       
   355     @Override
       
   356     public int hashCode() {
       
   357         long epDay = toEpochDay();
       
   358         return getChrono().hashCode() ^ ((int) (epDay ^ (epDay >>> 32)));
       
   359     }
       
   360 
       
   361     @Override
       
   362     public String toString() {
       
   363         // getLong() reduces chances of exceptions in toString()
       
   364         long yoe = getLong(YEAR_OF_ERA);
       
   365         long moy = getLong(MONTH_OF_YEAR);
       
   366         long dom = getLong(DAY_OF_MONTH);
       
   367         StringBuilder buf = new StringBuilder(30);
       
   368         buf.append(getChrono().toString())
       
   369                 .append(" ")
       
   370                 .append(getEra())
       
   371                 .append(" ")
       
   372                 .append(yoe)
       
   373                 .append(moy < 10 ? "-0" : "-").append(moy)
       
   374                 .append(dom < 10 ? "-0" : "-").append(dom);
       
   375         return buf.toString();
       
   376     }
       
   377 
       
   378 }