1 /*

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     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

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     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.

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    25 

    26 /*

    27  * This file is available under and governed by the GNU General Public

    28  * License version 2 only, as published by the Free Software Foundation.

    29  * However, the following notice accompanied the original version of this

    30  * file:

    31  *

    32  * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos

    33  *

    34  * All rights reserved.

    35  *

    36  * Redistribution and use in source and binary forms, with or without

    37  * modification, are permitted provided that the following conditions are met:

    38  *

    39  *  * Redistributions of source code must retain the above copyright notice,

    40  *    this list of conditions and the following disclaimer.

    41  *

    42  *  * Redistributions in binary form must reproduce the above copyright notice,

    43  *    this list of conditions and the following disclaimer in the documentation

    44  *    and/or other materials provided with the distribution.

    45  *

    46  *  * Neither the name of JSR-310 nor the names of its contributors

    47  *    may be used to endorse or promote products derived from this software

    48  *    without specific prior written permission.

    49  *

    50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

    51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

    52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

    53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR

    54  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

    55  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

    56  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

    57  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

    58  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

    59  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

    60  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    61  */

    62 package java.time;

    63 

    64 import static java.time.temporal.ChronoField.DAY_OF_WEEK;

    65 import static java.time.temporal.ChronoUnit.DAYS;

    66 

    67 import java.time.format.DateTimeFormatterBuilder;

    68 import java.time.format.TextStyle;

    69 import java.time.temporal.ChronoField;

    70 import java.time.temporal.Queries;

    71 import java.time.temporal.Temporal;

    72 import java.time.temporal.TemporalAccessor;

    73 import java.time.temporal.TemporalAdjuster;

    74 import java.time.temporal.TemporalField;

    75 import java.time.temporal.TemporalQuery;

    76 import java.time.temporal.ValueRange;

    77 import java.time.temporal.WeekFields;

    78 import java.util.Locale;

    79 

    80 /**

    81  * A day-of-week, such as 'Tuesday'.

    82  * <p>

    83  * {@code DayOfWeek} is an enum representing the 7 days of the week -

    84  * Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday.

    85  * <p>

    86  * In addition to the textual enum name, each day-of-week has an {@code int} value.

    87  * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).

    88  * It is recommended that applications use the enum rather than the {@code int} value

    89  * to ensure code clarity.

    90  * <p>

    91  * This enum provides access to the localized textual form of the day-of-week.

    92  * Some locales also assign different numeric values to the days, declaring

    93  * Sunday to have the value 1, however this class provides no support for this.

    94  * See {@link WeekFields} for localized week-numbering.

    95  * <p>

    96  * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code DayOfWeek}.

    97  * Use {@code getValue()} instead.</b>

    98  * <p>

    99  * This enum represents a common concept that is found in many calendar systems.

   100  * As such, this enum may be used by any calendar system that has the day-of-week

   101  * concept defined exactly equivalent to the ISO calendar system.

   102  *

   103  * <h3>Specification for implementors</h3>

   104  * This is an immutable and thread-safe enum.

   105  *

   106  * @since 1.8

   107  */

   108 public enum DayOfWeek implements TemporalAccessor, TemporalAdjuster {

   109 

   110     /**

   111      * The singleton instance for the day-of-week of Monday.

   112      * This has the numeric value of {@code 1}.

   113      */

   114     MONDAY,

   115     /**

   116      * The singleton instance for the day-of-week of Tuesday.

   117      * This has the numeric value of {@code 2}.

   118      */

   119     TUESDAY,

   120     /**

   121      * The singleton instance for the day-of-week of Wednesday.

   122      * This has the numeric value of {@code 3}.

   123      */

   124     WEDNESDAY,

   125     /**

   126      * The singleton instance for the day-of-week of Thursday.

   127      * This has the numeric value of {@code 4}.

   128      */

   129     THURSDAY,

   130     /**

   131      * The singleton instance for the day-of-week of Friday.

   132      * This has the numeric value of {@code 5}.

   133      */

   134     FRIDAY,

   135     /**

   136      * The singleton instance for the day-of-week of Saturday.

   137      * This has the numeric value of {@code 6}.

   138      */

   139     SATURDAY,

   140     /**

   141      * The singleton instance for the day-of-week of Sunday.

   142      * This has the numeric value of {@code 7}.

   143      */

   144     SUNDAY;

   145     /**

   146      * Private cache of all the constants.

   147      */

   148     private static final DayOfWeek[] ENUMS = DayOfWeek.values();

   149 

   150     //-----------------------------------------------------------------------

   151     /**

   152      * Obtains an instance of {@code DayOfWeek} from an {@code int} value.

   153      * <p>

   154      * {@code DayOfWeek} is an enum representing the 7 days of the week.

   155      * This factory allows the enum to be obtained from the {@code int} value.

   156      * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).

   157      *

   158      * @param dayOfWeek  the day-of-week to represent, from 1 (Monday) to 7 (Sunday)

   159      * @return the day-of-week singleton, not null

   160      * @throws DateTimeException if the day-of-week is invalid

   161      */

   162     public static DayOfWeek of(int dayOfWeek) {

   163         if (dayOfWeek < 1 || dayOfWeek > 7) {

   164             throw new DateTimeException("Invalid value for DayOfWeek: " + dayOfWeek);

   165         }

   166         return ENUMS[dayOfWeek - 1];

   167     }

   168 

   169     //-----------------------------------------------------------------------

   170     /**

   171      * Obtains an instance of {@code DayOfWeek} from a temporal object.

   172      * <p>

   173      * A {@code TemporalAccessor} represents some form of date and time information.

   174      * This factory converts the arbitrary temporal object to an instance of {@code DayOfWeek}.

   175      * <p>

   176      * The conversion extracts the {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} field.

   177      * <p>

   178      * This method matches the signature of the functional interface {@link TemporalQuery}

   179      * allowing it to be used as a query via method reference, {@code DayOfWeek::from}.

   180      *

   181      * @param temporal  the temporal object to convert, not null

   182      * @return the day-of-week, not null

   183      * @throws DateTimeException if unable to convert to a {@code DayOfWeek}

   184      */

   185     public static DayOfWeek from(TemporalAccessor temporal) {

   186         if (temporal instanceof DayOfWeek) {

   187             return (DayOfWeek) temporal;

   188         }

   189         return of(temporal.get(DAY_OF_WEEK));

   190     }

   191 

   192     //-----------------------------------------------------------------------

   193     /**

   194      * Gets the day-of-week {@code int} value.

   195      * <p>

   196      * The values are numbered following the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).

   197      * See {@link WeekFields#dayOfWeek} for localized week-numbering.

   198      *

   199      * @return the day-of-week, from 1 (Monday) to 7 (Sunday)

   200      */

   201     public int getValue() {

   202         return ordinal() + 1;

   203     }

   204 

   205     //-----------------------------------------------------------------------

   206     /**

   207      * Gets the textual representation, such as 'Mon' or 'Friday'.

   208      * <p>

   209      * This returns the textual name used to identify the day-of-week.

   210      * The parameters control the length of the returned text and the locale.

   211      * <p>

   212      * If no textual mapping is found then the {@link #getValue() numeric value} is returned.

   213      *

   214      * @param style  the length of the text required, not null

   215      * @param locale  the locale to use, not null

   216      * @return the text value of the day-of-week, not null

   217      */

   218     public String getText(TextStyle style, Locale locale) {

   219         return new DateTimeFormatterBuilder().appendText(DAY_OF_WEEK, style).toFormatter(locale).print(this);

   220     }

   221 

   222     //-----------------------------------------------------------------------

   223     /**

   224      * Checks if the specified field is supported.

   225      * <p>

   226      * This checks if this day-of-week can be queried for the specified field.

   227      * If false, then calling the {@link #range(TemporalField) range} and

   228      * {@link #get(TemporalField) get} methods will throw an exception.

   229      * <p>

   230      * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then

   231      * this method returns true.

   232      * All other {@code ChronoField} instances will return false.

   233      * <p>

   234      * If the field is not a {@code ChronoField}, then the result of this method

   235      * is obtained by invoking {@code TemporalField.doIsSupported(TemporalAccessor)}

   236      * passing {@code this} as the argument.

   237      * Whether the field is supported is determined by the field.

   238      *

   239      * @param field  the field to check, null returns false

   240      * @return true if the field is supported on this day-of-week, false if not

   241      */

   242     @Override

   243     public boolean isSupported(TemporalField field) {

   244         if (field instanceof ChronoField) {

   245             return field == DAY_OF_WEEK;

   246         }

   247         return field != null && field.doIsSupported(this);

   248     }

   249 

   250     /**

   251      * Gets the range of valid values for the specified field.

   252      * <p>

   253      * The range object expresses the minimum and maximum valid values for a field.

   254      * This day-of-week is used to enhance the accuracy of the returned range.

   255      * If it is not possible to return the range, because the field is not supported

   256      * or for some other reason, an exception is thrown.

   257      * <p>

   258      * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the

   259      * range of the day-of-week, from 1 to 7, will be returned.

   260      * All other {@code ChronoField} instances will throw a {@code DateTimeException}.

   261      * <p>

   262      * If the field is not a {@code ChronoField}, then the result of this method

   263      * is obtained by invoking {@code TemporalField.doRange(TemporalAccessor)}

   264      * passing {@code this} as the argument.

   265      * Whether the range can be obtained is determined by the field.

   266      *

   267      * @param field  the field to query the range for, not null

   268      * @return the range of valid values for the field, not null

   269      * @throws DateTimeException if the range for the field cannot be obtained

   270      */

   271     @Override

   272     public ValueRange range(TemporalField field) {

   273         if (field == DAY_OF_WEEK) {

   274             return field.range();

   275         }

   276         return TemporalAccessor.super.range(field);

   277     }

   278 

   279     /**

   280      * Gets the value of the specified field from this day-of-week as an {@code int}.

   281      * <p>

   282      * This queries this day-of-week for the value for the specified field.

   283      * The returned value will always be within the valid range of values for the field.

   284      * If it is not possible to return the value, because the field is not supported

   285      * or for some other reason, an exception is thrown.

   286      * <p>

   287      * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the

   288      * value of the day-of-week, from 1 to 7, will be returned.

   289      * All other {@code ChronoField} instances will throw a {@code DateTimeException}.

   290      * <p>

   291      * If the field is not a {@code ChronoField}, then the result of this method

   292      * is obtained by invoking {@code TemporalField.doGet(TemporalAccessor)}

   293      * passing {@code this} as the argument. Whether the value can be obtained,

   294      * and what the value represents, is determined by the field.

   295      *

   296      * @param field  the field to get, not null

   297      * @return the value for the field, within the valid range of values

   298      * @throws DateTimeException if a value for the field cannot be obtained

   299      * @throws DateTimeException if the range of valid values for the field exceeds an {@code int}

   300      * @throws DateTimeException if the value is outside the range of valid values for the field

   301      * @throws ArithmeticException if numeric overflow occurs

   302      */

   303     @Override

   304     public int get(TemporalField field) {

   305         if (field == DAY_OF_WEEK) {

   306             return getValue();

   307         }

   308         return TemporalAccessor.super.get(field);

   309     }

   310 

   311     /**

   312      * Gets the value of the specified field from this day-of-week as a {@code long}.

   313      * <p>

   314      * This queries this day-of-week for the value for the specified field.

   315      * If it is not possible to return the value, because the field is not supported

   316      * or for some other reason, an exception is thrown.

   317      * <p>

   318      * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the

   319      * value of the day-of-week, from 1 to 7, will be returned.

   320      * All other {@code ChronoField} instances will throw a {@code DateTimeException}.

   321      * <p>

   322      * If the field is not a {@code ChronoField}, then the result of this method

   323      * is obtained by invoking {@code TemporalField.doGet(TemporalAccessor)}

   324      * passing {@code this} as the argument. Whether the value can be obtained,

   325      * and what the value represents, is determined by the field.

   326      *

   327      * @param field  the field to get, not null

   328      * @return the value for the field

   329      * @throws DateTimeException if a value for the field cannot be obtained

   330      * @throws ArithmeticException if numeric overflow occurs

   331      */

   332     @Override

   333     public long getLong(TemporalField field) {

   334         if (field == DAY_OF_WEEK) {

   335             return getValue();

   336         } else if (field instanceof ChronoField) {

   337             throw new DateTimeException("Unsupported field: " + field.getName());

   338         }

   339         return field.doGet(this);

   340     }

   341 

   342     //-----------------------------------------------------------------------

   343     /**

   344      * Returns the day-of-week that is the specified number of days after this one.

   345      * <p>

   346      * The calculation rolls around the end of the week from Sunday to Monday.

   347      * The specified period may be negative.

   348      * <p>

   349      * This instance is immutable and unaffected by this method call.

   350      *

   351      * @param days  the days to add, positive or negative

   352      * @return the resulting day-of-week, not null

   353      */

   354     public DayOfWeek plus(long days) {

   355         int amount = (int) (days % 7);

   356         return ENUMS[(ordinal() + (amount + 7)) % 7];

   357     }

   358 

   359     /**

   360      * Returns the day-of-week that is the specified number of days before this one.

   361      * <p>

   362      * The calculation rolls around the start of the year from Monday to Sunday.

   363      * The specified period may be negative.

   364      * <p>

   365      * This instance is immutable and unaffected by this method call.

   366      *

   367      * @param days  the days to subtract, positive or negative

   368      * @return the resulting day-of-week, not null

   369      */

   370     public DayOfWeek minus(long days) {

   371         return plus(-(days % 7));

   372     }

   373 

   374     //-----------------------------------------------------------------------

   375     /**

   376      * Queries this day-of-week using the specified query.

   377      * <p>

   378      * This queries this day-of-week using the specified query strategy object.

   379      * The {@code TemporalQuery} object defines the logic to be used to

   380      * obtain the result. Read the documentation of the query to understand

   381      * what the result of this method will be.

   382      * <p>

   383      * The result of this method is obtained by invoking the

   384      * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the

   385      * specified query passing {@code this} as the argument.

   386      *

   387      * @param <R> the type of the result

   388      * @param query  the query to invoke, not null

   389      * @return the query result, null may be returned (defined by the query)

   390      * @throws DateTimeException if unable to query (defined by the query)

   391      * @throws ArithmeticException if numeric overflow occurs (defined by the query)

   392      */

   393     @SuppressWarnings("unchecked")

   394     @Override

   395     public <R> R query(TemporalQuery<R> query) {

   396         if (query == Queries.precision()) {

   397             return (R) DAYS;

   398         }

   399         return TemporalAccessor.super.query(query);

   400     }

   401 

   402     /**

   403      * Adjusts the specified temporal object to have this day-of-week.

   404      * <p>

   405      * This returns a temporal object of the same observable type as the input

   406      * with the day-of-week changed to be the same as this.

   407      * <p>

   408      * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}

   409      * passing {@link ChronoField#DAY_OF_WEEK} as the field.

   410      * Note that this adjusts forwards or backwards within a Monday to Sunday week.

   411      * See {@link WeekFields#dayOfWeek} for localized week start days.

   412      * See {@link java.time.temporal.Adjusters Adjusters} for other adjusters

   413      * with more control, such as {@code next(MONDAY)}.

   414      * <p>

   415      * In most cases, it is clearer to reverse the calling pattern by using

   416      * {@link Temporal#with(TemporalAdjuster)}:

   417      * <pre>

   418      *   // these two lines are equivalent, but the second approach is recommended

   419      *   temporal = thisDayOfWeek.adjustInto(temporal);

   420      *   temporal = temporal.with(thisDayOfWeek);

   421      * </pre>

   422      * <p>

   423      * For example, given a date that is a Wednesday, the following are output:

   424      * <pre>

   425      *   dateOnWed.with(MONDAY);     // two days earlier

   426      *   dateOnWed.with(TUESDAY);    // one day earlier

   427      *   dateOnWed.with(WEDNESDAY);  // same date

   428      *   dateOnWed.with(THURSDAY);   // one day later

   429      *   dateOnWed.with(FRIDAY);     // two days later

   430      *   dateOnWed.with(SATURDAY);   // three days later

   431      *   dateOnWed.with(SUNDAY);     // four days later

   432      * </pre>

   433      * <p>

   434      * This instance is immutable and unaffected by this method call.

   435      *

   436      * @param temporal  the target object to be adjusted, not null

   437      * @return the adjusted object, not null

   438      * @throws DateTimeException if unable to make the adjustment

   439      * @throws ArithmeticException if numeric overflow occurs

   440      */

   441     @Override

   442     public Temporal adjustInto(Temporal temporal) {

   443         return temporal.with(DAY_OF_WEEK, getValue());

   444     }

   445 

   446 }