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

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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.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 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.Temporal;

    71 import java.time.temporal.TemporalAccessor;

    72 import java.time.temporal.TemporalAdjuster;

    73 import java.time.temporal.TemporalField;

    74 import java.time.temporal.TemporalQueries;

    75 import java.time.temporal.TemporalQuery;

    76 import java.time.temporal.UnsupportedTemporalTypeException;

    77 import java.time.temporal.ValueRange;

    78 import java.time.temporal.WeekFields;

    79 import java.util.Locale;

    80 

    81 /**

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

    83  * <p>

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

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

    86  * <p>

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

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

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

    90  * to ensure code clarity.

    91  * <p>

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

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

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

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

    96  * <p>

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

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

    99  * <p>

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

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

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

   103  *

   104  * @implSpec

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

   106  *

   107  * @since 1.8

   108  */

   109 public enum DayOfWeek implements TemporalAccessor, TemporalAdjuster {

   110 

   111     /**

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

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

   114      */

   115     MONDAY,

   116     /**

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

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

   119      */

   120     TUESDAY,

   121     /**

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

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

   124      */

   125     WEDNESDAY,

   126     /**

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

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

   129      */

   130     THURSDAY,

   131     /**

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

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

   134      */

   135     FRIDAY,

   136     /**

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

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

   139      */

   140     SATURDAY,

   141     /**

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

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

   144      */

   145     SUNDAY;

   146     /**

   147      * Private cache of all the constants.

   148      */

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

   150 

   151     //-----------------------------------------------------------------------

   152     /**

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

   154      * <p>

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

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

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

   158      *

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

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

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

   162      */

   163     public static DayOfWeek of(int dayOfWeek) {

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

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

   166         }

   167         return ENUMS[dayOfWeek - 1];

   168     }

   169 

   170     //-----------------------------------------------------------------------

   171     /**

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

   173      * <p>

   174      * This obtains a day-of-week based on the specified temporal.

   175      * A {@code TemporalAccessor} represents an arbitrary set of date and time information,

   176      * which this factory converts to an instance of {@code DayOfWeek}.

   177      * <p>

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

   179      * <p>

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

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

   182      *

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

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

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

   186      */

   187     public static DayOfWeek from(TemporalAccessor temporal) {

   188         if (temporal instanceof DayOfWeek) {

   189             return (DayOfWeek) temporal;

   190         }

   191         try {

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

   193         } catch (DateTimeException ex) {

   194             throw new DateTimeException("Unable to obtain DayOfWeek from TemporalAccessor: " +

   195                     temporal + " of type " + temporal.getClass().getName(), ex);

   196         }

   197     }

   198 

   199     //-----------------------------------------------------------------------

   200     /**

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

   202      * <p>

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

   204      * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week-numbering.

   205      *

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

   207      */

   208     public int getValue() {

   209         return ordinal() + 1;

   210     }

   211 

   212     //-----------------------------------------------------------------------

   213     /**

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

   215      * <p>

   216      * This returns the textual name used to identify the day-of-week,

   217      * suitable for presentation to the user.

   218      * The parameters control the style of the returned text and the locale.

   219      * <p>

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

   221      *

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

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

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

   225      */

   226     public String getDisplayName(TextStyle style, Locale locale) {

   227         return new DateTimeFormatterBuilder().appendText(DAY_OF_WEEK, style).toFormatter(locale).format(this);

   228     }

   229 

   230     //-----------------------------------------------------------------------

   231     /**

   232      * Checks if the specified field is supported.

   233      * <p>

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

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

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

   237      * <p>

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

   239      * this method returns true.

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

   241      * <p>

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

   243      * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}

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

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

   246      *

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

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

   249      */

   250     @Override

   251     public boolean isSupported(TemporalField field) {

   252         if (field instanceof ChronoField) {

   253             return field == DAY_OF_WEEK;

   254         }

   255         return field != null && field.isSupportedBy(this);

   256     }

   257 

   258     /**

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

   260      * <p>

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

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

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

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

   265      * <p>

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

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

   268      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.

   269      * <p>

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

   271      * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}

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

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

   274      *

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

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

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

   278      * @throws UnsupportedTemporalTypeException if the field is not supported

   279      */

   280     @Override

   281     public ValueRange range(TemporalField field) {

   282         if (field == DAY_OF_WEEK) {

   283             return field.range();

   284         }

   285         return TemporalAccessor.super.range(field);

   286     }

   287 

   288     /**

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

   290      * <p>

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

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

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

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

   295      * <p>

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

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

   298      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.

   299      * <p>

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

   301      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}

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

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

   304      *

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

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

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

   308      *         the value is outside the range of valid values for the field

   309      * @throws UnsupportedTemporalTypeException if the field is not supported or

   310      *         the range of values exceeds an {@code int}

   311      * @throws ArithmeticException if numeric overflow occurs

   312      */

   313     @Override

   314     public int get(TemporalField field) {

   315         if (field == DAY_OF_WEEK) {

   316             return getValue();

   317         }

   318         return TemporalAccessor.super.get(field);

   319     }

   320 

   321     /**

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

   323      * <p>

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

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

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

   327      * <p>

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

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

   330      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.

   331      * <p>

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

   333      * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}

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

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

   336      *

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

   338      * @return the value for the field

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

   340      * @throws UnsupportedTemporalTypeException if the field is not supported

   341      * @throws ArithmeticException if numeric overflow occurs

   342      */

   343     @Override

   344     public long getLong(TemporalField field) {

   345         if (field == DAY_OF_WEEK) {

   346             return getValue();

   347         } else if (field instanceof ChronoField) {

   348             throw new UnsupportedTemporalTypeException("Unsupported field: " + field);

   349         }

   350         return field.getFrom(this);

   351     }

   352 

   353     //-----------------------------------------------------------------------

   354     /**

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

   356      * <p>

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

   358      * The specified period may be negative.

   359      * <p>

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

   361      *

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

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

   364      */

   365     public DayOfWeek plus(long days) {

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

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

   368     }

   369 

   370     /**

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

   372      * <p>

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

   374      * The specified period may be negative.

   375      * <p>

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

   377      *

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

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

   380      */

   381     public DayOfWeek minus(long days) {

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

   383     }

   384 

   385     //-----------------------------------------------------------------------

   386     /**

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

   388      * <p>

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

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

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

   392      * what the result of this method will be.

   393      * <p>

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

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

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

   397      *

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

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

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

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

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

   403      */

   404     @SuppressWarnings("unchecked")

   405     @Override

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

   407         if (query == TemporalQueries.precision()) {

   408             return (R) DAYS;

   409         }

   410         return TemporalAccessor.super.query(query);

   411     }

   412 

   413     /**

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

   415      * <p>

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

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

   418      * <p>

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

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

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

   422      * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week start days.

   423      * See {@code TemporalAdjuster} for other adjusters with more control,

   424      * such as {@code next(MONDAY)}.

   425      * <p>

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

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

   428      * <pre>

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

   430      *   temporal = thisDayOfWeek.adjustInto(temporal);

   431      *   temporal = temporal.with(thisDayOfWeek);

   432      * </pre>

   433      * <p>

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

   435      * <pre>

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

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

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

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

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

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

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

   443      * </pre>

   444      * <p>

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

   446      *

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

   448      * @return the adjusted object, not null

   449      * @throws DateTimeException if unable to make the adjustment

   450      * @throws ArithmeticException if numeric overflow occurs

   451      */

   452     @Override

   453     public Temporal adjustInto(Temporal temporal) {

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

   455     }

   456 

   457 }