Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 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 | * 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.MONTH_OF_YEAR; |
| 65 | import static java.time.temporal.ChronoUnit.MONTHS; |
| 66 | |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 67 | import java.time.chrono.Chronology; |
| 68 | import java.time.chrono.IsoChronology; |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 69 | import java.time.format.DateTimeFormatterBuilder; |
| 70 | import java.time.format.TextStyle; |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 71 | import java.time.temporal.ChronoField; |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 72 | import java.time.temporal.Queries; |
| 73 | import java.time.temporal.Temporal; |
| 74 | import java.time.temporal.TemporalAccessor; |
| 75 | import java.time.temporal.TemporalAdjuster; |
| 76 | import java.time.temporal.TemporalField; |
| 77 | import java.time.temporal.TemporalQuery; |
| 78 | import java.time.temporal.ValueRange; |
| 79 | import java.util.Locale; |
| 80 | |
| 81 | /** |
| 82 | * A month-of-year, such as 'July'. |
| 83 | * <p> |
| 84 | * {@code Month} is an enum representing the 12 months of the year - |
| 85 | * January, February, March, April, May, June, July, August, September, October, |
| 86 | * November and December. |
| 87 | * <p> |
| 88 | * In addition to the textual enum name, each month-of-year has an {@code int} value. |
| 89 | * The {@code int} value follows normal usage and the ISO-8601 standard, |
| 90 | * from 1 (January) to 12 (December). It is recommended that applications use the enum |
| 91 | * rather than the {@code int} value to ensure code clarity. |
| 92 | * <p> |
| 93 | * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code Month}. |
| 94 | * Use {@code getValue()} instead.</b> |
| 95 | * <p> |
| 96 | * This enum represents a common concept that is found in many calendar systems. |
| 97 | * As such, this enum may be used by any calendar system that has the month-of-year |
| 98 | * concept defined exactly equivalent to the ISO-8601 calendar system. |
| 99 | * |
| 100 | * <h3>Specification for implementors</h3> |
| 101 | * This is an immutable and thread-safe enum. |
| 102 | * |
| 103 | * @since 1.8 |
| 104 | */ |
| 105 | public enum Month implements TemporalAccessor, TemporalAdjuster { |
| 106 | |
| 107 | /** |
| 108 | * The singleton instance for the month of January with 31 days. |
| 109 | * This has the numeric value of {@code 1}. |
| 110 | */ |
| 111 | JANUARY, |
| 112 | /** |
| 113 | * The singleton instance for the month of February with 28 days, or 29 in a leap year. |
| 114 | * This has the numeric value of {@code 2}. |
| 115 | */ |
| 116 | FEBRUARY, |
| 117 | /** |
| 118 | * The singleton instance for the month of March with 31 days. |
| 119 | * This has the numeric value of {@code 3}. |
| 120 | */ |
| 121 | MARCH, |
| 122 | /** |
| 123 | * The singleton instance for the month of April with 30 days. |
| 124 | * This has the numeric value of {@code 4}. |
| 125 | */ |
| 126 | APRIL, |
| 127 | /** |
| 128 | * The singleton instance for the month of May with 31 days. |
| 129 | * This has the numeric value of {@code 5}. |
| 130 | */ |
| 131 | MAY, |
| 132 | /** |
| 133 | * The singleton instance for the month of June with 30 days. |
| 134 | * This has the numeric value of {@code 6}. |
| 135 | */ |
| 136 | JUNE, |
| 137 | /** |
| 138 | * The singleton instance for the month of July with 31 days. |
| 139 | * This has the numeric value of {@code 7}. |
| 140 | */ |
| 141 | JULY, |
| 142 | /** |
| 143 | * The singleton instance for the month of August with 31 days. |
| 144 | * This has the numeric value of {@code 8}. |
| 145 | */ |
| 146 | AUGUST, |
| 147 | /** |
| 148 | * The singleton instance for the month of September with 30 days. |
| 149 | * This has the numeric value of {@code 9}. |
| 150 | */ |
| 151 | SEPTEMBER, |
| 152 | /** |
| 153 | * The singleton instance for the month of October with 31 days. |
| 154 | * This has the numeric value of {@code 10}. |
| 155 | */ |
| 156 | OCTOBER, |
| 157 | /** |
| 158 | * The singleton instance for the month of November with 30 days. |
| 159 | * This has the numeric value of {@code 11}. |
| 160 | */ |
| 161 | NOVEMBER, |
| 162 | /** |
| 163 | * The singleton instance for the month of December with 31 days. |
| 164 | * This has the numeric value of {@code 12}. |
| 165 | */ |
| 166 | DECEMBER; |
| 167 | /** |
| 168 | * Private cache of all the constants. |
| 169 | */ |
| 170 | private static final Month[] ENUMS = Month.values(); |
| 171 | |
| 172 | //----------------------------------------------------------------------- |
| 173 | /** |
| 174 | * Obtains an instance of {@code Month} from an {@code int} value. |
| 175 | * <p> |
| 176 | * {@code Month} is an enum representing the 12 months of the year. |
| 177 | * This factory allows the enum to be obtained from the {@code int} value. |
| 178 | * The {@code int} value follows the ISO-8601 standard, from 1 (January) to 12 (December). |
| 179 | * |
| 180 | * @param month the month-of-year to represent, from 1 (January) to 12 (December) |
| 181 | * @return the month-of-year, not null |
| 182 | * @throws DateTimeException if the month-of-year is invalid |
| 183 | */ |
| 184 | public static Month of(int month) { |
| 185 | if (month < 1 || month > 12) { |
| 186 | throw new DateTimeException("Invalid value for MonthOfYear: " + month); |
| 187 | } |
| 188 | return ENUMS[month - 1]; |
| 189 | } |
| 190 | |
| 191 | //----------------------------------------------------------------------- |
| 192 | /** |
| 193 | * Obtains an instance of {@code Month} from a temporal object. |
| 194 | * <p> |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 195 | * This obtains a month based on the specified temporal. |
| 196 | * A {@code TemporalAccessor} represents an arbitrary set of date and time information, |
| 197 | * which this factory converts to an instance of {@code Month}. |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 198 | * <p> |
| 199 | * The conversion extracts the {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} field. |
| 200 | * The extraction is only permitted if the temporal object has an ISO |
| 201 | * chronology, or can be converted to a {@code LocalDate}. |
| 202 | * <p> |
| 203 | * This method matches the signature of the functional interface {@link TemporalQuery} |
| 204 | * allowing it to be used in queries via method reference, {@code Month::from}. |
| 205 | * |
| 206 | * @param temporal the temporal object to convert, not null |
| 207 | * @return the month-of-year, not null |
| 208 | * @throws DateTimeException if unable to convert to a {@code Month} |
| 209 | */ |
| 210 | public static Month from(TemporalAccessor temporal) { |
| 211 | if (temporal instanceof Month) { |
| 212 | return (Month) temporal; |
| 213 | } |
| 214 | try { |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 215 | if (IsoChronology.INSTANCE.equals(Chronology.from(temporal)) == false) { |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 216 | temporal = LocalDate.from(temporal); |
| 217 | } |
| 218 | return of(temporal.get(MONTH_OF_YEAR)); |
| 219 | } catch (DateTimeException ex) { |
| 220 | throw new DateTimeException("Unable to obtain Month from TemporalAccessor: " + temporal.getClass(), ex); |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | //----------------------------------------------------------------------- |
| 225 | /** |
| 226 | * Gets the month-of-year {@code int} value. |
| 227 | * <p> |
| 228 | * The values are numbered following the ISO-8601 standard, |
| 229 | * from 1 (January) to 12 (December). |
| 230 | * |
| 231 | * @return the month-of-year, from 1 (January) to 12 (December) |
| 232 | */ |
| 233 | public int getValue() { |
| 234 | return ordinal() + 1; |
| 235 | } |
| 236 | |
| 237 | //----------------------------------------------------------------------- |
| 238 | /** |
| 239 | * Gets the textual representation, such as 'Jan' or 'December'. |
| 240 | * <p> |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 241 | * This returns the textual name used to identify the month-of-year, |
| 242 | * suitable for presentation to the user. |
| 243 | * The parameters control the style of the returned text and the locale. |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 244 | * <p> |
| 245 | * If no textual mapping is found then the {@link #getValue() numeric value} is returned. |
| 246 | * |
| 247 | * @param style the length of the text required, not null |
| 248 | * @param locale the locale to use, not null |
| 249 | * @return the text value of the month-of-year, not null |
| 250 | */ |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 251 | public String getDisplayName(TextStyle style, Locale locale) { |
| 252 | return new DateTimeFormatterBuilder().appendText(MONTH_OF_YEAR, style).toFormatter(locale).format(this); |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 253 | } |
| 254 | |
| 255 | //----------------------------------------------------------------------- |
| 256 | /** |
| 257 | * Checks if the specified field is supported. |
| 258 | * <p> |
| 259 | * This checks if this month-of-year can be queried for the specified field. |
| 260 | * If false, then calling the {@link #range(TemporalField) range} and |
| 261 | * {@link #get(TemporalField) get} methods will throw an exception. |
| 262 | * <p> |
| 263 | * If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then |
| 264 | * this method returns true. |
| 265 | * All other {@code ChronoField} instances will return false. |
| 266 | * <p> |
| 267 | * If the field is not a {@code ChronoField}, then the result of this method |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 268 | * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)} |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 269 | * passing {@code this} as the argument. |
| 270 | * Whether the field is supported is determined by the field. |
| 271 | * |
| 272 | * @param field the field to check, null returns false |
| 273 | * @return true if the field is supported on this month-of-year, false if not |
| 274 | */ |
| 275 | @Override |
| 276 | public boolean isSupported(TemporalField field) { |
| 277 | if (field instanceof ChronoField) { |
| 278 | return field == MONTH_OF_YEAR; |
| 279 | } |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 280 | return field != null && field.isSupportedBy(this); |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 281 | } |
| 282 | |
| 283 | /** |
| 284 | * Gets the range of valid values for the specified field. |
| 285 | * <p> |
| 286 | * The range object expresses the minimum and maximum valid values for a field. |
| 287 | * This month is used to enhance the accuracy of the returned range. |
| 288 | * If it is not possible to return the range, because the field is not supported |
| 289 | * or for some other reason, an exception is thrown. |
| 290 | * <p> |
| 291 | * If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the |
| 292 | * range of the month-of-year, from 1 to 12, will be returned. |
| 293 | * All other {@code ChronoField} instances will throw a {@code DateTimeException}. |
| 294 | * <p> |
| 295 | * If the field is not a {@code ChronoField}, then the result of this method |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 296 | * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)} |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 297 | * passing {@code this} as the argument. |
| 298 | * Whether the range can be obtained is determined by the field. |
| 299 | * |
| 300 | * @param field the field to query the range for, not null |
| 301 | * @return the range of valid values for the field, not null |
| 302 | * @throws DateTimeException if the range for the field cannot be obtained |
| 303 | */ |
| 304 | @Override |
| 305 | public ValueRange range(TemporalField field) { |
| 306 | if (field == MONTH_OF_YEAR) { |
| 307 | return field.range(); |
| 308 | } |
| 309 | return TemporalAccessor.super.range(field); |
| 310 | } |
| 311 | |
| 312 | /** |
| 313 | * Gets the value of the specified field from this month-of-year as an {@code int}. |
| 314 | * <p> |
| 315 | * This queries this month for the value for the specified field. |
| 316 | * The returned value will always be within the valid range of values for the field. |
| 317 | * If it is not possible to return the value, because the field is not supported |
| 318 | * or for some other reason, an exception is thrown. |
| 319 | * <p> |
| 320 | * If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the |
| 321 | * value of the month-of-year, from 1 to 12, will be returned. |
| 322 | * All other {@code ChronoField} instances will throw a {@code DateTimeException}. |
| 323 | * <p> |
| 324 | * If the field is not a {@code ChronoField}, then the result of this method |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 325 | * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)} |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 326 | * passing {@code this} as the argument. Whether the value can be obtained, |
| 327 | * and what the value represents, is determined by the field. |
| 328 | * |
| 329 | * @param field the field to get, not null |
| 330 | * @return the value for the field, within the valid range of values |
| 331 | * @throws DateTimeException if a value for the field cannot be obtained |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 332 | * @throws ArithmeticException if numeric overflow occurs |
| 333 | */ |
| 334 | @Override |
| 335 | public int get(TemporalField field) { |
| 336 | if (field == MONTH_OF_YEAR) { |
| 337 | return getValue(); |
| 338 | } |
| 339 | return TemporalAccessor.super.get(field); |
| 340 | } |
| 341 | |
| 342 | /** |
| 343 | * Gets the value of the specified field from this month-of-year as a {@code long}. |
| 344 | * <p> |
| 345 | * This queries this month for the value for the specified field. |
| 346 | * If it is not possible to return the value, because the field is not supported |
| 347 | * or for some other reason, an exception is thrown. |
| 348 | * <p> |
| 349 | * If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the |
| 350 | * value of the month-of-year, from 1 to 12, will be returned. |
| 351 | * All other {@code ChronoField} instances will throw a {@code DateTimeException}. |
| 352 | * <p> |
| 353 | * If the field is not a {@code ChronoField}, then the result of this method |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 354 | * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)} |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 355 | * passing {@code this} as the argument. Whether the value can be obtained, |
| 356 | * and what the value represents, is determined by the field. |
| 357 | * |
| 358 | * @param field the field to get, not null |
| 359 | * @return the value for the field |
| 360 | * @throws DateTimeException if a value for the field cannot be obtained |
| 361 | * @throws ArithmeticException if numeric overflow occurs |
| 362 | */ |
| 363 | @Override |
| 364 | public long getLong(TemporalField field) { |
| 365 | if (field == MONTH_OF_YEAR) { |
| 366 | return getValue(); |
| 367 | } else if (field instanceof ChronoField) { |
| 368 | throw new DateTimeException("Unsupported field: " + field.getName()); |
| 369 | } |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 370 | return field.getFrom(this); |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 371 | } |
| 372 | |
| 373 | //----------------------------------------------------------------------- |
| 374 | /** |
| 375 | * Returns the month-of-year that is the specified number of quarters after this one. |
| 376 | * <p> |
| 377 | * The calculation rolls around the end of the year from December to January. |
| 378 | * The specified period may be negative. |
| 379 | * <p> |
| 380 | * This instance is immutable and unaffected by this method call. |
| 381 | * |
| 382 | * @param months the months to add, positive or negative |
| 383 | * @return the resulting month, not null |
| 384 | */ |
| 385 | public Month plus(long months) { |
| 386 | int amount = (int) (months % 12); |
| 387 | return ENUMS[(ordinal() + (amount + 12)) % 12]; |
| 388 | } |
| 389 | |
| 390 | /** |
| 391 | * Returns the month-of-year that is the specified number of months before this one. |
| 392 | * <p> |
| 393 | * The calculation rolls around the start of the year from January to December. |
| 394 | * The specified period may be negative. |
| 395 | * <p> |
| 396 | * This instance is immutable and unaffected by this method call. |
| 397 | * |
| 398 | * @param months the months to subtract, positive or negative |
| 399 | * @return the resulting month, not null |
| 400 | */ |
| 401 | public Month minus(long months) { |
| 402 | return plus(-(months % 12)); |
| 403 | } |
| 404 | |
| 405 | //----------------------------------------------------------------------- |
| 406 | /** |
| 407 | * Gets the length of this month in days. |
| 408 | * <p> |
| 409 | * This takes a flag to determine whether to return the length for a leap year or not. |
| 410 | * <p> |
| 411 | * February has 28 days in a standard year and 29 days in a leap year. |
| 412 | * April, June, September and November have 30 days. |
| 413 | * All other months have 31 days. |
| 414 | * |
| 415 | * @param leapYear true if the length is required for a leap year |
| 416 | * @return the length of this month in days, from 28 to 31 |
| 417 | */ |
| 418 | public int length(boolean leapYear) { |
| 419 | switch (this) { |
| 420 | case FEBRUARY: |
| 421 | return (leapYear ? 29 : 28); |
| 422 | case APRIL: |
| 423 | case JUNE: |
| 424 | case SEPTEMBER: |
| 425 | case NOVEMBER: |
| 426 | return 30; |
| 427 | default: |
| 428 | return 31; |
| 429 | } |
| 430 | } |
| 431 | |
| 432 | /** |
| 433 | * Gets the minimum length of this month in days. |
| 434 | * <p> |
| 435 | * February has a minimum length of 28 days. |
| 436 | * April, June, September and November have 30 days. |
| 437 | * All other months have 31 days. |
| 438 | * |
| 439 | * @return the minimum length of this month in days, from 28 to 31 |
| 440 | */ |
| 441 | public int minLength() { |
| 442 | switch (this) { |
| 443 | case FEBRUARY: |
| 444 | return 28; |
| 445 | case APRIL: |
| 446 | case JUNE: |
| 447 | case SEPTEMBER: |
| 448 | case NOVEMBER: |
| 449 | return 30; |
| 450 | default: |
| 451 | return 31; |
| 452 | } |
| 453 | } |
| 454 | |
| 455 | /** |
| 456 | * Gets the maximum length of this month in days. |
| 457 | * <p> |
| 458 | * February has a maximum length of 29 days. |
| 459 | * April, June, September and November have 30 days. |
| 460 | * All other months have 31 days. |
| 461 | * |
| 462 | * @return the maximum length of this month in days, from 29 to 31 |
| 463 | */ |
| 464 | public int maxLength() { |
| 465 | switch (this) { |
| 466 | case FEBRUARY: |
| 467 | return 29; |
| 468 | case APRIL: |
| 469 | case JUNE: |
| 470 | case SEPTEMBER: |
| 471 | case NOVEMBER: |
| 472 | return 30; |
| 473 | default: |
| 474 | return 31; |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | //----------------------------------------------------------------------- |
| 479 | /** |
| 480 | * Gets the day-of-year corresponding to the first day of this month. |
| 481 | * <p> |
| 482 | * This returns the day-of-year that this month begins on, using the leap |
| 483 | * year flag to determine the length of February. |
| 484 | * |
| 485 | * @param leapYear true if the length is required for a leap year |
| 486 | * @return the day of year corresponding to the first day of this month, from 1 to 336 |
| 487 | */ |
| 488 | public int firstDayOfYear(boolean leapYear) { |
| 489 | int leap = leapYear ? 1 : 0; |
| 490 | switch (this) { |
| 491 | case JANUARY: |
| 492 | return 1; |
| 493 | case FEBRUARY: |
| 494 | return 32; |
| 495 | case MARCH: |
| 496 | return 60 + leap; |
| 497 | case APRIL: |
| 498 | return 91 + leap; |
| 499 | case MAY: |
| 500 | return 121 + leap; |
| 501 | case JUNE: |
| 502 | return 152 + leap; |
| 503 | case JULY: |
| 504 | return 182 + leap; |
| 505 | case AUGUST: |
| 506 | return 213 + leap; |
| 507 | case SEPTEMBER: |
| 508 | return 244 + leap; |
| 509 | case OCTOBER: |
| 510 | return 274 + leap; |
| 511 | case NOVEMBER: |
| 512 | return 305 + leap; |
| 513 | case DECEMBER: |
| 514 | default: |
| 515 | return 335 + leap; |
| 516 | } |
| 517 | } |
| 518 | |
| 519 | /** |
| 520 | * Gets the month corresponding to the first month of this quarter. |
| 521 | * <p> |
| 522 | * The year can be divided into four quarters. |
| 523 | * This method returns the first month of the quarter for the base month. |
| 524 | * January, February and March return January. |
| 525 | * April, May and June return April. |
| 526 | * July, August and September return July. |
| 527 | * October, November and December return October. |
| 528 | * |
| 529 | * @return the first month of the quarter corresponding to this month, not null |
| 530 | */ |
| 531 | public Month firstMonthOfQuarter() { |
| 532 | return ENUMS[(ordinal() / 3) * 3]; |
| 533 | } |
| 534 | |
| 535 | //----------------------------------------------------------------------- |
| 536 | /** |
| 537 | * Queries this month-of-year using the specified query. |
| 538 | * <p> |
| 539 | * This queries this month-of-year using the specified query strategy object. |
| 540 | * The {@code TemporalQuery} object defines the logic to be used to |
| 541 | * obtain the result. Read the documentation of the query to understand |
| 542 | * what the result of this method will be. |
| 543 | * <p> |
| 544 | * The result of this method is obtained by invoking the |
| 545 | * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the |
| 546 | * specified query passing {@code this} as the argument. |
| 547 | * |
| 548 | * @param <R> the type of the result |
| 549 | * @param query the query to invoke, not null |
| 550 | * @return the query result, null may be returned (defined by the query) |
| 551 | * @throws DateTimeException if unable to query (defined by the query) |
| 552 | * @throws ArithmeticException if numeric overflow occurs (defined by the query) |
| 553 | */ |
| 554 | @SuppressWarnings("unchecked") |
| 555 | @Override |
| 556 | public <R> R query(TemporalQuery<R> query) { |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 557 | if (query == Queries.chronology()) { |
| 558 | return (R) IsoChronology.INSTANCE; |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 559 | } else if (query == Queries.precision()) { |
| 560 | return (R) MONTHS; |
| 561 | } |
| 562 | return TemporalAccessor.super.query(query); |
| 563 | } |
| 564 | |
| 565 | /** |
| 566 | * Adjusts the specified temporal object to have this month-of-year. |
| 567 | * <p> |
| 568 | * This returns a temporal object of the same observable type as the input |
| 569 | * with the month-of-year changed to be the same as this. |
| 570 | * <p> |
| 571 | * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)} |
| 572 | * passing {@link ChronoField#MONTH_OF_YEAR} as the field. |
| 573 | * If the specified temporal object does not use the ISO calendar system then |
| 574 | * a {@code DateTimeException} is thrown. |
| 575 | * <p> |
| 576 | * In most cases, it is clearer to reverse the calling pattern by using |
| 577 | * {@link Temporal#with(TemporalAdjuster)}: |
| 578 | * <pre> |
| 579 | * // these two lines are equivalent, but the second approach is recommended |
| 580 | * temporal = thisMonth.adjustInto(temporal); |
| 581 | * temporal = temporal.with(thisMonth); |
| 582 | * </pre> |
| 583 | * <p> |
| 584 | * For example, given a date in May, the following are output: |
| 585 | * <pre> |
| 586 | * dateInMay.with(JANUARY); // four months earlier |
| 587 | * dateInMay.with(APRIL); // one months earlier |
| 588 | * dateInMay.with(MAY); // same date |
| 589 | * dateInMay.with(JUNE); // one month later |
| 590 | * dateInMay.with(DECEMBER); // seven months later |
| 591 | * </pre> |
| 592 | * <p> |
| 593 | * This instance is immutable and unaffected by this method call. |
| 594 | * |
| 595 | * @param temporal the target object to be adjusted, not null |
| 596 | * @return the adjusted object, not null |
| 597 | * @throws DateTimeException if unable to make the adjustment |
| 598 | * @throws ArithmeticException if numeric overflow occurs |
| 599 | */ |
| 600 | @Override |
| 601 | public Temporal adjustInto(Temporal temporal) { |
Stephen Colebourne | 73c043f | 2013-02-12 09:25:43 -0800 | [diff] [blame^] | 602 | if (Chronology.from(temporal).equals(IsoChronology.INSTANCE) == false) { |
Stephen Colebourne | df4d235 | 2013-01-22 20:59:21 -0800 | [diff] [blame] | 603 | throw new DateTimeException("Adjustment only supported on ISO date-time"); |
| 604 | } |
| 605 | return temporal.with(MONTH_OF_YEAR, getValue()); |
| 606 | } |
| 607 | |
| 608 | } |