| 1 | /* |
| 2 | * Copyright 2001-2006 Stephen Colebourne |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.joda.time.format; |
| 17 | |
| 18 | import java.util.Arrays; |
| 19 | import java.util.Locale; |
| 20 | |
| 21 | import org.joda.time.Chronology; |
| 22 | import org.joda.time.DateTimeField; |
| 23 | import org.joda.time.DateTimeFieldType; |
| 24 | import org.joda.time.DateTimeUtils; |
| 25 | import org.joda.time.DateTimeZone; |
| 26 | import org.joda.time.DurationField; |
| 27 | import org.joda.time.IllegalFieldValueException; |
| 28 | |
| 29 | /** |
| 30 | * DateTimeParserBucket is an advanced class, intended mainly for parser |
| 31 | * implementations. It can also be used during normal parsing operations to |
| 32 | * capture more information about the parse. |
| 33 | * <p> |
| 34 | * This class allows fields to be saved in any order, but be physically set in |
| 35 | * a consistent order. This is useful for parsing against formats that allow |
| 36 | * field values to contradict each other. |
| 37 | * <p> |
| 38 | * Field values are applied in an order where the "larger" fields are set |
| 39 | * first, making their value less likely to stick. A field is larger than |
| 40 | * another when it's range duration is longer. If both ranges are the same, |
| 41 | * then the larger field has the longer duration. If it cannot be determined |
| 42 | * which field is larger, then the fields are set in the order they were saved. |
| 43 | * <p> |
| 44 | * For example, these fields were saved in this order: dayOfWeek, monthOfYear, |
| 45 | * dayOfMonth, dayOfYear. When computeMillis is called, the fields are set in |
| 46 | * this order: monthOfYear, dayOfYear, dayOfMonth, dayOfWeek. |
| 47 | * <p> |
| 48 | * DateTimeParserBucket is mutable and not thread-safe. |
| 49 | * |
| 50 | * @author Brian S O'Neill |
| 51 | * @author Fredrik Borgh |
| 52 | * @since 1.0 |
| 53 | */ |
| 54 | public class DateTimeParserBucket { |
| 55 | |
| 56 | /** The chronology to use for parsing. */ |
| 57 | private final Chronology iChrono; |
| 58 | private final long iMillis; |
| 59 | |
| 60 | // TimeZone to switch to in computeMillis. If null, use offset. |
| 61 | private DateTimeZone iZone; |
| 62 | private int iOffset; |
| 63 | /** The locale to use for parsing. */ |
| 64 | private Locale iLocale; |
| 65 | /** Used for parsing two-digit years. */ |
| 66 | private Integer iPivotYear; |
| 67 | |
| 68 | private SavedField[] iSavedFields = new SavedField[8]; |
| 69 | private int iSavedFieldsCount; |
| 70 | private boolean iSavedFieldsShared; |
| 71 | |
| 72 | private Object iSavedState; |
| 73 | |
| 74 | /** |
| 75 | * Constucts a bucket. |
| 76 | * |
| 77 | * @param instantLocal the initial millis from 1970-01-01T00:00:00, local time |
| 78 | * @param chrono the chronology to use |
| 79 | * @param locale the locale to use |
| 80 | */ |
| 81 | public DateTimeParserBucket(long instantLocal, Chronology chrono, Locale locale) { |
| 82 | this(instantLocal, chrono, locale, null); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Constucts a bucket, with the option of specifying the pivot year for |
| 87 | * two-digit year parsing. |
| 88 | * |
| 89 | * @param instantLocal the initial millis from 1970-01-01T00:00:00, local time |
| 90 | * @param chrono the chronology to use |
| 91 | * @param locale the locale to use |
| 92 | * @param pivotYear the pivot year to use when parsing two-digit years |
| 93 | * @since 1.1 |
| 94 | */ |
| 95 | public DateTimeParserBucket(long instantLocal, Chronology chrono, Locale locale, Integer pivotYear) { |
| 96 | super(); |
| 97 | chrono = DateTimeUtils.getChronology(chrono); |
| 98 | iMillis = instantLocal; |
| 99 | iChrono = chrono.withUTC(); |
| 100 | iLocale = (locale == null ? Locale.getDefault() : locale); |
| 101 | setZone(chrono.getZone()); |
| 102 | iPivotYear = pivotYear; |
| 103 | } |
| 104 | |
| 105 | //----------------------------------------------------------------------- |
| 106 | /** |
| 107 | * Gets the chronology of the bucket, which will be a local (UTC) chronology. |
| 108 | */ |
| 109 | public Chronology getChronology() { |
| 110 | return iChrono; |
| 111 | } |
| 112 | |
| 113 | //----------------------------------------------------------------------- |
| 114 | /** |
| 115 | * Returns the locale to be used during parsing. |
| 116 | * |
| 117 | * @return the locale to use |
| 118 | */ |
| 119 | public Locale getLocale() { |
| 120 | return iLocale; |
| 121 | } |
| 122 | |
| 123 | //----------------------------------------------------------------------- |
| 124 | /** |
| 125 | * Returns the time zone used by computeMillis, or null if an offset is |
| 126 | * used instead. |
| 127 | */ |
| 128 | public DateTimeZone getZone() { |
| 129 | return iZone; |
| 130 | } |
| 131 | |
| 132 | /** |
| 133 | * Set a time zone to be used when computeMillis is called, which |
| 134 | * overrides any set time zone offset. |
| 135 | * |
| 136 | * @param zone the date time zone to operate in, or null if UTC |
| 137 | */ |
| 138 | public void setZone(DateTimeZone zone) { |
| 139 | iSavedState = null; |
| 140 | iZone = zone == DateTimeZone.UTC ? null : zone; |
| 141 | iOffset = 0; |
| 142 | } |
| 143 | |
| 144 | //----------------------------------------------------------------------- |
| 145 | /** |
| 146 | * Returns the time zone offset in milliseconds used by computeMillis, |
| 147 | * unless getZone doesn't return null. |
| 148 | */ |
| 149 | public int getOffset() { |
| 150 | return iOffset; |
| 151 | } |
| 152 | |
| 153 | /** |
| 154 | * Set a time zone offset to be used when computeMillis is called, which |
| 155 | * overrides the time zone. |
| 156 | */ |
| 157 | public void setOffset(int offset) { |
| 158 | iSavedState = null; |
| 159 | iOffset = offset; |
| 160 | iZone = null; |
| 161 | } |
| 162 | |
| 163 | //----------------------------------------------------------------------- |
| 164 | /** |
| 165 | * Returns the pivot year used for parsing two-digit years. |
| 166 | * <p> |
| 167 | * If null is returned, this indicates default behaviour |
| 168 | * |
| 169 | * @return Integer value of the pivot year, null if not set |
| 170 | * @since 1.1 |
| 171 | */ |
| 172 | public Integer getPivotYear() { |
| 173 | return iPivotYear; |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Sets the pivot year to use when parsing two digit years. |
| 178 | * <p> |
| 179 | * If the value is set to null, this will indicate that default |
| 180 | * behaviour should be used. |
| 181 | * |
| 182 | * @param pivotYear the pivot year to use |
| 183 | * @since 1.1 |
| 184 | */ |
| 185 | public void setPivotYear(Integer pivotYear) { |
| 186 | iPivotYear = pivotYear; |
| 187 | } |
| 188 | |
| 189 | //----------------------------------------------------------------------- |
| 190 | /** |
| 191 | * Saves a datetime field value. |
| 192 | * |
| 193 | * @param field the field, whose chronology must match that of this bucket |
| 194 | * @param value the value |
| 195 | */ |
| 196 | public void saveField(DateTimeField field, int value) { |
| 197 | saveField(new SavedField(field, value)); |
| 198 | } |
| 199 | |
| 200 | /** |
| 201 | * Saves a datetime field value. |
| 202 | * |
| 203 | * @param fieldType the field type |
| 204 | * @param value the value |
| 205 | */ |
| 206 | public void saveField(DateTimeFieldType fieldType, int value) { |
| 207 | saveField(new SavedField(fieldType.getField(iChrono), value)); |
| 208 | } |
| 209 | |
| 210 | /** |
| 211 | * Saves a datetime field text value. |
| 212 | * |
| 213 | * @param fieldType the field type |
| 214 | * @param text the text value |
| 215 | * @param locale the locale to use |
| 216 | */ |
| 217 | public void saveField(DateTimeFieldType fieldType, String text, Locale locale) { |
| 218 | saveField(new SavedField(fieldType.getField(iChrono), text, locale)); |
| 219 | } |
| 220 | |
| 221 | private void saveField(SavedField field) { |
| 222 | SavedField[] savedFields = iSavedFields; |
| 223 | int savedFieldsCount = iSavedFieldsCount; |
| 224 | |
| 225 | if (savedFieldsCount == savedFields.length || iSavedFieldsShared) { |
| 226 | // Expand capacity or merely copy if saved fields are shared. |
| 227 | SavedField[] newArray = new SavedField |
| 228 | [savedFieldsCount == savedFields.length ? savedFieldsCount * 2 : savedFields.length]; |
| 229 | System.arraycopy(savedFields, 0, newArray, 0, savedFieldsCount); |
| 230 | iSavedFields = savedFields = newArray; |
| 231 | iSavedFieldsShared = false; |
| 232 | } |
| 233 | |
| 234 | iSavedState = null; |
| 235 | savedFields[savedFieldsCount] = field; |
| 236 | iSavedFieldsCount = savedFieldsCount + 1; |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * Saves the state of this bucket, returning it in an opaque object. Call |
| 241 | * restoreState to undo any changes that were made since the state was |
| 242 | * saved. Calls to saveState may be nested. |
| 243 | * |
| 244 | * @return opaque saved state, which may be passed to restoreState |
| 245 | */ |
| 246 | public Object saveState() { |
| 247 | if (iSavedState == null) { |
| 248 | iSavedState = new SavedState(); |
| 249 | } |
| 250 | return iSavedState; |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * Restores the state of this bucket from a previously saved state. The |
| 255 | * state object passed into this method is not consumed, and it can be used |
| 256 | * later to restore to that state again. |
| 257 | * |
| 258 | * @param savedState opaque saved state, returned from saveState |
| 259 | * @return true state object is valid and state restored |
| 260 | */ |
| 261 | public boolean restoreState(Object savedState) { |
| 262 | if (savedState instanceof SavedState) { |
| 263 | if (((SavedState) savedState).restoreState(this)) { |
| 264 | iSavedState = savedState; |
| 265 | return true; |
| 266 | } |
| 267 | } |
| 268 | return false; |
| 269 | } |
| 270 | |
| 271 | /** |
| 272 | * Computes the parsed datetime by setting the saved fields. |
| 273 | * This method is idempotent, but it is not thread-safe. |
| 274 | * |
| 275 | * @return milliseconds since 1970-01-01T00:00:00Z |
| 276 | * @throws IllegalArgumentException if any field is out of range |
| 277 | */ |
| 278 | public long computeMillis() { |
| 279 | return computeMillis(false, null); |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * Computes the parsed datetime by setting the saved fields. |
| 284 | * This method is idempotent, but it is not thread-safe. |
| 285 | * |
| 286 | * @param resetFields false by default, but when true, unsaved field values are cleared |
| 287 | * @return milliseconds since 1970-01-01T00:00:00Z |
| 288 | * @throws IllegalArgumentException if any field is out of range |
| 289 | */ |
| 290 | public long computeMillis(boolean resetFields) { |
| 291 | return computeMillis(resetFields, null); |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * Computes the parsed datetime by setting the saved fields. |
| 296 | * This method is idempotent, but it is not thread-safe. |
| 297 | * |
| 298 | * @param resetFields false by default, but when true, unsaved field values are cleared |
| 299 | * @param text optional text being parsed, to be included in any error message |
| 300 | * @return milliseconds since 1970-01-01T00:00:00Z |
| 301 | * @throws IllegalArgumentException if any field is out of range |
| 302 | * @since 1.3 |
| 303 | */ |
| 304 | public long computeMillis(boolean resetFields, String text) { |
| 305 | SavedField[] savedFields = iSavedFields; |
| 306 | int count = iSavedFieldsCount; |
| 307 | if (iSavedFieldsShared) { |
| 308 | iSavedFields = savedFields = (SavedField[])iSavedFields.clone(); |
| 309 | iSavedFieldsShared = false; |
| 310 | } |
| 311 | sort(savedFields, count); |
| 312 | |
| 313 | long millis = iMillis; |
| 314 | try { |
| 315 | for (int i=0; i<count; i++) { |
| 316 | millis = savedFields[i].set(millis, resetFields); |
| 317 | } |
| 318 | } catch (IllegalFieldValueException e) { |
| 319 | if (text != null) { |
| 320 | e.prependMessage("Cannot parse \"" + text + '"'); |
| 321 | } |
| 322 | throw e; |
| 323 | } |
| 324 | |
| 325 | if (iZone == null) { |
| 326 | millis -= iOffset; |
| 327 | } else { |
| 328 | int offset = iZone.getOffsetFromLocal(millis); |
| 329 | millis -= offset; |
| 330 | if (offset != iZone.getOffset(millis)) { |
| 331 | String message = |
| 332 | "Illegal instant due to time zone offset transition (" + iZone + ')'; |
| 333 | if (text != null) { |
| 334 | message = "Cannot parse \"" + text + "\": " + message; |
| 335 | } |
| 336 | throw new IllegalArgumentException(message); |
| 337 | } |
| 338 | } |
| 339 | |
| 340 | return millis; |
| 341 | } |
| 342 | |
| 343 | /** |
| 344 | * Sorts elements [0,high). Calling java.util.Arrays isn't always the right |
| 345 | * choice since it always creates an internal copy of the array, even if it |
| 346 | * doesn't need to. If the array slice is small enough, an insertion sort |
| 347 | * is chosen instead, but it doesn't need a copy! |
| 348 | * <p> |
| 349 | * This method has a modified version of that insertion sort, except it |
| 350 | * doesn't create an unnecessary array copy. If high is over 10, then |
| 351 | * java.util.Arrays is called, which will perform a merge sort, which is |
| 352 | * faster than insertion sort on large lists. |
| 353 | * <p> |
| 354 | * The end result is much greater performace when computeMillis is called. |
| 355 | * Since the amount of saved fields is small, the insertion sort is a |
| 356 | * better choice. Additional performance is gained since there is no extra |
| 357 | * array allocation and copying. Also, the insertion sort here does not |
| 358 | * perform any casting operations. The version in java.util.Arrays performs |
| 359 | * casts within the insertion sort loop. |
| 360 | */ |
| 361 | private static void sort(Comparable[] array, int high) { |
| 362 | if (high > 10) { |
| 363 | Arrays.sort(array, 0, high); |
| 364 | } else { |
| 365 | for (int i=0; i<high; i++) { |
| 366 | for (int j=i; j>0 && (array[j-1]).compareTo(array[j])>0; j--) { |
| 367 | Comparable t = array[j]; |
| 368 | array[j] = array[j-1]; |
| 369 | array[j-1] = t; |
| 370 | } |
| 371 | } |
| 372 | } |
| 373 | } |
| 374 | |
| 375 | class SavedState { |
| 376 | final DateTimeZone iZone; |
| 377 | final int iOffset; |
| 378 | final SavedField[] iSavedFields; |
| 379 | final int iSavedFieldsCount; |
| 380 | |
| 381 | SavedState() { |
| 382 | this.iZone = DateTimeParserBucket.this.iZone; |
| 383 | this.iOffset = DateTimeParserBucket.this.iOffset; |
| 384 | this.iSavedFields = DateTimeParserBucket.this.iSavedFields; |
| 385 | this.iSavedFieldsCount = DateTimeParserBucket.this.iSavedFieldsCount; |
| 386 | } |
| 387 | |
| 388 | boolean restoreState(DateTimeParserBucket enclosing) { |
| 389 | if (enclosing != DateTimeParserBucket.this) { |
| 390 | return false; |
| 391 | } |
| 392 | enclosing.iZone = this.iZone; |
| 393 | enclosing.iOffset = this.iOffset; |
| 394 | enclosing.iSavedFields = this.iSavedFields; |
| 395 | if (this.iSavedFieldsCount < enclosing.iSavedFieldsCount) { |
| 396 | // Since count is being restored to a lower count, the |
| 397 | // potential exists for new saved fields to destroy data being |
| 398 | // shared by another state. Set this flag such that the array |
| 399 | // of saved fields is cloned prior to modification. |
| 400 | enclosing.iSavedFieldsShared = true; |
| 401 | } |
| 402 | enclosing.iSavedFieldsCount = this.iSavedFieldsCount; |
| 403 | return true; |
| 404 | } |
| 405 | } |
| 406 | |
| 407 | static class SavedField implements Comparable { |
| 408 | final DateTimeField iField; |
| 409 | final int iValue; |
| 410 | final String iText; |
| 411 | final Locale iLocale; |
| 412 | |
| 413 | SavedField(DateTimeField field, int value) { |
| 414 | iField = field; |
| 415 | iValue = value; |
| 416 | iText = null; |
| 417 | iLocale = null; |
| 418 | } |
| 419 | |
| 420 | SavedField(DateTimeField field, String text, Locale locale) { |
| 421 | iField = field; |
| 422 | iValue = 0; |
| 423 | iText = text; |
| 424 | iLocale = locale; |
| 425 | } |
| 426 | |
| 427 | long set(long millis, boolean reset) { |
| 428 | if (iText == null) { |
| 429 | millis = iField.set(millis, iValue); |
| 430 | } else { |
| 431 | millis = iField.set(millis, iText, iLocale); |
| 432 | } |
| 433 | if (reset) { |
| 434 | millis = iField.roundFloor(millis); |
| 435 | } |
| 436 | return millis; |
| 437 | } |
| 438 | |
| 439 | /** |
| 440 | * The field with the longer range duration is ordered first, where |
| 441 | * null is considered infinite. If the ranges match, then the field |
| 442 | * with the longer duration is ordered first. |
| 443 | */ |
| 444 | public int compareTo(Object obj) { |
| 445 | DateTimeField other = ((SavedField)obj).iField; |
| 446 | int result = compareReverse |
| 447 | (iField.getRangeDurationField(), other.getRangeDurationField()); |
| 448 | if (result != 0) { |
| 449 | return result; |
| 450 | } |
| 451 | return compareReverse |
| 452 | (iField.getDurationField(), other.getDurationField()); |
| 453 | } |
| 454 | |
| 455 | private int compareReverse(DurationField a, DurationField b) { |
| 456 | if (a == null || !a.isSupported()) { |
| 457 | if (b == null || !b.isSupported()) { |
| 458 | return 0; |
| 459 | } |
| 460 | return -1; |
| 461 | } |
| 462 | if (b == null || !b.isSupported()) { |
| 463 | return 1; |
| 464 | } |
| 465 | return -a.compareTo(b); |
| 466 | } |
| 467 | } |
| 468 | } |