J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1996-2005 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | /* |
| 27 | * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved |
| 28 | * (C) Copyright IBM Corp. 1996 - All Rights Reserved |
| 29 | * |
| 30 | * The original version of this source code and documentation is copyrighted |
| 31 | * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These |
| 32 | * materials are provided under terms of a License Agreement between Taligent |
| 33 | * and Sun. This technology is protected by multiple US and International |
| 34 | * patents. This notice and attribution to Taligent may not be removed. |
| 35 | * Taligent is a registered trademark of Taligent, Inc. |
| 36 | * |
| 37 | */ |
| 38 | |
| 39 | package java.util; |
| 40 | |
| 41 | import java.io.Serializable; |
| 42 | import java.lang.ref.SoftReference; |
| 43 | import java.security.AccessController; |
| 44 | import java.security.PrivilegedAction; |
| 45 | import java.util.concurrent.ConcurrentHashMap; |
| 46 | import sun.security.action.GetPropertyAction; |
| 47 | import sun.util.TimeZoneNameUtility; |
| 48 | import sun.util.calendar.ZoneInfo; |
| 49 | import sun.util.calendar.ZoneInfoFile; |
| 50 | |
| 51 | /** |
| 52 | * <code>TimeZone</code> represents a time zone offset, and also figures out daylight |
| 53 | * savings. |
| 54 | * |
| 55 | * <p> |
| 56 | * Typically, you get a <code>TimeZone</code> using <code>getDefault</code> |
| 57 | * which creates a <code>TimeZone</code> based on the time zone where the program |
| 58 | * is running. For example, for a program running in Japan, <code>getDefault</code> |
| 59 | * creates a <code>TimeZone</code> object based on Japanese Standard Time. |
| 60 | * |
| 61 | * <p> |
| 62 | * You can also get a <code>TimeZone</code> using <code>getTimeZone</code> |
| 63 | * along with a time zone ID. For instance, the time zone ID for the |
| 64 | * U.S. Pacific Time zone is "America/Los_Angeles". So, you can get a |
| 65 | * U.S. Pacific Time <code>TimeZone</code> object with: |
| 66 | * <blockquote><pre> |
| 67 | * TimeZone tz = TimeZone.getTimeZone("America/Los_Angeles"); |
| 68 | * </pre></blockquote> |
| 69 | * You can use the <code>getAvailableIDs</code> method to iterate through |
| 70 | * all the supported time zone IDs. You can then choose a |
| 71 | * supported ID to get a <code>TimeZone</code>. |
| 72 | * If the time zone you want is not represented by one of the |
| 73 | * supported IDs, then a custom time zone ID can be specified to |
| 74 | * produce a TimeZone. The syntax of a custom time zone ID is: |
| 75 | * |
| 76 | * <blockquote><pre> |
| 77 | * <a name="CustomID"><i>CustomID:</i></a> |
| 78 | * <code>GMT</code> <i>Sign</i> <i>Hours</i> <code>:</code> <i>Minutes</i> |
| 79 | * <code>GMT</code> <i>Sign</i> <i>Hours</i> <i>Minutes</i> |
| 80 | * <code>GMT</code> <i>Sign</i> <i>Hours</i> |
| 81 | * <i>Sign:</i> one of |
| 82 | * <code>+ -</code> |
| 83 | * <i>Hours:</i> |
| 84 | * <i>Digit</i> |
| 85 | * <i>Digit</i> <i>Digit</i> |
| 86 | * <i>Minutes:</i> |
| 87 | * <i>Digit</i> <i>Digit</i> |
| 88 | * <i>Digit:</i> one of |
| 89 | * <code>0 1 2 3 4 5 6 7 8 9</code> |
| 90 | * </pre></blockquote> |
| 91 | * |
| 92 | * <i>Hours</i> must be between 0 to 23 and <i>Minutes</i> must be |
| 93 | * between 00 to 59. For example, "GMT+10" and "GMT+0010" mean ten |
| 94 | * hours and ten minutes ahead of GMT, respectively. |
| 95 | * <p> |
| 96 | * The format is locale independent and digits must be taken from the |
| 97 | * Basic Latin block of the Unicode standard. No daylight saving time |
| 98 | * transition schedule can be specified with a custom time zone ID. If |
| 99 | * the specified string doesn't match the syntax, <code>"GMT"</code> |
| 100 | * is used. |
| 101 | * <p> |
| 102 | * When creating a <code>TimeZone</code>, the specified custom time |
| 103 | * zone ID is normalized in the following syntax: |
| 104 | * <blockquote><pre> |
| 105 | * <a name="NormalizedCustomID"><i>NormalizedCustomID:</i></a> |
| 106 | * <code>GMT</code> <i>Sign</i> <i>TwoDigitHours</i> <code>:</code> <i>Minutes</i> |
| 107 | * <i>Sign:</i> one of |
| 108 | * <code>+ -</code> |
| 109 | * <i>TwoDigitHours:</i> |
| 110 | * <i>Digit</i> <i>Digit</i> |
| 111 | * <i>Minutes:</i> |
| 112 | * <i>Digit</i> <i>Digit</i> |
| 113 | * <i>Digit:</i> one of |
| 114 | * <code>0 1 2 3 4 5 6 7 8 9</code> |
| 115 | * </pre></blockquote> |
| 116 | * For example, TimeZone.getTimeZone("GMT-8").getID() returns "GMT-08:00". |
| 117 | * |
| 118 | * <h4>Three-letter time zone IDs</h4> |
| 119 | * |
| 120 | * For compatibility with JDK 1.1.x, some other three-letter time zone IDs |
| 121 | * (such as "PST", "CTT", "AST") are also supported. However, <strong>their |
| 122 | * use is deprecated</strong> because the same abbreviation is often used |
| 123 | * for multiple time zones (for example, "CST" could be U.S. "Central Standard |
| 124 | * Time" and "China Standard Time"), and the Java platform can then only |
| 125 | * recognize one of them. |
| 126 | * |
| 127 | * |
| 128 | * @see Calendar |
| 129 | * @see GregorianCalendar |
| 130 | * @see SimpleTimeZone |
| 131 | * @author Mark Davis, David Goldsmith, Chen-Lieh Huang, Alan Liu |
| 132 | * @since JDK1.1 |
| 133 | */ |
| 134 | abstract public class TimeZone implements Serializable, Cloneable { |
| 135 | /** |
| 136 | * Sole constructor. (For invocation by subclass constructors, typically |
| 137 | * implicit.) |
| 138 | */ |
| 139 | public TimeZone() { |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | * A style specifier for <code>getDisplayName()</code> indicating |
| 144 | * a short name, such as "PST." |
| 145 | * @see #LONG |
| 146 | * @since 1.2 |
| 147 | */ |
| 148 | public static final int SHORT = 0; |
| 149 | |
| 150 | /** |
| 151 | * A style specifier for <code>getDisplayName()</code> indicating |
| 152 | * a long name, such as "Pacific Standard Time." |
| 153 | * @see #SHORT |
| 154 | * @since 1.2 |
| 155 | */ |
| 156 | public static final int LONG = 1; |
| 157 | |
| 158 | // Constants used internally; unit is milliseconds |
| 159 | private static final int ONE_MINUTE = 60*1000; |
| 160 | private static final int ONE_HOUR = 60*ONE_MINUTE; |
| 161 | private static final int ONE_DAY = 24*ONE_HOUR; |
| 162 | |
| 163 | /** |
| 164 | * Cache to hold the SimpleDateFormat objects for a Locale. |
| 165 | */ |
| 166 | private static Hashtable cachedLocaleData = new Hashtable(3); |
| 167 | |
| 168 | // Proclaim serialization compatibility with JDK 1.1 |
| 169 | static final long serialVersionUID = 3581463369166924961L; |
| 170 | |
| 171 | /** |
| 172 | * Gets the time zone offset, for current date, modified in case of |
| 173 | * daylight savings. This is the offset to add to UTC to get local time. |
| 174 | * <p> |
| 175 | * This method returns a historically correct offset if an |
| 176 | * underlying <code>TimeZone</code> implementation subclass |
| 177 | * supports historical Daylight Saving Time schedule and GMT |
| 178 | * offset changes. |
| 179 | * |
| 180 | * @param era the era of the given date. |
| 181 | * @param year the year in the given date. |
| 182 | * @param month the month in the given date. |
| 183 | * Month is 0-based. e.g., 0 for January. |
| 184 | * @param day the day-in-month of the given date. |
| 185 | * @param dayOfWeek the day-of-week of the given date. |
| 186 | * @param milliseconds the milliseconds in day in <em>standard</em> |
| 187 | * local time. |
| 188 | * |
| 189 | * @return the offset in milliseconds to add to GMT to get local time. |
| 190 | * |
| 191 | * @see Calendar#ZONE_OFFSET |
| 192 | * @see Calendar#DST_OFFSET |
| 193 | */ |
| 194 | public abstract int getOffset(int era, int year, int month, int day, |
| 195 | int dayOfWeek, int milliseconds); |
| 196 | |
| 197 | /** |
| 198 | * Returns the offset of this time zone from UTC at the specified |
| 199 | * date. If Daylight Saving Time is in effect at the specified |
| 200 | * date, the offset value is adjusted with the amount of daylight |
| 201 | * saving. |
| 202 | * <p> |
| 203 | * This method returns a historically correct offset value if an |
| 204 | * underlying TimeZone implementation subclass supports historical |
| 205 | * Daylight Saving Time schedule and GMT offset changes. |
| 206 | * |
| 207 | * @param date the date represented in milliseconds since January 1, 1970 00:00:00 GMT |
| 208 | * @return the amount of time in milliseconds to add to UTC to get local time. |
| 209 | * |
| 210 | * @see Calendar#ZONE_OFFSET |
| 211 | * @see Calendar#DST_OFFSET |
| 212 | * @since 1.4 |
| 213 | */ |
| 214 | public int getOffset(long date) { |
| 215 | if (inDaylightTime(new Date(date))) { |
| 216 | return getRawOffset() + getDSTSavings(); |
| 217 | } |
| 218 | return getRawOffset(); |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * Gets the raw GMT offset and the amount of daylight saving of this |
| 223 | * time zone at the given time. |
| 224 | * @param date the milliseconds (since January 1, 1970, |
| 225 | * 00:00:00.000 GMT) at which the time zone offset and daylight |
| 226 | * saving amount are found |
| 227 | * @param offset an array of int where the raw GMT offset |
| 228 | * (offset[0]) and daylight saving amount (offset[1]) are stored, |
| 229 | * or null if those values are not needed. The method assumes that |
| 230 | * the length of the given array is two or larger. |
| 231 | * @return the total amount of the raw GMT offset and daylight |
| 232 | * saving at the specified date. |
| 233 | * |
| 234 | * @see Calendar#ZONE_OFFSET |
| 235 | * @see Calendar#DST_OFFSET |
| 236 | */ |
| 237 | int getOffsets(long date, int[] offsets) { |
| 238 | int rawoffset = getRawOffset(); |
| 239 | int dstoffset = 0; |
| 240 | if (inDaylightTime(new Date(date))) { |
| 241 | dstoffset = getDSTSavings(); |
| 242 | } |
| 243 | if (offsets != null) { |
| 244 | offsets[0] = rawoffset; |
| 245 | offsets[1] = dstoffset; |
| 246 | } |
| 247 | return rawoffset + dstoffset; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * Sets the base time zone offset to GMT. |
| 252 | * This is the offset to add to UTC to get local time. |
| 253 | * <p> |
| 254 | * If an underlying <code>TimeZone</code> implementation subclass |
| 255 | * supports historical GMT offset changes, the specified GMT |
| 256 | * offset is set as the latest GMT offset and the difference from |
| 257 | * the known latest GMT offset value is used to adjust all |
| 258 | * historical GMT offset values. |
| 259 | * |
| 260 | * @param offsetMillis the given base time zone offset to GMT. |
| 261 | */ |
| 262 | abstract public void setRawOffset(int offsetMillis); |
| 263 | |
| 264 | /** |
| 265 | * Returns the amount of time in milliseconds to add to UTC to get |
| 266 | * standard time in this time zone. Because this value is not |
| 267 | * affected by daylight saving time, it is called <I>raw |
| 268 | * offset</I>. |
| 269 | * <p> |
| 270 | * If an underlying <code>TimeZone</code> implementation subclass |
| 271 | * supports historical GMT offset changes, the method returns the |
| 272 | * raw offset value of the current date. In Honolulu, for example, |
| 273 | * its raw offset changed from GMT-10:30 to GMT-10:00 in 1947, and |
| 274 | * this method always returns -36000000 milliseconds (i.e., -10 |
| 275 | * hours). |
| 276 | * |
| 277 | * @return the amount of raw offset time in milliseconds to add to UTC. |
| 278 | * @see Calendar#ZONE_OFFSET |
| 279 | */ |
| 280 | public abstract int getRawOffset(); |
| 281 | |
| 282 | /** |
| 283 | * Gets the ID of this time zone. |
| 284 | * @return the ID of this time zone. |
| 285 | */ |
| 286 | public String getID() |
| 287 | { |
| 288 | return ID; |
| 289 | } |
| 290 | |
| 291 | /** |
| 292 | * Sets the time zone ID. This does not change any other data in |
| 293 | * the time zone object. |
| 294 | * @param ID the new time zone ID. |
| 295 | */ |
| 296 | public void setID(String ID) |
| 297 | { |
| 298 | if (ID == null) { |
| 299 | throw new NullPointerException(); |
| 300 | } |
| 301 | this.ID = ID; |
| 302 | } |
| 303 | |
| 304 | /** |
| 305 | * Returns a name of this time zone suitable for presentation to the user |
| 306 | * in the default locale. |
| 307 | * This method returns the long name, not including daylight savings. |
| 308 | * If the display name is not available for the locale, |
| 309 | * then this method returns a string in the |
| 310 | * <a href="#NormalizedCustomID">normalized custom ID format</a>. |
| 311 | * @return the human-readable name of this time zone in the default locale. |
| 312 | * @since 1.2 |
| 313 | */ |
| 314 | public final String getDisplayName() { |
| 315 | return getDisplayName(false, LONG, Locale.getDefault()); |
| 316 | } |
| 317 | |
| 318 | /** |
| 319 | * Returns a name of this time zone suitable for presentation to the user |
| 320 | * in the specified locale. |
| 321 | * This method returns the long name, not including daylight savings. |
| 322 | * If the display name is not available for the locale, |
| 323 | * then this method returns a string in the |
| 324 | * <a href="#NormalizedCustomID">normalized custom ID format</a>. |
| 325 | * @param locale the locale in which to supply the display name. |
| 326 | * @return the human-readable name of this time zone in the given locale. |
| 327 | * @since 1.2 |
| 328 | */ |
| 329 | public final String getDisplayName(Locale locale) { |
| 330 | return getDisplayName(false, LONG, locale); |
| 331 | } |
| 332 | |
| 333 | /** |
| 334 | * Returns a name of this time zone suitable for presentation to the user |
| 335 | * in the default locale. |
| 336 | * If the display name is not available for the locale, then this |
| 337 | * method returns a string in the |
| 338 | * <a href="#NormalizedCustomID">normalized custom ID format</a>. |
| 339 | * @param daylight if true, return the daylight savings name. |
| 340 | * @param style either <code>LONG</code> or <code>SHORT</code> |
| 341 | * @return the human-readable name of this time zone in the default locale. |
| 342 | * @since 1.2 |
| 343 | */ |
| 344 | public final String getDisplayName(boolean daylight, int style) { |
| 345 | return getDisplayName(daylight, style, Locale.getDefault()); |
| 346 | } |
| 347 | |
| 348 | /** |
| 349 | * Returns a name of this time zone suitable for presentation to the user |
| 350 | * in the specified locale. |
| 351 | * If the display name is not available for the locale, |
| 352 | * then this method returns a string in the |
| 353 | * <a href="#NormalizedCustomID">normalized custom ID format</a>. |
| 354 | * @param daylight if true, return the daylight savings name. |
| 355 | * @param style either <code>LONG</code> or <code>SHORT</code> |
| 356 | * @param locale the locale in which to supply the display name. |
| 357 | * @return the human-readable name of this time zone in the given locale. |
| 358 | * @exception IllegalArgumentException style is invalid. |
| 359 | * @since 1.2 |
| 360 | */ |
| 361 | public String getDisplayName(boolean daylight, int style, Locale locale) { |
| 362 | if (style != SHORT && style != LONG) { |
| 363 | throw new IllegalArgumentException("Illegal style: " + style); |
| 364 | } |
| 365 | |
| 366 | String id = getID(); |
| 367 | String[] names = getDisplayNames(id, locale); |
| 368 | if (names == null) { |
| 369 | if (id.startsWith("GMT")) { |
| 370 | char sign = id.charAt(3); |
| 371 | if (sign == '+' || sign == '-') { |
| 372 | return id; |
| 373 | } |
| 374 | } |
| 375 | int offset = getRawOffset(); |
| 376 | if (daylight) { |
| 377 | offset += getDSTSavings(); |
| 378 | } |
| 379 | return ZoneInfoFile.toCustomID(offset); |
| 380 | } |
| 381 | |
| 382 | int index = daylight ? 3 : 1; |
| 383 | if (style == SHORT) { |
| 384 | index++; |
| 385 | } |
| 386 | return names[index]; |
| 387 | } |
| 388 | |
| 389 | private static class DisplayNames { |
| 390 | // Cache for managing display names per timezone per locale |
| 391 | // The structure is: |
| 392 | // Map(key=id, value=SoftReference(Map(key=locale, value=displaynames))) |
| 393 | private static final Map<String, SoftReference<Map<Locale, String[]>>> CACHE = |
| 394 | new ConcurrentHashMap<String, SoftReference<Map<Locale, String[]>>>(); |
| 395 | } |
| 396 | |
| 397 | private static final String[] getDisplayNames(String id, Locale locale) { |
| 398 | Map<String, SoftReference<Map<Locale, String[]>>> displayNames = DisplayNames.CACHE; |
| 399 | |
| 400 | SoftReference<Map<Locale, String[]>> ref = displayNames.get(id); |
| 401 | if (ref != null) { |
| 402 | Map<Locale, String[]> perLocale = ref.get(); |
| 403 | if (perLocale != null) { |
| 404 | String[] names = perLocale.get(locale); |
| 405 | if (names != null) { |
| 406 | return names; |
| 407 | } |
| 408 | names = TimeZoneNameUtility.retrieveDisplayNames(id, locale); |
| 409 | if (names != null) { |
| 410 | perLocale.put(locale, names); |
| 411 | } |
| 412 | return names; |
| 413 | } |
| 414 | } |
| 415 | |
| 416 | String[] names = TimeZoneNameUtility.retrieveDisplayNames(id, locale); |
| 417 | if (names != null) { |
| 418 | Map<Locale, String[]> perLocale = new ConcurrentHashMap<Locale, String[]>(); |
| 419 | perLocale.put(locale, names); |
| 420 | ref = new SoftReference<Map<Locale, String[]>>(perLocale); |
| 421 | displayNames.put(id, ref); |
| 422 | } |
| 423 | return names; |
| 424 | } |
| 425 | |
| 426 | /** |
| 427 | * Returns the amount of time to be added to local standard time |
| 428 | * to get local wall clock time. |
| 429 | * <p> |
| 430 | * The default implementation always returns 3600000 milliseconds |
| 431 | * (i.e., one hour) if this time zone observes Daylight Saving |
| 432 | * Time. Otherwise, 0 (zero) is returned. |
| 433 | * <p> |
| 434 | * If an underlying TimeZone implementation subclass supports |
| 435 | * historical Daylight Saving Time changes, this method returns |
| 436 | * the known latest daylight saving value. |
| 437 | * |
| 438 | * @return the amount of saving time in milliseconds |
| 439 | * @since 1.4 |
| 440 | */ |
| 441 | public int getDSTSavings() { |
| 442 | if (useDaylightTime()) { |
| 443 | return 3600000; |
| 444 | } |
| 445 | return 0; |
| 446 | } |
| 447 | |
| 448 | /** |
| 449 | * Queries if this time zone uses daylight savings time. |
| 450 | * <p> |
| 451 | * If an underlying <code>TimeZone</code> implementation subclass |
| 452 | * supports historical Daylight Saving Time schedule changes, the |
| 453 | * method refers to the latest Daylight Saving Time schedule |
| 454 | * information. |
| 455 | * |
| 456 | * @return true if this time zone uses daylight savings time, |
| 457 | * false, otherwise. |
| 458 | */ |
| 459 | public abstract boolean useDaylightTime(); |
| 460 | |
| 461 | /** |
| 462 | * Queries if the given date is in daylight savings time in |
| 463 | * this time zone. |
| 464 | * @param date the given Date. |
| 465 | * @return true if the given date is in daylight savings time, |
| 466 | * false, otherwise. |
| 467 | */ |
| 468 | abstract public boolean inDaylightTime(Date date); |
| 469 | |
| 470 | /** |
| 471 | * Gets the <code>TimeZone</code> for the given ID. |
| 472 | * |
| 473 | * @param ID the ID for a <code>TimeZone</code>, either an abbreviation |
| 474 | * such as "PST", a full name such as "America/Los_Angeles", or a custom |
| 475 | * ID such as "GMT-8:00". Note that the support of abbreviations is |
| 476 | * for JDK 1.1.x compatibility only and full names should be used. |
| 477 | * |
| 478 | * @return the specified <code>TimeZone</code>, or the GMT zone if the given ID |
| 479 | * cannot be understood. |
| 480 | */ |
| 481 | public static synchronized TimeZone getTimeZone(String ID) { |
| 482 | return getTimeZone(ID, true); |
| 483 | } |
| 484 | |
| 485 | private static TimeZone getTimeZone(String ID, boolean fallback) { |
| 486 | TimeZone tz = ZoneInfo.getTimeZone(ID); |
| 487 | if (tz == null) { |
| 488 | tz = parseCustomTimeZone(ID); |
| 489 | if (tz == null && fallback) { |
| 490 | tz = new ZoneInfo(GMT_ID, 0); |
| 491 | } |
| 492 | } |
| 493 | return tz; |
| 494 | } |
| 495 | |
| 496 | /** |
| 497 | * Gets the available IDs according to the given time zone offset in milliseconds. |
| 498 | * |
| 499 | * @param rawOffset the given time zone GMT offset in milliseconds. |
| 500 | * @return an array of IDs, where the time zone for that ID has |
| 501 | * the specified GMT offset. For example, "America/Phoenix" and "America/Denver" |
| 502 | * both have GMT-07:00, but differ in daylight savings behavior. |
| 503 | * @see #getRawOffset() |
| 504 | */ |
| 505 | public static synchronized String[] getAvailableIDs(int rawOffset) { |
| 506 | return ZoneInfo.getAvailableIDs(rawOffset); |
| 507 | } |
| 508 | |
| 509 | /** |
| 510 | * Gets all the available IDs supported. |
| 511 | * @return an array of IDs. |
| 512 | */ |
| 513 | public static synchronized String[] getAvailableIDs() { |
| 514 | return ZoneInfo.getAvailableIDs(); |
| 515 | } |
| 516 | |
| 517 | /** |
| 518 | * Gets the platform defined TimeZone ID. |
| 519 | **/ |
| 520 | private static native String getSystemTimeZoneID(String javaHome, |
| 521 | String country); |
| 522 | |
| 523 | /** |
| 524 | * Gets the custom time zone ID based on the GMT offset of the |
| 525 | * platform. (e.g., "GMT+08:00") |
| 526 | */ |
| 527 | private static native String getSystemGMTOffsetID(); |
| 528 | |
| 529 | /** |
| 530 | * Gets the default <code>TimeZone</code> for this host. |
| 531 | * The source of the default <code>TimeZone</code> |
| 532 | * may vary with implementation. |
| 533 | * @return a default <code>TimeZone</code>. |
| 534 | * @see #setDefault |
| 535 | */ |
| 536 | public static TimeZone getDefault() { |
| 537 | return (TimeZone) getDefaultRef().clone(); |
| 538 | } |
| 539 | |
| 540 | /** |
| 541 | * Returns the reference to the default TimeZone object. This |
| 542 | * method doesn't create a clone. |
| 543 | */ |
| 544 | static TimeZone getDefaultRef() { |
| 545 | TimeZone defaultZone = defaultZoneTL.get(); |
| 546 | if (defaultZone == null) { |
| 547 | defaultZone = defaultTimeZone; |
| 548 | if (defaultZone == null) { |
| 549 | // Need to initialize the default time zone. |
| 550 | defaultZone = setDefaultZone(); |
| 551 | assert defaultZone != null; |
| 552 | } |
| 553 | } |
| 554 | // Don't clone here. |
| 555 | return defaultZone; |
| 556 | } |
| 557 | |
| 558 | private static synchronized TimeZone setDefaultZone() { |
| 559 | TimeZone tz = null; |
| 560 | // get the time zone ID from the system properties |
| 561 | String zoneID = AccessController.doPrivileged( |
| 562 | new GetPropertyAction("user.timezone")); |
| 563 | |
| 564 | // if the time zone ID is not set (yet), perform the |
| 565 | // platform to Java time zone ID mapping. |
| 566 | if (zoneID == null || zoneID.equals("")) { |
| 567 | String country = AccessController.doPrivileged( |
| 568 | new GetPropertyAction("user.country")); |
| 569 | String javaHome = AccessController.doPrivileged( |
| 570 | new GetPropertyAction("java.home")); |
| 571 | try { |
| 572 | zoneID = getSystemTimeZoneID(javaHome, country); |
| 573 | if (zoneID == null) { |
| 574 | zoneID = GMT_ID; |
| 575 | } |
| 576 | } catch (NullPointerException e) { |
| 577 | zoneID = GMT_ID; |
| 578 | } |
| 579 | } |
| 580 | |
| 581 | // Get the time zone for zoneID. But not fall back to |
| 582 | // "GMT" here. |
| 583 | tz = getTimeZone(zoneID, false); |
| 584 | |
| 585 | if (tz == null) { |
| 586 | // If the given zone ID is unknown in Java, try to |
| 587 | // get the GMT-offset-based time zone ID, |
| 588 | // a.k.a. custom time zone ID (e.g., "GMT-08:00"). |
| 589 | String gmtOffsetID = getSystemGMTOffsetID(); |
| 590 | if (gmtOffsetID != null) { |
| 591 | zoneID = gmtOffsetID; |
| 592 | } |
| 593 | tz = getTimeZone(zoneID, true); |
| 594 | } |
| 595 | assert tz != null; |
| 596 | |
| 597 | final String id = zoneID; |
| 598 | AccessController.doPrivileged(new PrivilegedAction<Object>() { |
| 599 | public Object run() { |
| 600 | System.setProperty("user.timezone", id); |
| 601 | return null; |
| 602 | } |
| 603 | }); |
| 604 | |
| 605 | defaultTimeZone = tz; |
| 606 | return tz; |
| 607 | } |
| 608 | |
| 609 | private static boolean hasPermission() { |
| 610 | boolean hasPermission = true; |
| 611 | SecurityManager sm = System.getSecurityManager(); |
| 612 | if (sm != null) { |
| 613 | try { |
| 614 | sm.checkPermission(new PropertyPermission |
| 615 | ("user.timezone", "write")); |
| 616 | } catch (SecurityException e) { |
| 617 | hasPermission = false; |
| 618 | } |
| 619 | } |
| 620 | return hasPermission; |
| 621 | } |
| 622 | |
| 623 | /** |
| 624 | * Sets the <code>TimeZone</code> that is |
| 625 | * returned by the <code>getDefault</code> method. If <code>zone</code> |
| 626 | * is null, reset the default to the value it had originally when the |
| 627 | * VM first started. |
| 628 | * @param zone the new default time zone |
| 629 | * @see #getDefault |
| 630 | */ |
| 631 | public static void setDefault(TimeZone zone) |
| 632 | { |
| 633 | if (hasPermission()) { |
| 634 | synchronized (TimeZone.class) { |
| 635 | defaultTimeZone = zone; |
| 636 | defaultZoneTL.set(null); |
| 637 | } |
| 638 | } else { |
| 639 | defaultZoneTL.set(zone); |
| 640 | } |
| 641 | } |
| 642 | |
| 643 | /** |
| 644 | * Returns true if this zone has the same rule and offset as another zone. |
| 645 | * That is, if this zone differs only in ID, if at all. Returns false |
| 646 | * if the other zone is null. |
| 647 | * @param other the <code>TimeZone</code> object to be compared with |
| 648 | * @return true if the other zone is not null and is the same as this one, |
| 649 | * with the possible exception of the ID |
| 650 | * @since 1.2 |
| 651 | */ |
| 652 | public boolean hasSameRules(TimeZone other) { |
| 653 | return other != null && getRawOffset() == other.getRawOffset() && |
| 654 | useDaylightTime() == other.useDaylightTime(); |
| 655 | } |
| 656 | |
| 657 | /** |
| 658 | * Creates a copy of this <code>TimeZone</code>. |
| 659 | * |
| 660 | * @return a clone of this <code>TimeZone</code> |
| 661 | */ |
| 662 | public Object clone() |
| 663 | { |
| 664 | try { |
| 665 | TimeZone other = (TimeZone) super.clone(); |
| 666 | other.ID = ID; |
| 667 | return other; |
| 668 | } catch (CloneNotSupportedException e) { |
| 669 | throw new InternalError(); |
| 670 | } |
| 671 | } |
| 672 | |
| 673 | /** |
| 674 | * The null constant as a TimeZone. |
| 675 | */ |
| 676 | static final TimeZone NO_TIMEZONE = null; |
| 677 | |
| 678 | // =======================privates=============================== |
| 679 | |
| 680 | /** |
| 681 | * The string identifier of this <code>TimeZone</code>. This is a |
| 682 | * programmatic identifier used internally to look up <code>TimeZone</code> |
| 683 | * objects from the system table and also to map them to their localized |
| 684 | * display names. <code>ID</code> values are unique in the system |
| 685 | * table but may not be for dynamically created zones. |
| 686 | * @serial |
| 687 | */ |
| 688 | private String ID; |
| 689 | private static volatile TimeZone defaultTimeZone; |
| 690 | private static final InheritableThreadLocal<TimeZone> defaultZoneTL |
| 691 | = new InheritableThreadLocal<TimeZone>(); |
| 692 | |
| 693 | static final String GMT_ID = "GMT"; |
| 694 | private static final int GMT_ID_LENGTH = 3; |
| 695 | |
| 696 | /** |
| 697 | * Parses a custom time zone identifier and returns a corresponding zone. |
| 698 | * This method doesn't support the RFC 822 time zone format. (e.g., +hhmm) |
| 699 | * |
| 700 | * @param id a string of the <a href="#CustomID">custom ID form</a>. |
| 701 | * @return a newly created TimeZone with the given offset and |
| 702 | * no daylight saving time, or null if the id cannot be parsed. |
| 703 | */ |
| 704 | private static final TimeZone parseCustomTimeZone(String id) { |
| 705 | int length; |
| 706 | |
| 707 | // Error if the length of id isn't long enough or id doesn't |
| 708 | // start with "GMT". |
| 709 | if ((length = id.length()) < (GMT_ID_LENGTH + 2) || |
| 710 | id.indexOf(GMT_ID) != 0) { |
| 711 | return null; |
| 712 | } |
| 713 | |
| 714 | ZoneInfo zi; |
| 715 | |
| 716 | // First, we try to find it in the cache with the given |
| 717 | // id. Even the id is not normalized, the returned ZoneInfo |
| 718 | // should have its normalized id. |
| 719 | zi = ZoneInfoFile.getZoneInfo(id); |
| 720 | if (zi != null) { |
| 721 | return zi; |
| 722 | } |
| 723 | |
| 724 | int index = GMT_ID_LENGTH; |
| 725 | boolean negative = false; |
| 726 | char c = id.charAt(index++); |
| 727 | if (c == '-') { |
| 728 | negative = true; |
| 729 | } else if (c != '+') { |
| 730 | return null; |
| 731 | } |
| 732 | |
| 733 | int hours = 0; |
| 734 | int num = 0; |
| 735 | int countDelim = 0; |
| 736 | int len = 0; |
| 737 | while (index < length) { |
| 738 | c = id.charAt(index++); |
| 739 | if (c == ':') { |
| 740 | if (countDelim > 0) { |
| 741 | return null; |
| 742 | } |
| 743 | if (len > 2) { |
| 744 | return null; |
| 745 | } |
| 746 | hours = num; |
| 747 | countDelim++; |
| 748 | num = 0; |
| 749 | len = 0; |
| 750 | continue; |
| 751 | } |
| 752 | if (c < '0' || c > '9') { |
| 753 | return null; |
| 754 | } |
| 755 | num = num * 10 + (c - '0'); |
| 756 | len++; |
| 757 | } |
| 758 | if (index != length) { |
| 759 | return null; |
| 760 | } |
| 761 | if (countDelim == 0) { |
| 762 | if (len <= 2) { |
| 763 | hours = num; |
| 764 | num = 0; |
| 765 | } else { |
| 766 | hours = num / 100; |
| 767 | num %= 100; |
| 768 | } |
| 769 | } else { |
| 770 | if (len != 2) { |
| 771 | return null; |
| 772 | } |
| 773 | } |
| 774 | if (hours > 23 || num > 59) { |
| 775 | return null; |
| 776 | } |
| 777 | int gmtOffset = (hours * 60 + num) * 60 * 1000; |
| 778 | |
| 779 | if (gmtOffset == 0) { |
| 780 | zi = ZoneInfoFile.getZoneInfo(GMT_ID); |
| 781 | if (negative) { |
| 782 | zi.setID("GMT-00:00"); |
| 783 | } else { |
| 784 | zi.setID("GMT+00:00"); |
| 785 | } |
| 786 | } else { |
| 787 | zi = ZoneInfoFile.getCustomTimeZone(id, negative ? -gmtOffset : gmtOffset); |
| 788 | } |
| 789 | return zi; |
| 790 | } |
| 791 | } |