1 /*
   2  * Copyright (c) 1996, 2017, 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  * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
  28  * (C) Copyright IBM Corp. 1996-1998 - 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.text;
  40 
  41 import java.io.IOException;
  42 import java.io.InvalidObjectException;
  43 import java.io.ObjectInputStream;
  44 import static java.text.DateFormatSymbols.*;
  45 import java.util.Calendar;
  46 import java.util.Date;
  47 import java.util.GregorianCalendar;
  48 import java.util.Locale;
  49 import java.util.Map;
  50 import java.util.SimpleTimeZone;
  51 import java.util.SortedMap;
  52 import java.util.TimeZone;
  53 import java.util.concurrent.ConcurrentHashMap;
  54 import java.util.concurrent.ConcurrentMap;
  55 import sun.util.calendar.CalendarUtils;
  56 import sun.util.calendar.ZoneInfoFile;
  57 import sun.util.locale.provider.LocaleProviderAdapter;
  58 
  59 /**
  60  * <code>SimpleDateFormat</code> is a concrete class for formatting and
  61  * parsing dates in a locale-sensitive manner. It allows for formatting
  62  * (date &rarr; text), parsing (text &rarr; date), and normalization.
  63  *
  64  * <p>
  65  * <code>SimpleDateFormat</code> allows you to start by choosing
  66  * any user-defined patterns for date-time formatting. However, you
  67  * are encouraged to create a date-time formatter with either
  68  * <code>getTimeInstance</code>, <code>getDateInstance</code>, or
  69  * <code>getDateTimeInstance</code> in <code>DateFormat</code>. Each
  70  * of these class methods can return a date/time formatter initialized
  71  * with a default format pattern. You may modify the format pattern
  72  * using the <code>applyPattern</code> methods as desired.
  73  * For more information on using these methods, see
  74  * {@link DateFormat}.
  75  *
  76  * <h3>Date and Time Patterns</h3>
  77  * <p>
  78  * Date and time formats are specified by <em>date and time pattern</em>
  79  * strings.
  80  * Within date and time pattern strings, unquoted letters from
  81  * <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to
  82  * <code>'z'</code> are interpreted as pattern letters representing the
  83  * components of a date or time string.
  84  * Text can be quoted using single quotes (<code>'</code>) to avoid
  85  * interpretation.
  86  * <code>"''"</code> represents a single quote.
  87  * All other characters are not interpreted; they're simply copied into the
  88  * output string during formatting or matched against the input string
  89  * during parsing.
  90  * <p>
  91  * The following pattern letters are defined (all other characters from
  92  * <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to
  93  * <code>'z'</code> are reserved):
  94  * <blockquote>
  95  * <table class="striped">
  96  * <caption style="display:none">Chart shows pattern letters, date/time component, presentation, and examples.</caption>
  97  * <thead>
  98  *     <tr>
  99  *         <th scope="col" style="text-align:left">Letter
 100  *         <th scope="col" style="text-align:left">Date or Time Component
 101  *         <th scope="col" style="text-align:left">Presentation
 102  *         <th scope="col" style="text-align:left">Examples
 103  * </thead>
 104  * <tbody>
 105  *     <tr>
 106  *         <th scope="row"><code>G</code>
 107  *         <td>Era designator
 108  *         <td><a href="#text">Text</a>
 109  *         <td><code>AD</code>
 110  *     <tr>
 111  *         <th scope="row"><code>y</code>
 112  *         <td>Year
 113  *         <td><a href="#year">Year</a>
 114  *         <td><code>1996</code>; <code>96</code>
 115  *     <tr>
 116  *         <th scope="row"><code>Y</code>
 117  *         <td>Week year
 118  *         <td><a href="#year">Year</a>
 119  *         <td><code>2009</code>; <code>09</code>
 120  *     <tr>
 121  *         <th scope="row"><code>M</code>
 122  *         <td>Month in year (context sensitive)
 123  *         <td><a href="#month">Month</a>
 124  *         <td><code>July</code>; <code>Jul</code>; <code>07</code>
 125  *     <tr>
 126  *         <th scope="row"><code>L</code>
 127  *         <td>Month in year (standalone form)
 128  *         <td><a href="#month">Month</a>
 129  *         <td><code>July</code>; <code>Jul</code>; <code>07</code>
 130  *     <tr>
 131  *         <th scope="row"><code>w</code>
 132  *         <td>Week in year
 133  *         <td><a href="#number">Number</a>
 134  *         <td><code>27</code>
 135  *     <tr>
 136  *         <th scope="row"><code>W</code>
 137  *         <td>Week in month
 138  *         <td><a href="#number">Number</a>
 139  *         <td><code>2</code>
 140  *     <tr>
 141  *         <th scope="row"><code>D</code>
 142  *         <td>Day in year
 143  *         <td><a href="#number">Number</a>
 144  *         <td><code>189</code>
 145  *     <tr>
 146  *         <th scope="row"><code>d</code>
 147  *         <td>Day in month
 148  *         <td><a href="#number">Number</a>
 149  *         <td><code>10</code>
 150  *     <tr>
 151  *         <th scope="row"><code>F</code>
 152  *         <td>Day of week in month
 153  *         <td><a href="#number">Number</a>
 154  *         <td><code>2</code>
 155  *     <tr>
 156  *         <th scope="row"><code>E</code>
 157  *         <td>Day name in week
 158  *         <td><a href="#text">Text</a>
 159  *         <td><code>Tuesday</code>; <code>Tue</code>
 160  *     <tr>
 161  *         <th scope="row"><code>u</code>
 162  *         <td>Day number of week (1 = Monday, ..., 7 = Sunday)
 163  *         <td><a href="#number">Number</a>
 164  *         <td><code>1</code>
 165  *     <tr>
 166  *         <th scope="row"><code>a</code>
 167  *         <td>Am/pm marker
 168  *         <td><a href="#text">Text</a>
 169  *         <td><code>PM</code>
 170  *     <tr>
 171  *         <th scope="row"><code>H</code>
 172  *         <td>Hour in day (0-23)
 173  *         <td><a href="#number">Number</a>
 174  *         <td><code>0</code>
 175  *     <tr>
 176  *         <th scope="row"><code>k</code>
 177  *         <td>Hour in day (1-24)
 178  *         <td><a href="#number">Number</a>
 179  *         <td><code>24</code>
 180  *     <tr>
 181  *         <th scope="row"><code>K</code>
 182  *         <td>Hour in am/pm (0-11)
 183  *         <td><a href="#number">Number</a>
 184  *         <td><code>0</code>
 185  *     <tr>
 186  *         <th scope="row"><code>h</code>
 187  *         <td>Hour in am/pm (1-12)
 188  *         <td><a href="#number">Number</a>
 189  *         <td><code>12</code>
 190  *     <tr>
 191  *         <th scope="row"><code>m</code>
 192  *         <td>Minute in hour
 193  *         <td><a href="#number">Number</a>
 194  *         <td><code>30</code>
 195  *     <tr>
 196  *         <th scope="row"><code>s</code>
 197  *         <td>Second in minute
 198  *         <td><a href="#number">Number</a>
 199  *         <td><code>55</code>
 200  *     <tr>
 201  *         <th scope="row"><code>S</code>
 202  *         <td>Millisecond
 203  *         <td><a href="#number">Number</a>
 204  *         <td><code>978</code>
 205  *     <tr>
 206  *         <th scope="row"><code>z</code>
 207  *         <td>Time zone
 208  *         <td><a href="#timezone">General time zone</a>
 209  *         <td><code>Pacific Standard Time</code>; <code>PST</code>; <code>GMT-08:00</code>
 210  *     <tr>
 211  *         <th scope="row"><code>Z</code>
 212  *         <td>Time zone
 213  *         <td><a href="#rfc822timezone">RFC 822 time zone</a>
 214  *         <td><code>-0800</code>
 215  *     <tr>
 216  *         <th scope="row"><code>X</code>
 217  *         <td>Time zone
 218  *         <td><a href="#iso8601timezone">ISO 8601 time zone</a>
 219  *         <td><code>-08</code>; <code>-0800</code>;  <code>-08:00</code>
 220  * </tbody>
 221  * </table>
 222  * </blockquote>
 223  * Pattern letters are usually repeated, as their number determines the
 224  * exact presentation:
 225  * <ul>
 226  * <li><strong><a id="text">Text:</a></strong>
 227  *     For formatting, if the number of pattern letters is 4 or more,
 228  *     the full form is used; otherwise a short or abbreviated form
 229  *     is used if available.
 230  *     For parsing, both forms are accepted, independent of the number
 231  *     of pattern letters.<br><br></li>
 232  * <li><strong><a id="number">Number:</a></strong>
 233  *     For formatting, the number of pattern letters is the minimum
 234  *     number of digits, and shorter numbers are zero-padded to this amount.
 235  *     For parsing, the number of pattern letters is ignored unless
 236  *     it's needed to separate two adjacent fields.<br><br></li>
 237  * <li><strong><a id="year">Year:</a></strong>
 238  *     If the formatter's {@link #getCalendar() Calendar} is the Gregorian
 239  *     calendar, the following rules are applied.<br>
 240  *     <ul>
 241  *     <li>For formatting, if the number of pattern letters is 2, the year
 242  *         is truncated to 2 digits; otherwise it is interpreted as a
 243  *         <a href="#number">number</a>.
 244  *     <li>For parsing, if the number of pattern letters is more than 2,
 245  *         the year is interpreted literally, regardless of the number of
 246  *         digits. So using the pattern "MM/dd/yyyy", "01/11/12" parses to
 247  *         Jan 11, 12 A.D.
 248  *     <li>For parsing with the abbreviated year pattern ("y" or "yy"),
 249  *         <code>SimpleDateFormat</code> must interpret the abbreviated year
 250  *         relative to some century.  It does this by adjusting dates to be
 251  *         within 80 years before and 20 years after the time the <code>SimpleDateFormat</code>
 252  *         instance is created. For example, using a pattern of "MM/dd/yy" and a
 253  *         <code>SimpleDateFormat</code> instance created on Jan 1, 1997,  the string
 254  *         "01/11/12" would be interpreted as Jan 11, 2012 while the string "05/04/64"
 255  *         would be interpreted as May 4, 1964.
 256  *         During parsing, only strings consisting of exactly two digits, as defined by
 257  *         {@link Character#isDigit(char)}, will be parsed into the default century.
 258  *         Any other numeric string, such as a one digit string, a three or more digit
 259  *         string, or a two digit string that isn't all digits (for example, "-1"), is
 260  *         interpreted literally.  So "01/02/3" or "01/02/003" are parsed, using the
 261  *         same pattern, as Jan 2, 3 AD.  Likewise, "01/02/-3" is parsed as Jan 2, 4 BC.
 262  *     </ul>
 263  *     Otherwise, calendar system specific forms are applied.
 264  *     For both formatting and parsing, if the number of pattern
 265  *     letters is 4 or more, a calendar specific {@linkplain
 266  *     Calendar#LONG long form} is used. Otherwise, a calendar
 267  *     specific {@linkplain Calendar#SHORT short or abbreviated form}
 268  *     is used.<br>
 269  *     <br>
 270  *     If week year {@code 'Y'} is specified and the {@linkplain
 271  *     #getCalendar() calendar} doesn't support any <a
 272  *     href="../util/GregorianCalendar.html#week_year"> week
 273  *     years</a>, the calendar year ({@code 'y'}) is used instead. The
 274  *     support of week years can be tested with a call to {@link
 275  *     DateFormat#getCalendar() getCalendar()}.{@link
 276  *     java.util.Calendar#isWeekDateSupported()
 277  *     isWeekDateSupported()}.<br><br></li>
 278  * <li><strong><a id="month">Month:</a></strong>
 279  *     If the number of pattern letters is 3 or more, the month is
 280  *     interpreted as <a href="#text">text</a>; otherwise,
 281  *     it is interpreted as a <a href="#number">number</a>.<br>
 282  *     <ul>
 283  *     <li>Letter <em>M</em> produces context-sensitive month names, such as the
 284  *         embedded form of names. Letter <em>M</em> is context-sensitive in the
 285  *         sense that when it is used in the standalone pattern, for example,
 286  *         "MMMM", it gives the standalone form of a month name and when it is
 287  *         used in the pattern containing other field(s), for example, "d MMMM",
 288  *         it gives the format form of a month name. For example, January in the
 289  *         Catalan language is "de gener" in the format form while it is "gener"
 290  *         in the standalone form. In this case, "MMMM" will produce "gener" and
 291  *         the month part of the "d MMMM" will produce "de gener". If a
 292  *         {@code DateFormatSymbols} has been set explicitly with constructor
 293  *         {@link #SimpleDateFormat(String,DateFormatSymbols)} or method {@link
 294  *         #setDateFormatSymbols(DateFormatSymbols)}, the month names given by
 295  *         the {@code DateFormatSymbols} are used.</li>
 296  *     <li>Letter <em>L</em> produces the standalone form of month names.</li>
 297  *     </ul>
 298  *     <br></li>
 299  * <li><strong><a id="timezone">General time zone:</a></strong>
 300  *     Time zones are interpreted as <a href="#text">text</a> if they have
 301  *     names. For time zones representing a GMT offset value, the
 302  *     following syntax is used:
 303  *     <pre>
 304  *     <a id="GMTOffsetTimeZone"><i>GMTOffsetTimeZone:</i></a>
 305  *             <code>GMT</code> <i>Sign</i> <i>Hours</i> <code>:</code> <i>Minutes</i>
 306  *     <i>Sign:</i> one of
 307  *             <code>+ -</code>
 308  *     <i>Hours:</i>
 309  *             <i>Digit</i>
 310  *             <i>Digit</i> <i>Digit</i>
 311  *     <i>Minutes:</i>
 312  *             <i>Digit</i> <i>Digit</i>
 313  *     <i>Digit:</i> one of
 314  *             <code>0 1 2 3 4 5 6 7 8 9</code></pre>
 315  *     <i>Hours</i> must be between 0 and 23, and <i>Minutes</i> must be between
 316  *     00 and 59. The format is locale independent and digits must be taken
 317  *     from the Basic Latin block of the Unicode standard.
 318  *     <p>For parsing, <a href="#rfc822timezone">RFC 822 time zones</a> are also
 319  *     accepted.<br><br></li>
 320  * <li><strong><a id="rfc822timezone">RFC 822 time zone:</a></strong>
 321  *     For formatting, the RFC 822 4-digit time zone format is used:
 322  *
 323  *     <pre>
 324  *     <i>RFC822TimeZone:</i>
 325  *             <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
 326  *     <i>TwoDigitHours:</i>
 327  *             <i>Digit Digit</i></pre>
 328  *     <i>TwoDigitHours</i> must be between 00 and 23. Other definitions
 329  *     are as for <a href="#timezone">general time zones</a>.
 330  *
 331  *     <p>For parsing, <a href="#timezone">general time zones</a> are also
 332  *     accepted.
 333  * <li><strong><a id="iso8601timezone">ISO 8601 Time zone:</a></strong>
 334  *     The number of pattern letters designates the format for both formatting
 335  *     and parsing as follows:
 336  *     <pre>
 337  *     <i>ISO8601TimeZone:</i>
 338  *             <i>OneLetterISO8601TimeZone</i>
 339  *             <i>TwoLetterISO8601TimeZone</i>
 340  *             <i>ThreeLetterISO8601TimeZone</i>
 341  *     <i>OneLetterISO8601TimeZone:</i>
 342  *             <i>Sign</i> <i>TwoDigitHours</i>
 343  *             {@code Z}
 344  *     <i>TwoLetterISO8601TimeZone:</i>
 345  *             <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
 346  *             {@code Z}
 347  *     <i>ThreeLetterISO8601TimeZone:</i>
 348  *             <i>Sign</i> <i>TwoDigitHours</i> {@code :} <i>Minutes</i>
 349  *             {@code Z}</pre>
 350  *     Other definitions are as for <a href="#timezone">general time zones</a> or
 351  *     <a href="#rfc822timezone">RFC 822 time zones</a>.
 352  *
 353  *     <p>For formatting, if the offset value from GMT is 0, {@code "Z"} is
 354  *     produced. If the number of pattern letters is 1, any fraction of an hour
 355  *     is ignored. For example, if the pattern is {@code "X"} and the time zone is
 356  *     {@code "GMT+05:30"}, {@code "+05"} is produced.
 357  *
 358  *     <p>For parsing, {@code "Z"} is parsed as the UTC time zone designator.
 359  *     <a href="#timezone">General time zones</a> are <em>not</em> accepted.
 360  *
 361  *     <p>If the number of pattern letters is 4 or more, {@link
 362  *     IllegalArgumentException} is thrown when constructing a {@code
 363  *     SimpleDateFormat} or {@linkplain #applyPattern(String) applying a
 364  *     pattern}.
 365  * </ul>
 366  * <code>SimpleDateFormat</code> also supports <em>localized date and time
 367  * pattern</em> strings. In these strings, the pattern letters described above
 368  * may be replaced with other, locale dependent, pattern letters.
 369  * <code>SimpleDateFormat</code> does not deal with the localization of text
 370  * other than the pattern letters; that's up to the client of the class.
 371  *
 372  * <h4>Examples</h4>
 373  *
 374  * The following examples show how date and time patterns are interpreted in
 375  * the U.S. locale. The given date and time are 2001-07-04 12:08:56 local time
 376  * in the U.S. Pacific Time time zone.
 377  * <blockquote>
 378  * <table class="striped">
 379  * <caption style="display:none">Examples of date and time patterns interpreted in the U.S. locale</caption>
 380  * <thead>
 381  *     <tr>
 382  *         <th scope="col" style="text-align:left">Date and Time Pattern
 383  *         <th scope="col" style="text-align:left">Result
 384  * </thead>
 385  * <tbody>
 386  *     <tr>
 387  *         <th scope="row"><code>"yyyy.MM.dd G 'at' HH:mm:ss z"</code>
 388  *         <td><code>2001.07.04 AD at 12:08:56 PDT</code>
 389  *     <tr>
 390  *         <th scope="row"><code>"EEE, MMM d, ''yy"</code>
 391  *         <td><code>Wed, Jul 4, '01</code>
 392  *     <tr>
 393  *         <th scope="row"><code>"h:mm a"</code>
 394  *         <td><code>12:08 PM</code>
 395  *     <tr>
 396  *         <th scope="row"><code>"hh 'o''clock' a, zzzz"</code>
 397  *         <td><code>12 o'clock PM, Pacific Daylight Time</code>
 398  *     <tr>
 399  *         <th scope="row"><code>"K:mm a, z"</code>
 400  *         <td><code>0:08 PM, PDT</code>
 401  *     <tr>
 402  *         <th scope="row"><code>"yyyyy.MMMMM.dd GGG hh:mm aaa"</code>
 403  *         <td><code>02001.July.04 AD 12:08 PM</code>
 404  *     <tr>
 405  *         <th scope="row"><code>"EEE, d MMM yyyy HH:mm:ss Z"</code>
 406  *         <td><code>Wed, 4 Jul 2001 12:08:56 -0700</code>
 407  *     <tr>
 408  *         <th scope="row"><code>"yyMMddHHmmssZ"</code>
 409  *         <td><code>010704120856-0700</code>
 410  *     <tr>
 411  *         <th scope="row"><code>"yyyy-MM-dd'T'HH:mm:ss.SSSZ"</code>
 412  *         <td><code>2001-07-04T12:08:56.235-0700</code>
 413  *     <tr>
 414  *         <th scope="row"><code>"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"</code>
 415  *         <td><code>2001-07-04T12:08:56.235-07:00</code>
 416  *     <tr>
 417  *         <th scope="row"><code>"YYYY-'W'ww-u"</code>
 418  *         <td><code>2001-W27-3</code>
 419  * </tbody>
 420  * </table>
 421  * </blockquote>
 422  *
 423  * <h4><a id="synchronization">Synchronization</a></h4>
 424  *
 425  * <p>
 426  * Date formats are not synchronized.
 427  * It is recommended to create separate format instances for each thread.
 428  * If multiple threads access a format concurrently, it must be synchronized
 429  * externally.
 430  *
 431  * @see          <a href="http://docs.oracle.com/javase/tutorial/i18n/format/simpleDateFormat.html">Java Tutorial</a>
 432  * @see          java.util.Calendar
 433  * @see          java.util.TimeZone
 434  * @see          DateFormat
 435  * @see          DateFormatSymbols
 436  * @author       Mark Davis, Chen-Lieh Huang, Alan Liu
 437  * @since 1.1
 438  */
 439 public class SimpleDateFormat extends DateFormat {
 440 
 441     // the official serial version ID which says cryptically
 442     // which version we're compatible with
 443     static final long serialVersionUID = 4774881970558875024L;
 444 
 445     // the internal serial version which says which version was written
 446     // - 0 (default) for version up to JDK 1.1.3
 447     // - 1 for version from JDK 1.1.4, which includes a new field
 448     static final int currentSerialVersion = 1;
 449 
 450     /**
 451      * The version of the serialized data on the stream.  Possible values:
 452      * <ul>
 453      * <li><b>0</b> or not present on stream: JDK 1.1.3.  This version
 454      * has no <code>defaultCenturyStart</code> on stream.
 455      * <li><b>1</b> JDK 1.1.4 or later.  This version adds
 456      * <code>defaultCenturyStart</code>.
 457      * </ul>
 458      * When streaming out this class, the most recent format
 459      * and the highest allowable <code>serialVersionOnStream</code>
 460      * is written.
 461      * @serial
 462      * @since 1.1.4
 463      */
 464     private int serialVersionOnStream = currentSerialVersion;
 465 
 466     /**
 467      * The pattern string of this formatter.  This is always a non-localized
 468      * pattern.  May not be null.  See class documentation for details.
 469      * @serial
 470      */
 471     private String pattern;
 472 
 473     /**
 474      * Saved numberFormat and pattern.
 475      * @see SimpleDateFormat#checkNegativeNumberExpression
 476      */
 477     private transient NumberFormat originalNumberFormat;
 478     private transient String originalNumberPattern;
 479 
 480     /**
 481      * The minus sign to be used with format and parse.
 482      */
 483     private transient char minusSign = '-';
 484 
 485     /**
 486      * True when a negative sign follows a number.
 487      * (True as default in Arabic.)
 488      */
 489     private transient boolean hasFollowingMinusSign = false;
 490 
 491     /**
 492      * True if standalone form needs to be used.
 493      */
 494     private transient boolean forceStandaloneForm = false;
 495 
 496     /**
 497      * The compiled pattern.
 498      */
 499     private transient char[] compiledPattern;
 500 
 501     /**
 502      * Tags for the compiled pattern.
 503      */
 504     private static final int TAG_QUOTE_ASCII_CHAR       = 100;
 505     private static final int TAG_QUOTE_CHARS            = 101;
 506 
 507     /**
 508      * Locale dependent digit zero.
 509      * @see #zeroPaddingNumber
 510      * @see java.text.DecimalFormatSymbols#getZeroDigit
 511      */
 512     private transient char zeroDigit;
 513 
 514     /**
 515      * The symbols used by this formatter for week names, month names,
 516      * etc.  May not be null.
 517      * @serial
 518      * @see java.text.DateFormatSymbols
 519      */
 520     private DateFormatSymbols formatData;
 521 
 522     /**
 523      * We map dates with two-digit years into the century starting at
 524      * <code>defaultCenturyStart</code>, which may be any date.  May
 525      * not be null.
 526      * @serial
 527      * @since 1.1.4
 528      */
 529     private Date defaultCenturyStart;
 530 
 531     private transient int defaultCenturyStartYear;
 532 
 533     private static final int MILLIS_PER_MINUTE = 60 * 1000;
 534 
 535     // For time zones that have no names, use strings GMT+minutes and
 536     // GMT-minutes. For instance, in France the time zone is GMT+60.
 537     private static final String GMT = "GMT";
 538 
 539     /**
 540      * Cache NumberFormat instances with Locale key.
 541      */
 542     private static final ConcurrentMap<Locale, NumberFormat> cachedNumberFormatData
 543         = new ConcurrentHashMap<>(3);
 544 
 545     /**
 546      * The Locale used to instantiate this
 547      * <code>SimpleDateFormat</code>. The value may be null if this object
 548      * has been created by an older <code>SimpleDateFormat</code> and
 549      * deserialized.
 550      *
 551      * @serial
 552      * @since 1.6
 553      */
 554     private Locale locale;
 555 
 556     /**
 557      * Indicates whether this <code>SimpleDateFormat</code> should use
 558      * the DateFormatSymbols. If true, the format and parse methods
 559      * use the DateFormatSymbols values. If false, the format and
 560      * parse methods call Calendar.getDisplayName or
 561      * Calendar.getDisplayNames.
 562      */
 563     transient boolean useDateFormatSymbols;
 564 
 565     /**
 566      * Constructs a <code>SimpleDateFormat</code> using the default pattern and
 567      * date format symbols for the default
 568      * {@link java.util.Locale.Category#FORMAT FORMAT} locale.
 569      * <b>Note:</b> This constructor may not support all locales.
 570      * For full coverage, use the factory methods in the {@link DateFormat}
 571      * class.
 572      */
 573     public SimpleDateFormat() {
 574         this("", Locale.getDefault(Locale.Category.FORMAT));
 575         applyPatternImpl(LocaleProviderAdapter.getResourceBundleBased().getLocaleResources(locale)
 576                          .getDateTimePattern(SHORT, SHORT, calendar));
 577     }
 578 
 579     /**
 580      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
 581      * the default date format symbols for the default
 582      * {@link java.util.Locale.Category#FORMAT FORMAT} locale.
 583      * <b>Note:</b> This constructor may not support all locales.
 584      * For full coverage, use the factory methods in the {@link DateFormat}
 585      * class.
 586      * <p>This is equivalent to calling
 587      * {@link #SimpleDateFormat(String, Locale)
 588      *     SimpleDateFormat(pattern, Locale.getDefault(Locale.Category.FORMAT))}.
 589      *
 590      * @see java.util.Locale#getDefault(java.util.Locale.Category)
 591      * @see java.util.Locale.Category#FORMAT
 592      * @param pattern the pattern describing the date and time format
 593      * @exception NullPointerException if the given pattern is null
 594      * @exception IllegalArgumentException if the given pattern is invalid
 595      */
 596     public SimpleDateFormat(String pattern)
 597     {
 598         this(pattern, Locale.getDefault(Locale.Category.FORMAT));
 599     }
 600 
 601     /**
 602      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
 603      * the default date format symbols for the given locale.
 604      * <b>Note:</b> This constructor may not support all locales.
 605      * For full coverage, use the factory methods in the {@link DateFormat}
 606      * class.
 607      *
 608      * @param pattern the pattern describing the date and time format
 609      * @param locale the locale whose date format symbols should be used
 610      * @exception NullPointerException if the given pattern or locale is null
 611      * @exception IllegalArgumentException if the given pattern is invalid
 612      */
 613     public SimpleDateFormat(String pattern, Locale locale)
 614     {
 615         if (pattern == null || locale == null) {
 616             throw new NullPointerException();
 617         }
 618 
 619         initializeCalendar(locale);
 620         this.pattern = pattern;
 621         this.formatData = DateFormatSymbols.getInstanceRef(locale);
 622         this.locale = locale;
 623         initialize(locale);
 624     }
 625 
 626     /**
 627      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
 628      * date format symbols.
 629      *
 630      * @param pattern the pattern describing the date and time format
 631      * @param formatSymbols the date format symbols to be used for formatting
 632      * @exception NullPointerException if the given pattern or formatSymbols is null
 633      * @exception IllegalArgumentException if the given pattern is invalid
 634      */
 635     public SimpleDateFormat(String pattern, DateFormatSymbols formatSymbols)
 636     {
 637         if (pattern == null || formatSymbols == null) {
 638             throw new NullPointerException();
 639         }
 640 
 641         this.pattern = pattern;
 642         this.formatData = (DateFormatSymbols) formatSymbols.clone();
 643         this.locale = Locale.getDefault(Locale.Category.FORMAT);
 644         initializeCalendar(this.locale);
 645         initialize(this.locale);
 646         useDateFormatSymbols = true;
 647     }
 648 
 649     /* Initialize compiledPattern and numberFormat fields */
 650     private void initialize(Locale loc) {
 651         // Verify and compile the given pattern.
 652         compiledPattern = compile(pattern);
 653 
 654         /* try the cache first */
 655         numberFormat = cachedNumberFormatData.get(loc);
 656         if (numberFormat == null) { /* cache miss */
 657             numberFormat = NumberFormat.getIntegerInstance(loc);
 658             numberFormat.setGroupingUsed(false);
 659 
 660             /* update cache */
 661             cachedNumberFormatData.putIfAbsent(loc, numberFormat);
 662         }
 663         numberFormat = (NumberFormat) numberFormat.clone();
 664 
 665         initializeDefaultCentury();
 666     }
 667 
 668     private void initializeCalendar(Locale loc) {
 669         if (calendar == null) {
 670             assert loc != null;
 671             // The format object must be constructed using the symbols for this zone.
 672             // However, the calendar should use the current default TimeZone.
 673             // If this is not contained in the locale zone strings, then the zone
 674             // will be formatted using generic GMT+/-H:MM nomenclature.
 675             calendar = Calendar.getInstance(TimeZone.getDefault(), loc);
 676         }
 677     }
 678 
 679     /**
 680      * Returns the compiled form of the given pattern. The syntax of
 681      * the compiled pattern is:
 682      * <blockquote>
 683      * CompiledPattern:
 684      *     EntryList
 685      * EntryList:
 686      *     Entry
 687      *     EntryList Entry
 688      * Entry:
 689      *     TagField
 690      *     TagField data
 691      * TagField:
 692      *     Tag Length
 693      *     TaggedData
 694      * Tag:
 695      *     pattern_char_index
 696      *     TAG_QUOTE_CHARS
 697      * Length:
 698      *     short_length
 699      *     long_length
 700      * TaggedData:
 701      *     TAG_QUOTE_ASCII_CHAR ascii_char
 702      *
 703      * </blockquote>
 704      *
 705      * where `short_length' is an 8-bit unsigned integer between 0 and
 706      * 254.  `long_length' is a sequence of an 8-bit integer 255 and a
 707      * 32-bit signed integer value which is split into upper and lower
 708      * 16-bit fields in two char's. `pattern_char_index' is an 8-bit
 709      * integer between 0 and 18. `ascii_char' is an 7-bit ASCII
 710      * character value. `data' depends on its Tag value.
 711      * <p>
 712      * If Length is short_length, Tag and short_length are packed in a
 713      * single char, as illustrated below.
 714      * <blockquote>
 715      *     char[0] = (Tag << 8) | short_length;
 716      * </blockquote>
 717      *
 718      * If Length is long_length, Tag and 255 are packed in the first
 719      * char and a 32-bit integer, as illustrated below.
 720      * <blockquote>
 721      *     char[0] = (Tag << 8) | 255;
 722      *     char[1] = (char) (long_length >>> 16);
 723      *     char[2] = (char) (long_length & 0xffff);
 724      * </blockquote>
 725      * <p>
 726      * If Tag is a pattern_char_index, its Length is the number of
 727      * pattern characters. For example, if the given pattern is
 728      * "yyyy", Tag is 1 and Length is 4, followed by no data.
 729      * <p>
 730      * If Tag is TAG_QUOTE_CHARS, its Length is the number of char's
 731      * following the TagField. For example, if the given pattern is
 732      * "'o''clock'", Length is 7 followed by a char sequence of
 733      * <code>o&nbs;'&nbs;c&nbs;l&nbs;o&nbs;c&nbs;k</code>.
 734      * <p>
 735      * TAG_QUOTE_ASCII_CHAR is a special tag and has an ASCII
 736      * character in place of Length. For example, if the given pattern
 737      * is "'o'", the TaggedData entry is
 738      * <code>((TAG_QUOTE_ASCII_CHAR&nbs;<<&nbs;8)&nbs;|&nbs;'o')</code>.
 739      *
 740      * @exception NullPointerException if the given pattern is null
 741      * @exception IllegalArgumentException if the given pattern is invalid
 742      */
 743     private char[] compile(String pattern) {
 744         int length = pattern.length();
 745         boolean inQuote = false;
 746         StringBuilder compiledCode = new StringBuilder(length * 2);
 747         StringBuilder tmpBuffer = null;
 748         int count = 0, tagcount = 0;
 749         int lastTag = -1, prevTag = -1;
 750 
 751         for (int i = 0; i < length; i++) {
 752             char c = pattern.charAt(i);
 753 
 754             if (c == '\'') {
 755                 // '' is treated as a single quote regardless of being
 756                 // in a quoted section.
 757                 if ((i + 1) < length) {
 758                     c = pattern.charAt(i + 1);
 759                     if (c == '\'') {
 760                         i++;
 761                         if (count != 0) {
 762                             encode(lastTag, count, compiledCode);
 763                             tagcount++;
 764                             prevTag = lastTag;
 765                             lastTag = -1;
 766                             count = 0;
 767                         }
 768                         if (inQuote) {
 769                             tmpBuffer.append(c);
 770                         } else {
 771                             compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));
 772                         }
 773                         continue;
 774                     }
 775                 }
 776                 if (!inQuote) {
 777                     if (count != 0) {
 778                         encode(lastTag, count, compiledCode);
 779                         tagcount++;
 780                         prevTag = lastTag;
 781                         lastTag = -1;
 782                         count = 0;
 783                     }
 784                     if (tmpBuffer == null) {
 785                         tmpBuffer = new StringBuilder(length);
 786                     } else {
 787                         tmpBuffer.setLength(0);
 788                     }
 789                     inQuote = true;
 790                 } else {
 791                     int len = tmpBuffer.length();
 792                     if (len == 1) {
 793                         char ch = tmpBuffer.charAt(0);
 794                         if (ch < 128) {
 795                             compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | ch));
 796                         } else {
 797                             compiledCode.append((char)(TAG_QUOTE_CHARS << 8 | 1));
 798                             compiledCode.append(ch);
 799                         }
 800                     } else {
 801                         encode(TAG_QUOTE_CHARS, len, compiledCode);
 802                         compiledCode.append(tmpBuffer);
 803                     }
 804                     inQuote = false;
 805                 }
 806                 continue;
 807             }
 808             if (inQuote) {
 809                 tmpBuffer.append(c);
 810                 continue;
 811             }
 812             if (!(c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z')) {
 813                 if (count != 0) {
 814                     encode(lastTag, count, compiledCode);
 815                     tagcount++;
 816                     prevTag = lastTag;
 817                     lastTag = -1;
 818                     count = 0;
 819                 }
 820                 if (c < 128) {
 821                     // In most cases, c would be a delimiter, such as ':'.
 822                     compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));
 823                 } else {
 824                     // Take any contiguous non-ASCII alphabet characters and
 825                     // put them in a single TAG_QUOTE_CHARS.
 826                     int j;
 827                     for (j = i + 1; j < length; j++) {
 828                         char d = pattern.charAt(j);
 829                         if (d == '\'' || (d >= 'a' && d <= 'z' || d >= 'A' && d <= 'Z')) {
 830                             break;
 831                         }
 832                     }
 833                     compiledCode.append((char)(TAG_QUOTE_CHARS << 8 | (j - i)));
 834                     for (; i < j; i++) {
 835                         compiledCode.append(pattern.charAt(i));
 836                     }
 837                     i--;
 838                 }
 839                 continue;
 840             }
 841 
 842             int tag;
 843             if ((tag = DateFormatSymbols.patternChars.indexOf(c)) == -1) {
 844                 throw new IllegalArgumentException("Illegal pattern character " +
 845                                                    "'" + c + "'");
 846             }
 847             if (lastTag == -1 || lastTag == tag) {
 848                 lastTag = tag;
 849                 count++;
 850                 continue;
 851             }
 852             encode(lastTag, count, compiledCode);
 853             tagcount++;
 854             prevTag = lastTag;
 855             lastTag = tag;
 856             count = 1;
 857         }
 858 
 859         if (inQuote) {
 860             throw new IllegalArgumentException("Unterminated quote");
 861         }
 862 
 863         if (count != 0) {
 864             encode(lastTag, count, compiledCode);
 865             tagcount++;
 866             prevTag = lastTag;
 867         }
 868 
 869         forceStandaloneForm = (tagcount == 1 && prevTag == PATTERN_MONTH);
 870 
 871         // Copy the compiled pattern to a char array
 872         int len = compiledCode.length();
 873         char[] r = new char[len];
 874         compiledCode.getChars(0, len, r, 0);
 875         return r;
 876     }
 877 
 878     /**
 879      * Encodes the given tag and length and puts encoded char(s) into buffer.
 880      */
 881     private static void encode(int tag, int length, StringBuilder buffer) {
 882         if (tag == PATTERN_ISO_ZONE && length >= 4) {
 883             throw new IllegalArgumentException("invalid ISO 8601 format: length=" + length);
 884         }
 885         if (length < 255) {
 886             buffer.append((char)(tag << 8 | length));
 887         } else {
 888             buffer.append((char)((tag << 8) | 0xff));
 889             buffer.append((char)(length >>> 16));
 890             buffer.append((char)(length & 0xffff));
 891         }
 892     }
 893 
 894     /* Initialize the fields we use to disambiguate ambiguous years. Separate
 895      * so we can call it from readObject().
 896      */
 897     private void initializeDefaultCentury() {
 898         calendar.setTimeInMillis(System.currentTimeMillis());
 899         calendar.add( Calendar.YEAR, -80 );
 900         parseAmbiguousDatesAsAfter(calendar.getTime());
 901     }
 902 
 903     /* Define one-century window into which to disambiguate dates using
 904      * two-digit years.
 905      */
 906     private void parseAmbiguousDatesAsAfter(Date startDate) {
 907         defaultCenturyStart = startDate;
 908         calendar.setTime(startDate);
 909         defaultCenturyStartYear = calendar.get(Calendar.YEAR);
 910     }
 911 
 912     /**
 913      * Sets the 100-year period 2-digit years will be interpreted as being in
 914      * to begin on the date the user specifies.
 915      *
 916      * @param startDate During parsing, two digit years will be placed in the range
 917      * <code>startDate</code> to <code>startDate + 100 years</code>.
 918      * @see #get2DigitYearStart
 919      * @throws NullPointerException if {@code startDate} is {@code null}.
 920      * @since 1.2
 921      */
 922     public void set2DigitYearStart(Date startDate) {
 923         parseAmbiguousDatesAsAfter(new Date(startDate.getTime()));
 924     }
 925 
 926     /**
 927      * Returns the beginning date of the 100-year period 2-digit years are interpreted
 928      * as being within.
 929      *
 930      * @return the start of the 100-year period into which two digit years are
 931      * parsed
 932      * @see #set2DigitYearStart
 933      * @since 1.2
 934      */
 935     public Date get2DigitYearStart() {
 936         return (Date) defaultCenturyStart.clone();
 937     }
 938 
 939     /**
 940      * Formats the given <code>Date</code> into a date/time string and appends
 941      * the result to the given <code>StringBuffer</code>.
 942      *
 943      * @param date the date-time value to be formatted into a date-time string.
 944      * @param toAppendTo where the new date-time text is to be appended.
 945      * @param pos keeps track on the position of the field within
 946      * the returned string. For example, given a date-time text
 947      * {@code "1996.07.10 AD at 15:08:56 PDT"}, if the given {@code fieldPosition}
 948      * is {@link DateFormat#YEAR_FIELD}, the begin index and end index of
 949      * {@code fieldPosition} will be set to 0 and 4, respectively.
 950      * Notice that if the same date-time field appears more than once in a
 951      * pattern, the {@code fieldPosition} will be set for the first occurrence
 952      * of that date-time field. For instance, formatting a {@code Date} to the
 953      * date-time string {@code "1 PM PDT (Pacific Daylight Time)"} using the
 954      * pattern {@code "h a z (zzzz)"} and the alignment field
 955      * {@link DateFormat#TIMEZONE_FIELD}, the begin index and end index of
 956      * {@code fieldPosition} will be set to 5 and 8, respectively, for the
 957      * first occurrence of the timezone pattern character {@code 'z'}.
 958      * @return the formatted date-time string.
 959      * @exception NullPointerException if any of the parameters is {@code null}.
 960      */
 961     @Override
 962     public StringBuffer format(Date date, StringBuffer toAppendTo,
 963                                FieldPosition pos)
 964     {
 965         pos.beginIndex = pos.endIndex = 0;
 966         return format(date, toAppendTo, pos.getFieldDelegate());
 967     }
 968 
 969     // Called from Format after creating a FieldDelegate
 970     private StringBuffer format(Date date, StringBuffer toAppendTo,
 971                                 FieldDelegate delegate) {
 972         // Convert input date to time field list
 973         calendar.setTime(date);
 974 
 975         boolean useDateFormatSymbols = useDateFormatSymbols();
 976 
 977         for (int i = 0; i < compiledPattern.length; ) {
 978             int tag = compiledPattern[i] >>> 8;
 979             int count = compiledPattern[i++] & 0xff;
 980             if (count == 255) {
 981                 count = compiledPattern[i++] << 16;
 982                 count |= compiledPattern[i++];
 983             }
 984 
 985             switch (tag) {
 986             case TAG_QUOTE_ASCII_CHAR:
 987                 toAppendTo.append((char)count);
 988                 break;
 989 
 990             case TAG_QUOTE_CHARS:
 991                 toAppendTo.append(compiledPattern, i, count);
 992                 i += count;
 993                 break;
 994 
 995             default:
 996                 subFormat(tag, count, delegate, toAppendTo, useDateFormatSymbols);
 997                 break;
 998             }
 999         }
1000         return toAppendTo;
1001     }
1002 
1003     /**
1004      * Formats an Object producing an <code>AttributedCharacterIterator</code>.
1005      * You can use the returned <code>AttributedCharacterIterator</code>
1006      * to build the resulting String, as well as to determine information
1007      * about the resulting String.
1008      * <p>
1009      * Each attribute key of the AttributedCharacterIterator will be of type
1010      * <code>DateFormat.Field</code>, with the corresponding attribute value
1011      * being the same as the attribute key.
1012      *
1013      * @exception NullPointerException if obj is null.
1014      * @exception IllegalArgumentException if the Format cannot format the
1015      *            given object, or if the Format's pattern string is invalid.
1016      * @param obj The object to format
1017      * @return AttributedCharacterIterator describing the formatted value.
1018      * @since 1.4
1019      */
1020     @Override
1021     public AttributedCharacterIterator formatToCharacterIterator(Object obj) {
1022         StringBuffer sb = new StringBuffer();
1023         CharacterIteratorFieldDelegate delegate = new
1024                          CharacterIteratorFieldDelegate();
1025 
1026         if (obj instanceof Date) {
1027             format((Date)obj, sb, delegate);
1028         }
1029         else if (obj instanceof Number) {
1030             format(new Date(((Number)obj).longValue()), sb, delegate);
1031         }
1032         else if (obj == null) {
1033             throw new NullPointerException(
1034                    "formatToCharacterIterator must be passed non-null object");
1035         }
1036         else {
1037             throw new IllegalArgumentException(
1038                              "Cannot format given Object as a Date");
1039         }
1040         return delegate.getIterator(sb.toString());
1041     }
1042 
1043     // Map index into pattern character string to Calendar field number
1044     private static final int[] PATTERN_INDEX_TO_CALENDAR_FIELD = {
1045         Calendar.ERA,
1046         Calendar.YEAR,
1047         Calendar.MONTH,
1048         Calendar.DATE,
1049         Calendar.HOUR_OF_DAY,
1050         Calendar.HOUR_OF_DAY,
1051         Calendar.MINUTE,
1052         Calendar.SECOND,
1053         Calendar.MILLISECOND,
1054         Calendar.DAY_OF_WEEK,
1055         Calendar.DAY_OF_YEAR,
1056         Calendar.DAY_OF_WEEK_IN_MONTH,
1057         Calendar.WEEK_OF_YEAR,
1058         Calendar.WEEK_OF_MONTH,
1059         Calendar.AM_PM,
1060         Calendar.HOUR,
1061         Calendar.HOUR,
1062         Calendar.ZONE_OFFSET,
1063         Calendar.ZONE_OFFSET,
1064         CalendarBuilder.WEEK_YEAR,         // Pseudo Calendar field
1065         CalendarBuilder.ISO_DAY_OF_WEEK,   // Pseudo Calendar field
1066         Calendar.ZONE_OFFSET,
1067         Calendar.MONTH
1068     };
1069 
1070     // Map index into pattern character string to DateFormat field number
1071     private static final int[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD = {
1072         DateFormat.ERA_FIELD,
1073         DateFormat.YEAR_FIELD,
1074         DateFormat.MONTH_FIELD,
1075         DateFormat.DATE_FIELD,
1076         DateFormat.HOUR_OF_DAY1_FIELD,
1077         DateFormat.HOUR_OF_DAY0_FIELD,
1078         DateFormat.MINUTE_FIELD,
1079         DateFormat.SECOND_FIELD,
1080         DateFormat.MILLISECOND_FIELD,
1081         DateFormat.DAY_OF_WEEK_FIELD,
1082         DateFormat.DAY_OF_YEAR_FIELD,
1083         DateFormat.DAY_OF_WEEK_IN_MONTH_FIELD,
1084         DateFormat.WEEK_OF_YEAR_FIELD,
1085         DateFormat.WEEK_OF_MONTH_FIELD,
1086         DateFormat.AM_PM_FIELD,
1087         DateFormat.HOUR1_FIELD,
1088         DateFormat.HOUR0_FIELD,
1089         DateFormat.TIMEZONE_FIELD,
1090         DateFormat.TIMEZONE_FIELD,
1091         DateFormat.YEAR_FIELD,
1092         DateFormat.DAY_OF_WEEK_FIELD,
1093         DateFormat.TIMEZONE_FIELD,
1094         DateFormat.MONTH_FIELD
1095     };
1096 
1097     // Maps from DecimalFormatSymbols index to Field constant
1098     private static final Field[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID = {
1099         Field.ERA,
1100         Field.YEAR,
1101         Field.MONTH,
1102         Field.DAY_OF_MONTH,
1103         Field.HOUR_OF_DAY1,
1104         Field.HOUR_OF_DAY0,
1105         Field.MINUTE,
1106         Field.SECOND,
1107         Field.MILLISECOND,
1108         Field.DAY_OF_WEEK,
1109         Field.DAY_OF_YEAR,
1110         Field.DAY_OF_WEEK_IN_MONTH,
1111         Field.WEEK_OF_YEAR,
1112         Field.WEEK_OF_MONTH,
1113         Field.AM_PM,
1114         Field.HOUR1,
1115         Field.HOUR0,
1116         Field.TIME_ZONE,
1117         Field.TIME_ZONE,
1118         Field.YEAR,
1119         Field.DAY_OF_WEEK,
1120         Field.TIME_ZONE,
1121         Field.MONTH
1122     };
1123 
1124     /**
1125      * Private member function that does the real date/time formatting.
1126      */
1127     private void subFormat(int patternCharIndex, int count,
1128                            FieldDelegate delegate, StringBuffer buffer,
1129                            boolean useDateFormatSymbols)
1130     {
1131         int     maxIntCount = Integer.MAX_VALUE;
1132         String  current = null;
1133         int     beginOffset = buffer.length();
1134 
1135         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1136         int value;
1137         if (field == CalendarBuilder.WEEK_YEAR) {
1138             if (calendar.isWeekDateSupported()) {
1139                 value = calendar.getWeekYear();
1140             } else {
1141                 // use calendar year 'y' instead
1142                 patternCharIndex = PATTERN_YEAR;
1143                 field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1144                 value = calendar.get(field);
1145             }
1146         } else if (field == CalendarBuilder.ISO_DAY_OF_WEEK) {
1147             value = CalendarBuilder.toISODayOfWeek(calendar.get(Calendar.DAY_OF_WEEK));
1148         } else {
1149             value = calendar.get(field);
1150         }
1151 
1152         int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1153         if (!useDateFormatSymbols && field < Calendar.ZONE_OFFSET
1154             && patternCharIndex != PATTERN_MONTH_STANDALONE) {
1155             current = calendar.getDisplayName(field, style, locale);
1156         }
1157 
1158         // Note: zeroPaddingNumber() assumes that maxDigits is either
1159         // 2 or maxIntCount. If we make any changes to this,
1160         // zeroPaddingNumber() must be fixed.
1161 
1162         switch (patternCharIndex) {
1163         case PATTERN_ERA: // 'G'
1164             if (useDateFormatSymbols) {
1165                 String[] eras = formatData.getEras();
1166                 if (value < eras.length) {
1167                     current = eras[value];
1168                 }
1169             }
1170             if (current == null) {
1171                 current = "";
1172             }
1173             break;
1174 
1175         case PATTERN_WEEK_YEAR: // 'Y'
1176         case PATTERN_YEAR:      // 'y'
1177             if (calendar instanceof GregorianCalendar) {
1178                 if (count != 2) {
1179                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1180                 } else {
1181                     zeroPaddingNumber(value, 2, 2, buffer);
1182                 } // clip 1996 to 96
1183             } else {
1184                 if (current == null) {
1185                     zeroPaddingNumber(value, style == Calendar.LONG ? 1 : count,
1186                                       maxIntCount, buffer);
1187                 }
1188             }
1189             break;
1190 
1191         case PATTERN_MONTH:            // 'M' (context seinsive)
1192             if (useDateFormatSymbols) {
1193                 String[] months;
1194                 if (count >= 4) {
1195                     months = formatData.getMonths();
1196                     current = months[value];
1197                 } else if (count == 3) {
1198                     months = formatData.getShortMonths();
1199                     current = months[value];
1200                 }
1201             } else {
1202                 if (count < 3) {
1203                     current = null;
1204                 } else if (forceStandaloneForm) {
1205                     current = calendar.getDisplayName(field, style | 0x8000, locale);
1206                     if (current == null) {
1207                         current = calendar.getDisplayName(field, style, locale);
1208                     }
1209                 }
1210             }
1211             if (current == null) {
1212                 zeroPaddingNumber(value+1, count, maxIntCount, buffer);
1213             }
1214             break;
1215 
1216         case PATTERN_MONTH_STANDALONE: // 'L'
1217             assert current == null;
1218             if (locale == null) {
1219                 String[] months;
1220                 if (count >= 4) {
1221                     months = formatData.getMonths();
1222                     current = months[value];
1223                 } else if (count == 3) {
1224                     months = formatData.getShortMonths();
1225                     current = months[value];
1226                 }
1227             } else {
1228                 if (count >= 3) {
1229                     current = calendar.getDisplayName(field, style | 0x8000, locale);
1230                 }
1231             }
1232             if (current == null) {
1233                 zeroPaddingNumber(value+1, count, maxIntCount, buffer);
1234             }
1235             break;
1236 
1237         case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
1238             if (current == null) {
1239                 if (value == 0) {
1240                     zeroPaddingNumber(calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1,
1241                                       count, maxIntCount, buffer);
1242                 } else {
1243                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1244                 }
1245             }
1246             break;
1247 
1248         case PATTERN_DAY_OF_WEEK: // 'E'
1249             if (useDateFormatSymbols) {
1250                 String[] weekdays;
1251                 if (count >= 4) {
1252                     weekdays = formatData.getWeekdays();
1253                     current = weekdays[value];
1254                 } else { // count < 4, use abbreviated form if exists
1255                     weekdays = formatData.getShortWeekdays();
1256                     current = weekdays[value];
1257                 }
1258             }
1259             break;
1260 
1261         case PATTERN_AM_PM:    // 'a'
1262             if (useDateFormatSymbols) {
1263                 String[] ampm = formatData.getAmPmStrings();
1264                 current = ampm[value];
1265             }
1266             break;
1267 
1268         case PATTERN_HOUR1:    // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
1269             if (current == null) {
1270                 if (value == 0) {
1271                     zeroPaddingNumber(calendar.getLeastMaximum(Calendar.HOUR) + 1,
1272                                       count, maxIntCount, buffer);
1273                 } else {
1274                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1275                 }
1276             }
1277             break;
1278 
1279         case PATTERN_ZONE_NAME: // 'z'
1280             if (current == null) {
1281                 if (formatData.locale == null || formatData.isZoneStringsSet) {
1282                     int zoneIndex =
1283                         formatData.getZoneIndex(calendar.getTimeZone().getID());
1284                     if (zoneIndex == -1) {
1285                         value = calendar.get(Calendar.ZONE_OFFSET) +
1286                             calendar.get(Calendar.DST_OFFSET);
1287                         buffer.append(ZoneInfoFile.toCustomID(value));
1288                     } else {
1289                         int index = (calendar.get(Calendar.DST_OFFSET) == 0) ? 1: 3;
1290                         if (count < 4) {
1291                             // Use the short name
1292                             index++;
1293                         }
1294                         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1295                         buffer.append(zoneStrings[zoneIndex][index]);
1296                     }
1297                 } else {
1298                     TimeZone tz = calendar.getTimeZone();
1299                     boolean daylight = (calendar.get(Calendar.DST_OFFSET) != 0);
1300                     int tzstyle = (count < 4 ? TimeZone.SHORT : TimeZone.LONG);
1301                     buffer.append(tz.getDisplayName(daylight, tzstyle, formatData.locale));
1302                 }
1303             }
1304             break;
1305 
1306         case PATTERN_ZONE_VALUE: // 'Z' ("-/+hhmm" form)
1307             value = (calendar.get(Calendar.ZONE_OFFSET) +
1308                      calendar.get(Calendar.DST_OFFSET)) / 60000;
1309 
1310             int width = 4;
1311             if (value >= 0) {
1312                 buffer.append('+');
1313             } else {
1314                 width++;
1315             }
1316 
1317             int num = (value / 60) * 100 + (value % 60);
1318             CalendarUtils.sprintf0d(buffer, num, width);
1319             break;
1320 
1321         case PATTERN_ISO_ZONE:   // 'X'
1322             value = calendar.get(Calendar.ZONE_OFFSET)
1323                     + calendar.get(Calendar.DST_OFFSET);
1324 
1325             if (value == 0) {
1326                 buffer.append('Z');
1327                 break;
1328             }
1329 
1330             value /=  60000;
1331             if (value >= 0) {
1332                 buffer.append('+');
1333             } else {
1334                 buffer.append('-');
1335                 value = -value;
1336             }
1337 
1338             CalendarUtils.sprintf0d(buffer, value / 60, 2);
1339             if (count == 1) {
1340                 break;
1341             }
1342 
1343             if (count == 3) {
1344                 buffer.append(':');
1345             }
1346             CalendarUtils.sprintf0d(buffer, value % 60, 2);
1347             break;
1348 
1349         default:
1350      // case PATTERN_DAY_OF_MONTH:         // 'd'
1351      // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
1352      // case PATTERN_MINUTE:               // 'm'
1353      // case PATTERN_SECOND:               // 's'
1354      // case PATTERN_MILLISECOND:          // 'S'
1355      // case PATTERN_DAY_OF_YEAR:          // 'D'
1356      // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
1357      // case PATTERN_WEEK_OF_YEAR:         // 'w'
1358      // case PATTERN_WEEK_OF_MONTH:        // 'W'
1359      // case PATTERN_HOUR0:                // 'K' eg, 11PM + 1 hour =>> 0 AM
1360      // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' pseudo field, Monday = 1, ..., Sunday = 7
1361             if (current == null) {
1362                 zeroPaddingNumber(value, count, maxIntCount, buffer);
1363             }
1364             break;
1365         } // switch (patternCharIndex)
1366 
1367         if (current != null) {
1368             buffer.append(current);
1369         }
1370 
1371         int fieldID = PATTERN_INDEX_TO_DATE_FORMAT_FIELD[patternCharIndex];
1372         Field f = PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID[patternCharIndex];
1373 
1374         delegate.formatted(fieldID, f, f, beginOffset, buffer.length(), buffer);
1375     }
1376 
1377     /**
1378      * Formats a number with the specified minimum and maximum number of digits.
1379      */
1380     private void zeroPaddingNumber(int value, int minDigits, int maxDigits, StringBuffer buffer)
1381     {
1382         // Optimization for 1, 2 and 4 digit numbers. This should
1383         // cover most cases of formatting date/time related items.
1384         // Note: This optimization code assumes that maxDigits is
1385         // either 2 or Integer.MAX_VALUE (maxIntCount in format()).
1386         try {
1387             if (zeroDigit == 0) {
1388                 zeroDigit = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getZeroDigit();
1389             }
1390             if (value >= 0) {
1391                 if (value < 100 && minDigits >= 1 && minDigits <= 2) {
1392                     if (value < 10) {
1393                         if (minDigits == 2) {
1394                             buffer.append(zeroDigit);
1395                         }
1396                         buffer.append((char)(zeroDigit + value));
1397                     } else {
1398                         buffer.append((char)(zeroDigit + value / 10));
1399                         buffer.append((char)(zeroDigit + value % 10));
1400                     }
1401                     return;
1402                 } else if (value >= 1000 && value < 10000) {
1403                     if (minDigits == 4) {
1404                         buffer.append((char)(zeroDigit + value / 1000));
1405                         value %= 1000;
1406                         buffer.append((char)(zeroDigit + value / 100));
1407                         value %= 100;
1408                         buffer.append((char)(zeroDigit + value / 10));
1409                         buffer.append((char)(zeroDigit + value % 10));
1410                         return;
1411                     }
1412                     if (minDigits == 2 && maxDigits == 2) {
1413                         zeroPaddingNumber(value % 100, 2, 2, buffer);
1414                         return;
1415                     }
1416                 }
1417             }
1418         } catch (Exception e) {
1419         }
1420 
1421         numberFormat.setMinimumIntegerDigits(minDigits);
1422         numberFormat.setMaximumIntegerDigits(maxDigits);
1423         numberFormat.format((long)value, buffer, DontCareFieldPosition.INSTANCE);
1424     }
1425 
1426 
1427     /**
1428      * Parses text from a string to produce a <code>Date</code>.
1429      * <p>
1430      * The method attempts to parse text starting at the index given by
1431      * <code>pos</code>.
1432      * If parsing succeeds, then the index of <code>pos</code> is updated
1433      * to the index after the last character used (parsing does not necessarily
1434      * use all characters up to the end of the string), and the parsed
1435      * date is returned. The updated <code>pos</code> can be used to
1436      * indicate the starting point for the next call to this method.
1437      * If an error occurs, then the index of <code>pos</code> is not
1438      * changed, the error index of <code>pos</code> is set to the index of
1439      * the character where the error occurred, and null is returned.
1440      *
1441      * <p>This parsing operation uses the {@link DateFormat#calendar
1442      * calendar} to produce a {@code Date}. All of the {@code
1443      * calendar}'s date-time fields are {@linkplain Calendar#clear()
1444      * cleared} before parsing, and the {@code calendar}'s default
1445      * values of the date-time fields are used for any missing
1446      * date-time information. For example, the year value of the
1447      * parsed {@code Date} is 1970 with {@link GregorianCalendar} if
1448      * no year value is given from the parsing operation.  The {@code
1449      * TimeZone} value may be overwritten, depending on the given
1450      * pattern and the time zone value in {@code text}. Any {@code
1451      * TimeZone} value that has previously been set by a call to
1452      * {@link #setTimeZone(java.util.TimeZone) setTimeZone} may need
1453      * to be restored for further operations.
1454      *
1455      * @param text  A <code>String</code>, part of which should be parsed.
1456      * @param pos   A <code>ParsePosition</code> object with index and error
1457      *              index information as described above.
1458      * @return A <code>Date</code> parsed from the string. In case of
1459      *         error, returns null.
1460      * @exception NullPointerException if <code>text</code> or <code>pos</code> is null.
1461      */
1462     @Override
1463     public Date parse(String text, ParsePosition pos)
1464     {
1465         checkNegativeNumberExpression();
1466 
1467         int start = pos.index;
1468         int oldStart = start;
1469         int textLength = text.length();
1470 
1471         boolean[] ambiguousYear = {false};
1472 
1473         CalendarBuilder calb = new CalendarBuilder();
1474 
1475         for (int i = 0; i < compiledPattern.length; ) {
1476             int tag = compiledPattern[i] >>> 8;
1477             int count = compiledPattern[i++] & 0xff;
1478             if (count == 255) {
1479                 count = compiledPattern[i++] << 16;
1480                 count |= compiledPattern[i++];
1481             }
1482 
1483             switch (tag) {
1484             case TAG_QUOTE_ASCII_CHAR:
1485                 if (start >= textLength || text.charAt(start) != (char)count) {
1486                     pos.index = oldStart;
1487                     pos.errorIndex = start;
1488                     return null;
1489                 }
1490                 start++;
1491                 break;
1492 
1493             case TAG_QUOTE_CHARS:
1494                 while (count-- > 0) {
1495                     if (start >= textLength || text.charAt(start) != compiledPattern[i++]) {
1496                         pos.index = oldStart;
1497                         pos.errorIndex = start;
1498                         return null;
1499                     }
1500                     start++;
1501                 }
1502                 break;
1503 
1504             default:
1505                 // Peek the next pattern to determine if we need to
1506                 // obey the number of pattern letters for
1507                 // parsing. It's required when parsing contiguous
1508                 // digit text (e.g., "20010704") with a pattern which
1509                 // has no delimiters between fields, like "yyyyMMdd".
1510                 boolean obeyCount = false;
1511 
1512                 // In Arabic, a minus sign for a negative number is put after
1513                 // the number. Even in another locale, a minus sign can be
1514                 // put after a number using DateFormat.setNumberFormat().
1515                 // If both the minus sign and the field-delimiter are '-',
1516                 // subParse() needs to determine whether a '-' after a number
1517                 // in the given text is a delimiter or is a minus sign for the
1518                 // preceding number. We give subParse() a clue based on the
1519                 // information in compiledPattern.
1520                 boolean useFollowingMinusSignAsDelimiter = false;
1521 
1522                 if (i < compiledPattern.length) {
1523                     int nextTag = compiledPattern[i] >>> 8;
1524                     int nextCount = compiledPattern[i] & 0xff;
1525                     obeyCount = shouldObeyCount(nextTag, nextCount);
1526 
1527                     if (hasFollowingMinusSign &&
1528                         (nextTag == TAG_QUOTE_ASCII_CHAR ||
1529                          nextTag == TAG_QUOTE_CHARS)) {
1530 
1531                         if (nextTag != TAG_QUOTE_ASCII_CHAR) {
1532                             nextCount = compiledPattern[i+1];
1533                         }
1534 
1535                         if (nextCount == minusSign) {
1536                             useFollowingMinusSignAsDelimiter = true;
1537                         }
1538                     }
1539                 }
1540                 start = subParse(text, start, tag, count, obeyCount,
1541                                  ambiguousYear, pos,
1542                                  useFollowingMinusSignAsDelimiter, calb);
1543                 if (start < 0) {
1544                     pos.index = oldStart;
1545                     return null;
1546                 }
1547             }
1548         }
1549 
1550         // At this point the fields of Calendar have been set.  Calendar
1551         // will fill in default values for missing fields when the time
1552         // is computed.
1553 
1554         pos.index = start;
1555 
1556         Date parsedDate;
1557         try {
1558             parsedDate = calb.establish(calendar).getTime();
1559             // If the year value is ambiguous,
1560             // then the two-digit year == the default start year
1561             if (ambiguousYear[0]) {
1562                 if (parsedDate.before(defaultCenturyStart)) {
1563                     parsedDate = calb.addYear(100).establish(calendar).getTime();
1564                 }
1565             }
1566         }
1567         // An IllegalArgumentException will be thrown by Calendar.getTime()
1568         // if any fields are out of range, e.g., MONTH == 17.
1569         catch (IllegalArgumentException e) {
1570             pos.errorIndex = start;
1571             pos.index = oldStart;
1572             return null;
1573         }
1574 
1575         return parsedDate;
1576     }
1577 
1578     /* If the next tag/pattern is a <Numeric_Field> then the parser
1579      * should consider the count of digits while parsing the contigous digits
1580      * for the current tag/pattern
1581      */
1582     private boolean shouldObeyCount(int tag, int count) {
1583         switch (tag) {
1584             case PATTERN_MONTH:
1585             case PATTERN_MONTH_STANDALONE:
1586                 return count <= 2;
1587             case PATTERN_YEAR:
1588             case PATTERN_DAY_OF_MONTH:
1589             case PATTERN_HOUR_OF_DAY1:
1590             case PATTERN_HOUR_OF_DAY0:
1591             case PATTERN_MINUTE:
1592             case PATTERN_SECOND:
1593             case PATTERN_MILLISECOND:
1594             case PATTERN_DAY_OF_YEAR:
1595             case PATTERN_DAY_OF_WEEK_IN_MONTH:
1596             case PATTERN_WEEK_OF_YEAR:
1597             case PATTERN_WEEK_OF_MONTH:
1598             case PATTERN_HOUR1:
1599             case PATTERN_HOUR0:
1600             case PATTERN_WEEK_YEAR:
1601             case PATTERN_ISO_DAY_OF_WEEK:
1602                 return true;
1603             default:
1604                 return false;
1605         }
1606     }
1607 
1608     /**
1609      * Private code-size reduction function used by subParse.
1610      * @param text the time text being parsed.
1611      * @param start where to start parsing.
1612      * @param field the date field being parsed.
1613      * @param data the string array to parsed.
1614      * @return the new start position if matching succeeded; a negative number
1615      * indicating matching failure, otherwise.
1616      */
1617     private int matchString(String text, int start, int field, String[] data, CalendarBuilder calb)
1618     {
1619         int i = 0;
1620         int count = data.length;
1621 
1622         if (field == Calendar.DAY_OF_WEEK) {
1623             i = 1;
1624         }
1625 
1626         // There may be multiple strings in the data[] array which begin with
1627         // the same prefix (e.g., Cerven and Cervenec (June and July) in Czech).
1628         // We keep track of the longest match, and return that.  Note that this
1629         // unfortunately requires us to test all array elements.
1630         int bestMatchLength = 0, bestMatch = -1;
1631         for (; i<count; ++i)
1632         {
1633             int length = data[i].length();
1634             // Always compare if we have no match yet; otherwise only compare
1635             // against potentially better matches (longer strings).
1636             if (length > bestMatchLength &&
1637                 text.regionMatches(true, start, data[i], 0, length))
1638             {
1639                 bestMatch = i;
1640                 bestMatchLength = length;
1641             }
1642         }
1643         if (bestMatch >= 0)
1644         {
1645             calb.set(field, bestMatch);
1646             return start + bestMatchLength;
1647         }
1648         return -start;
1649     }
1650 
1651     /**
1652      * Performs the same thing as matchString(String, int, int,
1653      * String[]). This method takes a Map<String, Integer> instead of
1654      * String[].
1655      */
1656     private int matchString(String text, int start, int field,
1657                             Map<String,Integer> data, CalendarBuilder calb) {
1658         if (data != null) {
1659             // TODO: make this default when it's in the spec.
1660             if (data instanceof SortedMap) {
1661                 for (String name : data.keySet()) {
1662                     if (text.regionMatches(true, start, name, 0, name.length())) {
1663                         calb.set(field, data.get(name));
1664                         return start + name.length();
1665                     }
1666                 }
1667                 return -start;
1668             }
1669 
1670             String bestMatch = null;
1671 
1672             for (String name : data.keySet()) {
1673                 int length = name.length();
1674                 if (bestMatch == null || length > bestMatch.length()) {
1675                     if (text.regionMatches(true, start, name, 0, length)) {
1676                         bestMatch = name;
1677                     }
1678                 }
1679             }
1680 
1681             if (bestMatch != null) {
1682                 calb.set(field, data.get(bestMatch));
1683                 return start + bestMatch.length();
1684             }
1685         }
1686         return -start;
1687     }
1688 
1689     private int matchZoneString(String text, int start, String[] zoneNames) {
1690         for (int i = 1; i <= 4; ++i) {
1691             // Checking long and short zones [1 & 2],
1692             // and long and short daylight [3 & 4].
1693             String zoneName = zoneNames[i];
1694             if (text.regionMatches(true, start,
1695                                    zoneName, 0, zoneName.length())) {
1696                 return i;
1697             }
1698         }
1699         return -1;
1700     }
1701 
1702     private boolean matchDSTString(String text, int start, int zoneIndex, int standardIndex,
1703                                    String[][] zoneStrings) {
1704         int index = standardIndex + 2;
1705         String zoneName  = zoneStrings[zoneIndex][index];
1706         if (text.regionMatches(true, start,
1707                                zoneName, 0, zoneName.length())) {
1708             return true;
1709         }
1710         return false;
1711     }
1712 
1713     /**
1714      * find time zone 'text' matched zoneStrings and set to internal
1715      * calendar.
1716      */
1717     private int subParseZoneString(String text, int start, CalendarBuilder calb) {
1718         boolean useSameName = false; // true if standard and daylight time use the same abbreviation.
1719         TimeZone currentTimeZone = getTimeZone();
1720 
1721         // At this point, check for named time zones by looking through
1722         // the locale data from the TimeZoneNames strings.
1723         // Want to be able to parse both short and long forms.
1724         int zoneIndex = formatData.getZoneIndex(currentTimeZone.getID());
1725         TimeZone tz = null;
1726         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1727         String[] zoneNames = null;
1728         int nameIndex = 0;
1729         if (zoneIndex != -1) {
1730             zoneNames = zoneStrings[zoneIndex];
1731             if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1732                 if (nameIndex <= 2) {
1733                     // Check if the standard name (abbr) and the daylight name are the same.
1734                     useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1735                 }
1736                 tz = TimeZone.getTimeZone(zoneNames[0]);
1737             }
1738         }
1739         if (tz == null) {
1740             zoneIndex = formatData.getZoneIndex(TimeZone.getDefault().getID());
1741             if (zoneIndex != -1) {
1742                 zoneNames = zoneStrings[zoneIndex];
1743                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1744                     if (nameIndex <= 2) {
1745                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1746                     }
1747                     tz = TimeZone.getTimeZone(zoneNames[0]);
1748                 }
1749             }
1750         }
1751 
1752         if (tz == null) {
1753             int len = zoneStrings.length;
1754             for (int i = 0; i < len; i++) {
1755                 zoneNames = zoneStrings[i];
1756                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1757                     if (nameIndex <= 2) {
1758                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1759                     }
1760                     tz = TimeZone.getTimeZone(zoneNames[0]);
1761                     break;
1762                 }
1763             }
1764         }
1765         if (tz != null) { // Matched any ?
1766             if (!tz.equals(currentTimeZone)) {
1767                 setTimeZone(tz);
1768             }
1769             // If the time zone matched uses the same name
1770             // (abbreviation) for both standard and daylight time,
1771             // let the time zone in the Calendar decide which one.
1772             //
1773             // Also if tz.getDSTSaving() returns 0 for DST, use tz to
1774             // determine the local time. (6645292)
1775             int dstAmount = (nameIndex >= 3) ? tz.getDSTSavings() : 0;
1776             if (!(useSameName || (nameIndex >= 3 && dstAmount == 0))) {
1777                 calb.clear(Calendar.ZONE_OFFSET).set(Calendar.DST_OFFSET, dstAmount);
1778             }
1779             return (start + zoneNames[nameIndex].length());
1780         }
1781         return -start;
1782     }
1783 
1784     /**
1785      * Parses numeric forms of time zone offset, such as "hh:mm", and
1786      * sets calb to the parsed value.
1787      *
1788      * @param text  the text to be parsed
1789      * @param start the character position to start parsing
1790      * @param sign  1: positive; -1: negative
1791      * @param count 0: 'Z' or "GMT+hh:mm" parsing; 1 - 3: the number of 'X's
1792      * @param colon true - colon required between hh and mm; false - no colon required
1793      * @param calb  a CalendarBuilder in which the parsed value is stored
1794      * @return updated parsed position, or its negative value to indicate a parsing error
1795      */
1796     private int subParseNumericZone(String text, int start, int sign, int count,
1797                                     boolean colon, CalendarBuilder calb) {
1798         int index = start;
1799 
1800       parse:
1801         try {
1802             char c = text.charAt(index++);
1803             // Parse hh
1804             int hours;
1805             if (!isDigit(c)) {
1806                 break parse;
1807             }
1808             hours = c - '0';
1809             c = text.charAt(index++);
1810             if (isDigit(c)) {
1811                 hours = hours * 10 + (c - '0');
1812             } else {
1813                 // If no colon in RFC 822 or 'X' (ISO), two digits are
1814                 // required.
1815                 if (count > 0 || !colon) {
1816                     break parse;
1817                 }
1818                 --index;
1819             }
1820             if (hours > 23) {
1821                 break parse;
1822             }
1823             int minutes = 0;
1824             if (count != 1) {
1825                 // Proceed with parsing mm
1826                 c = text.charAt(index++);
1827                 if (colon) {
1828                     if (c != ':') {
1829                         break parse;
1830                     }
1831                     c = text.charAt(index++);
1832                 }
1833                 if (!isDigit(c)) {
1834                     break parse;
1835                 }
1836                 minutes = c - '0';
1837                 c = text.charAt(index++);
1838                 if (!isDigit(c)) {
1839                     break parse;
1840                 }
1841                 minutes = minutes * 10 + (c - '0');
1842                 if (minutes > 59) {
1843                     break parse;
1844                 }
1845             }
1846             minutes += hours * 60;
1847             calb.set(Calendar.ZONE_OFFSET, minutes * MILLIS_PER_MINUTE * sign)
1848                 .set(Calendar.DST_OFFSET, 0);
1849             return index;
1850         } catch (IndexOutOfBoundsException e) {
1851         }
1852         return  1 - index; // -(index - 1)
1853     }
1854 
1855     private boolean isDigit(char c) {
1856         return c >= '0' && c <= '9';
1857     }
1858 
1859     /**
1860      * Private member function that converts the parsed date strings into
1861      * timeFields. Returns -start (for ParsePosition) if failed.
1862      * @param text the time text to be parsed.
1863      * @param start where to start parsing.
1864      * @param patternCharIndex the index of the pattern character.
1865      * @param count the count of a pattern character.
1866      * @param obeyCount if true, then the next field directly abuts this one,
1867      * and we should use the count to know when to stop parsing.
1868      * @param ambiguousYear return parameter; upon return, if ambiguousYear[0]
1869      * is true, then a two-digit year was parsed and may need to be readjusted.
1870      * @param origPos origPos.errorIndex is used to return an error index
1871      * at which a parse error occurred, if matching failure occurs.
1872      * @return the new start position if matching succeeded; -1 indicating
1873      * matching failure, otherwise. In case matching failure occurred,
1874      * an error index is set to origPos.errorIndex.
1875      */
1876     private int subParse(String text, int start, int patternCharIndex, int count,
1877                          boolean obeyCount, boolean[] ambiguousYear,
1878                          ParsePosition origPos,
1879                          boolean useFollowingMinusSignAsDelimiter, CalendarBuilder calb) {
1880         Number number;
1881         int value = 0;
1882         ParsePosition pos = new ParsePosition(0);
1883         pos.index = start;
1884         if (patternCharIndex == PATTERN_WEEK_YEAR && !calendar.isWeekDateSupported()) {
1885             // use calendar year 'y' instead
1886             patternCharIndex = PATTERN_YEAR;
1887         }
1888         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1889 
1890         // If there are any spaces here, skip over them.  If we hit the end
1891         // of the string, then fail.
1892         for (;;) {
1893             if (pos.index >= text.length()) {
1894                 origPos.errorIndex = start;
1895                 return -1;
1896             }
1897             char c = text.charAt(pos.index);
1898             if (c != ' ' && c != '\t') {
1899                 break;
1900             }
1901             ++pos.index;
1902         }
1903         // Remember the actual start index
1904         int actualStart = pos.index;
1905 
1906       parsing:
1907         {
1908             // We handle a few special cases here where we need to parse
1909             // a number value.  We handle further, more generic cases below.  We need
1910             // to handle some of them here because some fields require extra processing on
1911             // the parsed value.
1912             if (patternCharIndex == PATTERN_HOUR_OF_DAY1 ||
1913                 patternCharIndex == PATTERN_HOUR1 ||
1914                 (patternCharIndex == PATTERN_MONTH && count <= 2) ||
1915                 (patternCharIndex == PATTERN_MONTH_STANDALONE && count <= 2) ||
1916                 patternCharIndex == PATTERN_YEAR ||
1917                 patternCharIndex == PATTERN_WEEK_YEAR) {
1918                 // It would be good to unify this with the obeyCount logic below,
1919                 // but that's going to be difficult.
1920                 if (obeyCount) {
1921                     if ((start+count) > text.length()) {
1922                         break parsing;
1923                     }
1924                     number = numberFormat.parse(text.substring(0, start+count), pos);
1925                 } else {
1926                     number = numberFormat.parse(text, pos);
1927                 }
1928                 if (number == null) {
1929                     if (patternCharIndex != PATTERN_YEAR || calendar instanceof GregorianCalendar) {
1930                         break parsing;
1931                     }
1932                 } else {
1933                     value = number.intValue();
1934 
1935                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
1936                         (((pos.index < text.length()) &&
1937                          (text.charAt(pos.index) != minusSign)) ||
1938                          ((pos.index == text.length()) &&
1939                           (text.charAt(pos.index-1) == minusSign)))) {
1940                         value = -value;
1941                         pos.index--;
1942                     }
1943                 }
1944             }
1945 
1946             boolean useDateFormatSymbols = useDateFormatSymbols();
1947 
1948             int index;
1949             switch (patternCharIndex) {
1950             case PATTERN_ERA: // 'G'
1951                 if (useDateFormatSymbols) {
1952                     if ((index = matchString(text, start, Calendar.ERA, formatData.getEras(), calb)) > 0) {
1953                         return index;
1954                     }
1955                 } else {
1956                     Map<String, Integer> map = getDisplayNamesMap(field, locale);
1957                     if ((index = matchString(text, start, field, map, calb)) > 0) {
1958                         return index;
1959                     }
1960                 }
1961                 break parsing;
1962 
1963             case PATTERN_WEEK_YEAR: // 'Y'
1964             case PATTERN_YEAR:      // 'y'
1965                 if (!(calendar instanceof GregorianCalendar)) {
1966                     // calendar might have text representations for year values,
1967                     // such as "\u5143" in JapaneseImperialCalendar.
1968                     int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1969                     Map<String, Integer> map = calendar.getDisplayNames(field, style, locale);
1970                     if (map != null) {
1971                         if ((index = matchString(text, start, field, map, calb)) > 0) {
1972                             return index;
1973                         }
1974                     }
1975                     calb.set(field, value);
1976                     return pos.index;
1977                 }
1978 
1979                 // If there are 3 or more YEAR pattern characters, this indicates
1980                 // that the year value is to be treated literally, without any
1981                 // two-digit year adjustments (e.g., from "01" to 2001).  Otherwise
1982                 // we made adjustments to place the 2-digit year in the proper
1983                 // century, for parsed strings from "00" to "99".  Any other string
1984                 // is treated literally:  "2250", "-1", "1", "002".
1985                 if (count <= 2 && (pos.index - actualStart) == 2
1986                     && Character.isDigit(text.charAt(actualStart))
1987                     && Character.isDigit(text.charAt(actualStart + 1))) {
1988                     // Assume for example that the defaultCenturyStart is 6/18/1903.
1989                     // This means that two-digit years will be forced into the range
1990                     // 6/18/1903 to 6/17/2003.  As a result, years 00, 01, and 02
1991                     // correspond to 2000, 2001, and 2002.  Years 04, 05, etc. correspond
1992                     // to 1904, 1905, etc.  If the year is 03, then it is 2003 if the
1993                     // other fields specify a date before 6/18, or 1903 if they specify a
1994                     // date afterwards.  As a result, 03 is an ambiguous year.  All other
1995                     // two-digit years are unambiguous.
1996                     int ambiguousTwoDigitYear = defaultCenturyStartYear % 100;
1997                     ambiguousYear[0] = value == ambiguousTwoDigitYear;
1998                     value += (defaultCenturyStartYear/100)*100 +
1999                         (value < ambiguousTwoDigitYear ? 100 : 0);
2000                 }
2001                 calb.set(field, value);
2002                 return pos.index;
2003 
2004             case PATTERN_MONTH: // 'M'
2005                 if (count <= 2) // i.e., M or MM.
2006                 {
2007                     // Don't want to parse the month if it is a string
2008                     // while pattern uses numeric style: M or MM.
2009                     // [We computed 'value' above.]
2010                     calb.set(Calendar.MONTH, value - 1);
2011                     return pos.index;
2012                 }
2013 
2014                 if (useDateFormatSymbols) {
2015                     // count >= 3 // i.e., MMM or MMMM
2016                     // Want to be able to parse both short and long forms.
2017                     // Try count == 4 first:
2018                     int newStart;
2019                     if ((newStart = matchString(text, start, Calendar.MONTH,
2020                                                 formatData.getMonths(), calb)) > 0) {
2021                         return newStart;
2022                     }
2023                     // count == 4 failed, now try count == 3
2024                     if ((index = matchString(text, start, Calendar.MONTH,
2025                                              formatData.getShortMonths(), calb)) > 0) {
2026                         return index;
2027                     }
2028                 } else {
2029                     Map<String, Integer> map = getDisplayNamesMap(field, locale);
2030                     if ((index = matchString(text, start, field, map, calb)) > 0) {
2031                         return index;
2032                     }
2033                 }
2034                 break parsing;
2035 
2036             case PATTERN_MONTH_STANDALONE: // 'L'
2037                 if (count <= 2) {
2038                     // Don't want to parse the month if it is a string
2039                     // while pattern uses numeric style: L or LL
2040                     //[we computed 'value' above.]
2041                     calb.set(Calendar.MONTH, value - 1);
2042                     return pos.index;
2043                 }
2044                 Map<String, Integer> maps = getDisplayNamesMap(field, locale);
2045                 if ((index = matchString(text, start, field, maps, calb)) > 0) {
2046                     return index;
2047                 }
2048                 break parsing;
2049 
2050             case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
2051                 if (!isLenient()) {
2052                     // Validate the hour value in non-lenient
2053                     if (value < 1 || value > 24) {
2054                         break parsing;
2055                     }
2056                 }
2057                 // [We computed 'value' above.]
2058                 if (value == calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1) {
2059                     value = 0;
2060                 }
2061                 calb.set(Calendar.HOUR_OF_DAY, value);
2062                 return pos.index;
2063 
2064             case PATTERN_DAY_OF_WEEK:  // 'E'
2065                 {
2066                     if (useDateFormatSymbols) {
2067                         // Want to be able to parse both short and long forms.
2068                         // Try count == 4 (DDDD) first:
2069                         int newStart;
2070                         if ((newStart=matchString(text, start, Calendar.DAY_OF_WEEK,
2071                                                   formatData.getWeekdays(), calb)) > 0) {
2072                             return newStart;
2073                         }
2074                         // DDDD failed, now try DDD
2075                         if ((index = matchString(text, start, Calendar.DAY_OF_WEEK,
2076                                                  formatData.getShortWeekdays(), calb)) > 0) {
2077                             return index;
2078                         }
2079                     } else {
2080                         int[] styles = { Calendar.LONG, Calendar.SHORT };
2081                         for (int style : styles) {
2082                             Map<String,Integer> map = calendar.getDisplayNames(field, style, locale);
2083                             if ((index = matchString(text, start, field, map, calb)) > 0) {
2084                                 return index;
2085                             }
2086                         }
2087                     }
2088                 }
2089                 break parsing;
2090 
2091             case PATTERN_AM_PM:    // 'a'
2092                 if (useDateFormatSymbols) {
2093                     if ((index = matchString(text, start, Calendar.AM_PM,
2094                                              formatData.getAmPmStrings(), calb)) > 0) {
2095                         return index;
2096                     }
2097                 } else {
2098                     Map<String,Integer> map = getDisplayNamesMap(field, locale);
2099                     if ((index = matchString(text, start, field, map, calb)) > 0) {
2100                         return index;
2101                     }
2102                 }
2103                 break parsing;
2104 
2105             case PATTERN_HOUR1: // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
2106                 if (!isLenient()) {
2107                     // Validate the hour value in non-lenient
2108                     if (value < 1 || value > 12) {
2109                         break parsing;
2110                     }
2111                 }
2112                 // [We computed 'value' above.]
2113                 if (value == calendar.getLeastMaximum(Calendar.HOUR) + 1) {
2114                     value = 0;
2115                 }
2116                 calb.set(Calendar.HOUR, value);
2117                 return pos.index;
2118 
2119             case PATTERN_ZONE_NAME:  // 'z'
2120             case PATTERN_ZONE_VALUE: // 'Z'
2121                 {
2122                     int sign = 0;
2123                     try {
2124                         char c = text.charAt(pos.index);
2125                         if (c == '+') {
2126                             sign = 1;
2127                         } else if (c == '-') {
2128                             sign = -1;
2129                         }
2130                         if (sign == 0) {
2131                             // Try parsing a custom time zone "GMT+hh:mm" or "GMT".
2132                             if ((c == 'G' || c == 'g')
2133                                 && (text.length() - start) >= GMT.length()
2134                                 && text.regionMatches(true, start, GMT, 0, GMT.length())) {
2135                                 pos.index = start + GMT.length();
2136 
2137                                 if ((text.length() - pos.index) > 0) {
2138                                     c = text.charAt(pos.index);
2139                                     if (c == '+') {
2140                                         sign = 1;
2141                                     } else if (c == '-') {
2142                                         sign = -1;
2143                                     }
2144                                 }
2145 
2146                                 if (sign == 0) {    /* "GMT" without offset */
2147                                     calb.set(Calendar.ZONE_OFFSET, 0)
2148                                         .set(Calendar.DST_OFFSET, 0);
2149                                     return pos.index;
2150                                 }
2151 
2152                                 // Parse the rest as "hh:mm"
2153                                 int i = subParseNumericZone(text, ++pos.index,
2154                                                             sign, 0, true, calb);
2155                                 if (i > 0) {
2156                                     return i;
2157                                 }
2158                                 pos.index = -i;
2159                             } else {
2160                                 // Try parsing the text as a time zone
2161                                 // name or abbreviation.
2162                                 int i = subParseZoneString(text, pos.index, calb);
2163                                 if (i > 0) {
2164                                     return i;
2165                                 }
2166                                 pos.index = -i;
2167                             }
2168                         } else {
2169                             // Parse the rest as "hhmm" (RFC 822)
2170                             int i = subParseNumericZone(text, ++pos.index,
2171                                                         sign, 0, false, calb);
2172                             if (i > 0) {
2173                                 return i;
2174                             }
2175                             pos.index = -i;
2176                         }
2177                     } catch (IndexOutOfBoundsException e) {
2178                     }
2179                 }
2180                 break parsing;
2181 
2182             case PATTERN_ISO_ZONE:   // 'X'
2183                 {
2184                     if ((text.length() - pos.index) <= 0) {
2185                         break parsing;
2186                     }
2187 
2188                     int sign;
2189                     char c = text.charAt(pos.index);
2190                     if (c == 'Z') {
2191                         calb.set(Calendar.ZONE_OFFSET, 0).set(Calendar.DST_OFFSET, 0);
2192                         return ++pos.index;
2193                     }
2194 
2195                     // parse text as "+/-hh[[:]mm]" based on count
2196                     if (c == '+') {
2197                         sign = 1;
2198                     } else if (c == '-') {
2199                         sign = -1;
2200                     } else {
2201                         ++pos.index;
2202                         break parsing;
2203                     }
2204                     int i = subParseNumericZone(text, ++pos.index, sign, count,
2205                                                 count == 3, calb);
2206                     if (i > 0) {
2207                         return i;
2208                     }
2209                     pos.index = -i;
2210                 }
2211                 break parsing;
2212 
2213             default:
2214          // case PATTERN_DAY_OF_MONTH:         // 'd'
2215          // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
2216          // case PATTERN_MINUTE:               // 'm'
2217          // case PATTERN_SECOND:               // 's'
2218          // case PATTERN_MILLISECOND:          // 'S'
2219          // case PATTERN_DAY_OF_YEAR:          // 'D'
2220          // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
2221          // case PATTERN_WEEK_OF_YEAR:         // 'w'
2222          // case PATTERN_WEEK_OF_MONTH:        // 'W'
2223          // case PATTERN_HOUR0:                // 'K' 0-based.  eg, 11PM + 1 hour =>> 0 AM
2224          // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' (pseudo field);
2225 
2226                 // Handle "generic" fields
2227                 if (obeyCount) {
2228                     if ((start+count) > text.length()) {
2229                         break parsing;
2230                     }
2231                     number = numberFormat.parse(text.substring(0, start+count), pos);
2232                 } else {
2233                     number = numberFormat.parse(text, pos);
2234                 }
2235                 if (number != null) {
2236                     value = number.intValue();
2237 
2238                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
2239                         (((pos.index < text.length()) &&
2240                          (text.charAt(pos.index) != minusSign)) ||
2241                          ((pos.index == text.length()) &&
2242                           (text.charAt(pos.index-1) == minusSign)))) {
2243                         value = -value;
2244                         pos.index--;
2245                     }
2246 
2247                     calb.set(field, value);
2248                     return pos.index;
2249                 }
2250                 break parsing;
2251             }
2252         }
2253 
2254         // Parsing failed.
2255         origPos.errorIndex = pos.index;
2256         return -1;
2257     }
2258 
2259     /**
2260      * Returns true if the DateFormatSymbols has been set explicitly or locale
2261      * is null.
2262      */
2263     private boolean useDateFormatSymbols() {
2264         return useDateFormatSymbols || locale == null;
2265     }
2266 
2267     /**
2268      * Translates a pattern, mapping each character in the from string to the
2269      * corresponding character in the to string.
2270      *
2271      * @exception IllegalArgumentException if the given pattern is invalid
2272      */
2273     private String translatePattern(String pattern, String from, String to) {
2274         StringBuilder result = new StringBuilder();
2275         boolean inQuote = false;
2276         for (int i = 0; i < pattern.length(); ++i) {
2277             char c = pattern.charAt(i);
2278             if (inQuote) {
2279                 if (c == '\'') {
2280                     inQuote = false;
2281                 }
2282             }
2283             else {
2284                 if (c == '\'') {
2285                     inQuote = true;
2286                 } else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
2287                     int ci = from.indexOf(c);
2288                     if (ci >= 0) {
2289                         // patternChars is longer than localPatternChars due
2290                         // to serialization compatibility. The pattern letters
2291                         // unsupported by localPatternChars pass through.
2292                         if (ci < to.length()) {
2293                             c = to.charAt(ci);
2294                         }
2295                     } else {
2296                         throw new IllegalArgumentException("Illegal pattern " +
2297                                                            " character '" +
2298                                                            c + "'");
2299                     }
2300                 }
2301             }
2302             result.append(c);
2303         }
2304         if (inQuote) {
2305             throw new IllegalArgumentException("Unfinished quote in pattern");
2306         }
2307         return result.toString();
2308     }
2309 
2310     /**
2311      * Returns a pattern string describing this date format.
2312      *
2313      * @return a pattern string describing this date format.
2314      */
2315     public String toPattern() {
2316         return pattern;
2317     }
2318 
2319     /**
2320      * Returns a localized pattern string describing this date format.
2321      *
2322      * @return a localized pattern string describing this date format.
2323      */
2324     public String toLocalizedPattern() {
2325         return translatePattern(pattern,
2326                                 DateFormatSymbols.patternChars,
2327                                 formatData.getLocalPatternChars());
2328     }
2329 
2330     /**
2331      * Applies the given pattern string to this date format.
2332      *
2333      * @param pattern the new date and time pattern for this date format
2334      * @exception NullPointerException if the given pattern is null
2335      * @exception IllegalArgumentException if the given pattern is invalid
2336      */
2337     public void applyPattern(String pattern)
2338     {
2339         applyPatternImpl(pattern);
2340     }
2341 
2342     private void applyPatternImpl(String pattern) {
2343         compiledPattern = compile(pattern);
2344         this.pattern = pattern;
2345     }
2346 
2347     /**
2348      * Applies the given localized pattern string to this date format.
2349      *
2350      * @param pattern a String to be mapped to the new date and time format
2351      *        pattern for this format
2352      * @exception NullPointerException if the given pattern is null
2353      * @exception IllegalArgumentException if the given pattern is invalid
2354      */
2355     public void applyLocalizedPattern(String pattern) {
2356          String p = translatePattern(pattern,
2357                                      formatData.getLocalPatternChars(),
2358                                      DateFormatSymbols.patternChars);
2359          compiledPattern = compile(p);
2360          this.pattern = p;
2361     }
2362 
2363     /**
2364      * Gets a copy of the date and time format symbols of this date format.
2365      *
2366      * @return the date and time format symbols of this date format
2367      * @see #setDateFormatSymbols
2368      */
2369     public DateFormatSymbols getDateFormatSymbols()
2370     {
2371         return (DateFormatSymbols)formatData.clone();
2372     }
2373 
2374     /**
2375      * Sets the date and time format symbols of this date format.
2376      *
2377      * @param newFormatSymbols the new date and time format symbols
2378      * @exception NullPointerException if the given newFormatSymbols is null
2379      * @see #getDateFormatSymbols
2380      */
2381     public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
2382     {
2383         this.formatData = (DateFormatSymbols)newFormatSymbols.clone();
2384         useDateFormatSymbols = true;
2385     }
2386 
2387     /**
2388      * Creates a copy of this <code>SimpleDateFormat</code>. This also
2389      * clones the format's date format symbols.
2390      *
2391      * @return a clone of this <code>SimpleDateFormat</code>
2392      */
2393     @Override
2394     public Object clone() {
2395         SimpleDateFormat other = (SimpleDateFormat) super.clone();
2396         other.formatData = (DateFormatSymbols) formatData.clone();
2397         return other;
2398     }
2399 
2400     /**
2401      * Returns the hash code value for this <code>SimpleDateFormat</code> object.
2402      *
2403      * @return the hash code value for this <code>SimpleDateFormat</code> object.
2404      */
2405     @Override
2406     public int hashCode()
2407     {
2408         return pattern.hashCode();
2409         // just enough fields for a reasonable distribution
2410     }
2411 
2412     /**
2413      * Compares the given object with this <code>SimpleDateFormat</code> for
2414      * equality.
2415      *
2416      * @return true if the given object is equal to this
2417      * <code>SimpleDateFormat</code>
2418      */
2419     @Override
2420     public boolean equals(Object obj)
2421     {
2422         if (!super.equals(obj)) {
2423             return false; // super does class check
2424         }
2425         SimpleDateFormat that = (SimpleDateFormat) obj;
2426         return (pattern.equals(that.pattern)
2427                 && formatData.equals(that.formatData));
2428     }
2429 
2430     private static final int[] REST_OF_STYLES = {
2431         Calendar.SHORT_STANDALONE, Calendar.LONG_FORMAT, Calendar.LONG_STANDALONE,
2432     };
2433     private Map<String, Integer> getDisplayNamesMap(int field, Locale locale) {
2434         Map<String, Integer> map = calendar.getDisplayNames(field, Calendar.SHORT_FORMAT, locale);
2435         // Get all SHORT and LONG styles (avoid NARROW styles).
2436         for (int style : REST_OF_STYLES) {
2437             Map<String, Integer> m = calendar.getDisplayNames(field, style, locale);
2438             if (m != null) {
2439                 map.putAll(m);
2440             }
2441         }
2442         return map;
2443     }
2444 
2445     /**
2446      * After reading an object from the input stream, the format
2447      * pattern in the object is verified.
2448      *
2449      * @exception InvalidObjectException if the pattern is invalid
2450      */
2451     private void readObject(ObjectInputStream stream)
2452                          throws IOException, ClassNotFoundException {
2453         stream.defaultReadObject();
2454 
2455         try {
2456             compiledPattern = compile(pattern);
2457         } catch (Exception e) {
2458             throw new InvalidObjectException("invalid pattern");
2459         }
2460 
2461         if (serialVersionOnStream < 1) {
2462             // didn't have defaultCenturyStart field
2463             initializeDefaultCentury();
2464         }
2465         else {
2466             // fill in dependent transient field
2467             parseAmbiguousDatesAsAfter(defaultCenturyStart);
2468         }
2469         serialVersionOnStream = currentSerialVersion;
2470 
2471         // If the deserialized object has a SimpleTimeZone, try
2472         // to replace it with a ZoneInfo equivalent in order to
2473         // be compatible with the SimpleTimeZone-based
2474         // implementation as much as possible.
2475         TimeZone tz = getTimeZone();
2476         if (tz instanceof SimpleTimeZone) {
2477             String id = tz.getID();
2478             TimeZone zi = TimeZone.getTimeZone(id);
2479             if (zi != null && zi.hasSameRules(tz) && zi.getID().equals(id)) {
2480                 setTimeZone(zi);
2481             }
2482         }
2483     }
2484 
2485     /**
2486      * Analyze the negative subpattern of DecimalFormat and set/update values
2487      * as necessary.
2488      */
2489     private void checkNegativeNumberExpression() {
2490         if ((numberFormat instanceof DecimalFormat) &&
2491             !numberFormat.equals(originalNumberFormat)) {
2492             String numberPattern = ((DecimalFormat)numberFormat).toPattern();
2493             if (!numberPattern.equals(originalNumberPattern)) {
2494                 hasFollowingMinusSign = false;
2495 
2496                 int separatorIndex = numberPattern.indexOf(';');
2497                 // If the negative subpattern is not absent, we have to analayze
2498                 // it in order to check if it has a following minus sign.
2499                 if (separatorIndex > -1) {
2500                     int minusIndex = numberPattern.indexOf('-', separatorIndex);
2501                     if ((minusIndex > numberPattern.lastIndexOf('0')) &&
2502                         (minusIndex > numberPattern.lastIndexOf('#'))) {
2503                         hasFollowingMinusSign = true;
2504                         minusSign = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getMinusSign();
2505                     }
2506                 }
2507                 originalNumberPattern = numberPattern;
2508             }
2509             originalNumberFormat = numberFormat;
2510         }
2511     }
2512 
2513 }