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 the formatting position. On input: an alignment field,
 946      * if desired. On output: the offsets of the alignment field.
 947      * @return the formatted date-time string.
 948      * @exception NullPointerException if any of the parameters is {@code null}.
 949      */
 950     @Override
 951     public StringBuffer format(Date date, StringBuffer toAppendTo,
 952                                FieldPosition pos)
 953     {
 954         pos.beginIndex = pos.endIndex = 0;
 955         return format(date, toAppendTo, pos.getFieldDelegate());
 956     }
 957 
 958     // Called from Format after creating a FieldDelegate
 959     private StringBuffer format(Date date, StringBuffer toAppendTo,
 960                                 FieldDelegate delegate) {
 961         // Convert input date to time field list
 962         calendar.setTime(date);
 963 
 964         boolean useDateFormatSymbols = useDateFormatSymbols();
 965 
 966         for (int i = 0; i < compiledPattern.length; ) {
 967             int tag = compiledPattern[i] >>> 8;
 968             int count = compiledPattern[i++] & 0xff;
 969             if (count == 255) {
 970                 count = compiledPattern[i++] << 16;
 971                 count |= compiledPattern[i++];
 972             }
 973 
 974             switch (tag) {
 975             case TAG_QUOTE_ASCII_CHAR:
 976                 toAppendTo.append((char)count);
 977                 break;
 978 
 979             case TAG_QUOTE_CHARS:
 980                 toAppendTo.append(compiledPattern, i, count);
 981                 i += count;
 982                 break;
 983 
 984             default:
 985                 subFormat(tag, count, delegate, toAppendTo, useDateFormatSymbols);
 986                 break;
 987             }
 988         }
 989         return toAppendTo;
 990     }
 991 
 992     /**
 993      * Formats an Object producing an <code>AttributedCharacterIterator</code>.
 994      * You can use the returned <code>AttributedCharacterIterator</code>
 995      * to build the resulting String, as well as to determine information
 996      * about the resulting String.
 997      * <p>
 998      * Each attribute key of the AttributedCharacterIterator will be of type
 999      * <code>DateFormat.Field</code>, with the corresponding attribute value
1000      * being the same as the attribute key.
1001      *
1002      * @exception NullPointerException if obj is null.
1003      * @exception IllegalArgumentException if the Format cannot format the
1004      *            given object, or if the Format's pattern string is invalid.
1005      * @param obj The object to format
1006      * @return AttributedCharacterIterator describing the formatted value.
1007      * @since 1.4
1008      */
1009     @Override
1010     public AttributedCharacterIterator formatToCharacterIterator(Object obj) {
1011         StringBuffer sb = new StringBuffer();
1012         CharacterIteratorFieldDelegate delegate = new
1013                          CharacterIteratorFieldDelegate();
1014 
1015         if (obj instanceof Date) {
1016             format((Date)obj, sb, delegate);
1017         }
1018         else if (obj instanceof Number) {
1019             format(new Date(((Number)obj).longValue()), sb, delegate);
1020         }
1021         else if (obj == null) {
1022             throw new NullPointerException(
1023                    "formatToCharacterIterator must be passed non-null object");
1024         }
1025         else {
1026             throw new IllegalArgumentException(
1027                              "Cannot format given Object as a Date");
1028         }
1029         return delegate.getIterator(sb.toString());
1030     }
1031 
1032     // Map index into pattern character string to Calendar field number
1033     private static final int[] PATTERN_INDEX_TO_CALENDAR_FIELD = {
1034         Calendar.ERA,
1035         Calendar.YEAR,
1036         Calendar.MONTH,
1037         Calendar.DATE,
1038         Calendar.HOUR_OF_DAY,
1039         Calendar.HOUR_OF_DAY,
1040         Calendar.MINUTE,
1041         Calendar.SECOND,
1042         Calendar.MILLISECOND,
1043         Calendar.DAY_OF_WEEK,
1044         Calendar.DAY_OF_YEAR,
1045         Calendar.DAY_OF_WEEK_IN_MONTH,
1046         Calendar.WEEK_OF_YEAR,
1047         Calendar.WEEK_OF_MONTH,
1048         Calendar.AM_PM,
1049         Calendar.HOUR,
1050         Calendar.HOUR,
1051         Calendar.ZONE_OFFSET,
1052         Calendar.ZONE_OFFSET,
1053         CalendarBuilder.WEEK_YEAR,         // Pseudo Calendar field
1054         CalendarBuilder.ISO_DAY_OF_WEEK,   // Pseudo Calendar field
1055         Calendar.ZONE_OFFSET,
1056         Calendar.MONTH
1057     };
1058 
1059     // Map index into pattern character string to DateFormat field number
1060     private static final int[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD = {
1061         DateFormat.ERA_FIELD,
1062         DateFormat.YEAR_FIELD,
1063         DateFormat.MONTH_FIELD,
1064         DateFormat.DATE_FIELD,
1065         DateFormat.HOUR_OF_DAY1_FIELD,
1066         DateFormat.HOUR_OF_DAY0_FIELD,
1067         DateFormat.MINUTE_FIELD,
1068         DateFormat.SECOND_FIELD,
1069         DateFormat.MILLISECOND_FIELD,
1070         DateFormat.DAY_OF_WEEK_FIELD,
1071         DateFormat.DAY_OF_YEAR_FIELD,
1072         DateFormat.DAY_OF_WEEK_IN_MONTH_FIELD,
1073         DateFormat.WEEK_OF_YEAR_FIELD,
1074         DateFormat.WEEK_OF_MONTH_FIELD,
1075         DateFormat.AM_PM_FIELD,
1076         DateFormat.HOUR1_FIELD,
1077         DateFormat.HOUR0_FIELD,
1078         DateFormat.TIMEZONE_FIELD,
1079         DateFormat.TIMEZONE_FIELD,
1080         DateFormat.YEAR_FIELD,
1081         DateFormat.DAY_OF_WEEK_FIELD,
1082         DateFormat.TIMEZONE_FIELD,
1083         DateFormat.MONTH_FIELD
1084     };
1085 
1086     // Maps from DecimalFormatSymbols index to Field constant
1087     private static final Field[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID = {
1088         Field.ERA,
1089         Field.YEAR,
1090         Field.MONTH,
1091         Field.DAY_OF_MONTH,
1092         Field.HOUR_OF_DAY1,
1093         Field.HOUR_OF_DAY0,
1094         Field.MINUTE,
1095         Field.SECOND,
1096         Field.MILLISECOND,
1097         Field.DAY_OF_WEEK,
1098         Field.DAY_OF_YEAR,
1099         Field.DAY_OF_WEEK_IN_MONTH,
1100         Field.WEEK_OF_YEAR,
1101         Field.WEEK_OF_MONTH,
1102         Field.AM_PM,
1103         Field.HOUR1,
1104         Field.HOUR0,
1105         Field.TIME_ZONE,
1106         Field.TIME_ZONE,
1107         Field.YEAR,
1108         Field.DAY_OF_WEEK,
1109         Field.TIME_ZONE,
1110         Field.MONTH
1111     };
1112 
1113     /**
1114      * Private member function that does the real date/time formatting.
1115      */
1116     private void subFormat(int patternCharIndex, int count,
1117                            FieldDelegate delegate, StringBuffer buffer,
1118                            boolean useDateFormatSymbols)
1119     {
1120         int     maxIntCount = Integer.MAX_VALUE;
1121         String  current = null;
1122         int     beginOffset = buffer.length();
1123 
1124         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1125         int value;
1126         if (field == CalendarBuilder.WEEK_YEAR) {
1127             if (calendar.isWeekDateSupported()) {
1128                 value = calendar.getWeekYear();
1129             } else {
1130                 // use calendar year 'y' instead
1131                 patternCharIndex = PATTERN_YEAR;
1132                 field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1133                 value = calendar.get(field);
1134             }
1135         } else if (field == CalendarBuilder.ISO_DAY_OF_WEEK) {
1136             value = CalendarBuilder.toISODayOfWeek(calendar.get(Calendar.DAY_OF_WEEK));
1137         } else {
1138             value = calendar.get(field);
1139         }
1140 
1141         int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1142         if (!useDateFormatSymbols && field < Calendar.ZONE_OFFSET
1143             && patternCharIndex != PATTERN_MONTH_STANDALONE) {
1144             current = calendar.getDisplayName(field, style, locale);
1145         }
1146 
1147         // Note: zeroPaddingNumber() assumes that maxDigits is either
1148         // 2 or maxIntCount. If we make any changes to this,
1149         // zeroPaddingNumber() must be fixed.
1150 
1151         switch (patternCharIndex) {
1152         case PATTERN_ERA: // 'G'
1153             if (useDateFormatSymbols) {
1154                 String[] eras = formatData.getEras();
1155                 if (value < eras.length) {
1156                     current = eras[value];
1157                 }
1158             }
1159             if (current == null) {
1160                 current = "";
1161             }
1162             break;
1163 
1164         case PATTERN_WEEK_YEAR: // 'Y'
1165         case PATTERN_YEAR:      // 'y'
1166             if (calendar instanceof GregorianCalendar) {
1167                 if (count != 2) {
1168                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1169                 } else {
1170                     zeroPaddingNumber(value, 2, 2, buffer);
1171                 } // clip 1996 to 96
1172             } else {
1173                 if (current == null) {
1174                     zeroPaddingNumber(value, style == Calendar.LONG ? 1 : count,
1175                                       maxIntCount, buffer);
1176                 }
1177             }
1178             break;
1179 
1180         case PATTERN_MONTH:            // 'M' (context seinsive)
1181             if (useDateFormatSymbols) {
1182                 String[] months;
1183                 if (count >= 4) {
1184                     months = formatData.getMonths();
1185                     current = months[value];
1186                 } else if (count == 3) {
1187                     months = formatData.getShortMonths();
1188                     current = months[value];
1189                 }
1190             } else {
1191                 if (count < 3) {
1192                     current = null;
1193                 } else if (forceStandaloneForm) {
1194                     current = calendar.getDisplayName(field, style | 0x8000, locale);
1195                     if (current == null) {
1196                         current = calendar.getDisplayName(field, style, locale);
1197                     }
1198                 }
1199             }
1200             if (current == null) {
1201                 zeroPaddingNumber(value+1, count, maxIntCount, buffer);
1202             }
1203             break;
1204 
1205         case PATTERN_MONTH_STANDALONE: // 'L'
1206             assert current == null;
1207             if (locale == null) {
1208                 String[] months;
1209                 if (count >= 4) {
1210                     months = formatData.getMonths();
1211                     current = months[value];
1212                 } else if (count == 3) {
1213                     months = formatData.getShortMonths();
1214                     current = months[value];
1215                 }
1216             } else {
1217                 if (count >= 3) {
1218                     current = calendar.getDisplayName(field, style | 0x8000, locale);
1219                 }
1220             }
1221             if (current == null) {
1222                 zeroPaddingNumber(value+1, count, maxIntCount, buffer);
1223             }
1224             break;
1225 
1226         case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
1227             if (current == null) {
1228                 if (value == 0) {
1229                     zeroPaddingNumber(calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1,
1230                                       count, maxIntCount, buffer);
1231                 } else {
1232                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1233                 }
1234             }
1235             break;
1236 
1237         case PATTERN_DAY_OF_WEEK: // 'E'
1238             if (useDateFormatSymbols) {
1239                 String[] weekdays;
1240                 if (count >= 4) {
1241                     weekdays = formatData.getWeekdays();
1242                     current = weekdays[value];
1243                 } else { // count < 4, use abbreviated form if exists
1244                     weekdays = formatData.getShortWeekdays();
1245                     current = weekdays[value];
1246                 }
1247             }
1248             break;
1249 
1250         case PATTERN_AM_PM:    // 'a'
1251             if (useDateFormatSymbols) {
1252                 String[] ampm = formatData.getAmPmStrings();
1253                 current = ampm[value];
1254             }
1255             break;
1256 
1257         case PATTERN_HOUR1:    // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
1258             if (current == null) {
1259                 if (value == 0) {
1260                     zeroPaddingNumber(calendar.getLeastMaximum(Calendar.HOUR) + 1,
1261                                       count, maxIntCount, buffer);
1262                 } else {
1263                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1264                 }
1265             }
1266             break;
1267 
1268         case PATTERN_ZONE_NAME: // 'z'
1269             if (current == null) {
1270                 if (formatData.locale == null || formatData.isZoneStringsSet) {
1271                     int zoneIndex =
1272                         formatData.getZoneIndex(calendar.getTimeZone().getID());
1273                     if (zoneIndex == -1) {
1274                         value = calendar.get(Calendar.ZONE_OFFSET) +
1275                             calendar.get(Calendar.DST_OFFSET);
1276                         buffer.append(ZoneInfoFile.toCustomID(value));
1277                     } else {
1278                         int index = (calendar.get(Calendar.DST_OFFSET) == 0) ? 1: 3;
1279                         if (count < 4) {
1280                             // Use the short name
1281                             index++;
1282                         }
1283                         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1284                         buffer.append(zoneStrings[zoneIndex][index]);
1285                     }
1286                 } else {
1287                     TimeZone tz = calendar.getTimeZone();
1288                     boolean daylight = (calendar.get(Calendar.DST_OFFSET) != 0);
1289                     int tzstyle = (count < 4 ? TimeZone.SHORT : TimeZone.LONG);
1290                     buffer.append(tz.getDisplayName(daylight, tzstyle, formatData.locale));
1291                 }
1292             }
1293             break;
1294 
1295         case PATTERN_ZONE_VALUE: // 'Z' ("-/+hhmm" form)
1296             value = (calendar.get(Calendar.ZONE_OFFSET) +
1297                      calendar.get(Calendar.DST_OFFSET)) / 60000;
1298 
1299             int width = 4;
1300             if (value >= 0) {
1301                 buffer.append('+');
1302             } else {
1303                 width++;
1304             }
1305 
1306             int num = (value / 60) * 100 + (value % 60);
1307             CalendarUtils.sprintf0d(buffer, num, width);
1308             break;
1309 
1310         case PATTERN_ISO_ZONE:   // 'X'
1311             value = calendar.get(Calendar.ZONE_OFFSET)
1312                     + calendar.get(Calendar.DST_OFFSET);
1313 
1314             if (value == 0) {
1315                 buffer.append('Z');
1316                 break;
1317             }
1318 
1319             value /=  60000;
1320             if (value >= 0) {
1321                 buffer.append('+');
1322             } else {
1323                 buffer.append('-');
1324                 value = -value;
1325             }
1326 
1327             CalendarUtils.sprintf0d(buffer, value / 60, 2);
1328             if (count == 1) {
1329                 break;
1330             }
1331 
1332             if (count == 3) {
1333                 buffer.append(':');
1334             }
1335             CalendarUtils.sprintf0d(buffer, value % 60, 2);
1336             break;
1337 
1338         default:
1339      // case PATTERN_DAY_OF_MONTH:         // 'd'
1340      // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
1341      // case PATTERN_MINUTE:               // 'm'
1342      // case PATTERN_SECOND:               // 's'
1343      // case PATTERN_MILLISECOND:          // 'S'
1344      // case PATTERN_DAY_OF_YEAR:          // 'D'
1345      // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
1346      // case PATTERN_WEEK_OF_YEAR:         // 'w'
1347      // case PATTERN_WEEK_OF_MONTH:        // 'W'
1348      // case PATTERN_HOUR0:                // 'K' eg, 11PM + 1 hour =>> 0 AM
1349      // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' pseudo field, Monday = 1, ..., Sunday = 7
1350             if (current == null) {
1351                 zeroPaddingNumber(value, count, maxIntCount, buffer);
1352             }
1353             break;
1354         } // switch (patternCharIndex)
1355 
1356         if (current != null) {
1357             buffer.append(current);
1358         }
1359 
1360         int fieldID = PATTERN_INDEX_TO_DATE_FORMAT_FIELD[patternCharIndex];
1361         Field f = PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID[patternCharIndex];
1362 
1363         delegate.formatted(fieldID, f, f, beginOffset, buffer.length(), buffer);
1364     }
1365 
1366     /**
1367      * Formats a number with the specified minimum and maximum number of digits.
1368      */
1369     private void zeroPaddingNumber(int value, int minDigits, int maxDigits, StringBuffer buffer)
1370     {
1371         // Optimization for 1, 2 and 4 digit numbers. This should
1372         // cover most cases of formatting date/time related items.
1373         // Note: This optimization code assumes that maxDigits is
1374         // either 2 or Integer.MAX_VALUE (maxIntCount in format()).
1375         try {
1376             if (zeroDigit == 0) {
1377                 zeroDigit = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getZeroDigit();
1378             }
1379             if (value >= 0) {
1380                 if (value < 100 && minDigits >= 1 && minDigits <= 2) {
1381                     if (value < 10) {
1382                         if (minDigits == 2) {
1383                             buffer.append(zeroDigit);
1384                         }
1385                         buffer.append((char)(zeroDigit + value));
1386                     } else {
1387                         buffer.append((char)(zeroDigit + value / 10));
1388                         buffer.append((char)(zeroDigit + value % 10));
1389                     }
1390                     return;
1391                 } else if (value >= 1000 && value < 10000) {
1392                     if (minDigits == 4) {
1393                         buffer.append((char)(zeroDigit + value / 1000));
1394                         value %= 1000;
1395                         buffer.append((char)(zeroDigit + value / 100));
1396                         value %= 100;
1397                         buffer.append((char)(zeroDigit + value / 10));
1398                         buffer.append((char)(zeroDigit + value % 10));
1399                         return;
1400                     }
1401                     if (minDigits == 2 && maxDigits == 2) {
1402                         zeroPaddingNumber(value % 100, 2, 2, buffer);
1403                         return;
1404                     }
1405                 }
1406             }
1407         } catch (Exception e) {
1408         }
1409 
1410         numberFormat.setMinimumIntegerDigits(minDigits);
1411         numberFormat.setMaximumIntegerDigits(maxDigits);
1412         numberFormat.format((long)value, buffer, DontCareFieldPosition.INSTANCE);
1413     }
1414 
1415 
1416     /**
1417      * Parses text from a string to produce a <code>Date</code>.
1418      * <p>
1419      * The method attempts to parse text starting at the index given by
1420      * <code>pos</code>.
1421      * If parsing succeeds, then the index of <code>pos</code> is updated
1422      * to the index after the last character used (parsing does not necessarily
1423      * use all characters up to the end of the string), and the parsed
1424      * date is returned. The updated <code>pos</code> can be used to
1425      * indicate the starting point for the next call to this method.
1426      * If an error occurs, then the index of <code>pos</code> is not
1427      * changed, the error index of <code>pos</code> is set to the index of
1428      * the character where the error occurred, and null is returned.
1429      *
1430      * <p>This parsing operation uses the {@link DateFormat#calendar
1431      * calendar} to produce a {@code Date}. All of the {@code
1432      * calendar}'s date-time fields are {@linkplain Calendar#clear()
1433      * cleared} before parsing, and the {@code calendar}'s default
1434      * values of the date-time fields are used for any missing
1435      * date-time information. For example, the year value of the
1436      * parsed {@code Date} is 1970 with {@link GregorianCalendar} if
1437      * no year value is given from the parsing operation.  The {@code
1438      * TimeZone} value may be overwritten, depending on the given
1439      * pattern and the time zone value in {@code text}. Any {@code
1440      * TimeZone} value that has previously been set by a call to
1441      * {@link #setTimeZone(java.util.TimeZone) setTimeZone} may need
1442      * to be restored for further operations.
1443      *
1444      * @param text  A <code>String</code>, part of which should be parsed.
1445      * @param pos   A <code>ParsePosition</code> object with index and error
1446      *              index information as described above.
1447      * @return A <code>Date</code> parsed from the string. In case of
1448      *         error, returns null.
1449      * @exception NullPointerException if <code>text</code> or <code>pos</code> is null.
1450      */
1451     @Override
1452     public Date parse(String text, ParsePosition pos)
1453     {
1454         checkNegativeNumberExpression();
1455 
1456         int start = pos.index;
1457         int oldStart = start;
1458         int textLength = text.length();
1459 
1460         boolean[] ambiguousYear = {false};
1461 
1462         CalendarBuilder calb = new CalendarBuilder();
1463 
1464         for (int i = 0; i < compiledPattern.length; ) {
1465             int tag = compiledPattern[i] >>> 8;
1466             int count = compiledPattern[i++] & 0xff;
1467             if (count == 255) {
1468                 count = compiledPattern[i++] << 16;
1469                 count |= compiledPattern[i++];
1470             }
1471 
1472             switch (tag) {
1473             case TAG_QUOTE_ASCII_CHAR:
1474                 if (start >= textLength || text.charAt(start) != (char)count) {
1475                     pos.index = oldStart;
1476                     pos.errorIndex = start;
1477                     return null;
1478                 }
1479                 start++;
1480                 break;
1481 
1482             case TAG_QUOTE_CHARS:
1483                 while (count-- > 0) {
1484                     if (start >= textLength || text.charAt(start) != compiledPattern[i++]) {
1485                         pos.index = oldStart;
1486                         pos.errorIndex = start;
1487                         return null;
1488                     }
1489                     start++;
1490                 }
1491                 break;
1492 
1493             default:
1494                 // Peek the next pattern to determine if we need to
1495                 // obey the number of pattern letters for
1496                 // parsing. It's required when parsing contiguous
1497                 // digit text (e.g., "20010704") with a pattern which
1498                 // has no delimiters between fields, like "yyyyMMdd".
1499                 boolean obeyCount = false;
1500 
1501                 // In Arabic, a minus sign for a negative number is put after
1502                 // the number. Even in another locale, a minus sign can be
1503                 // put after a number using DateFormat.setNumberFormat().
1504                 // If both the minus sign and the field-delimiter are '-',
1505                 // subParse() needs to determine whether a '-' after a number
1506                 // in the given text is a delimiter or is a minus sign for the
1507                 // preceding number. We give subParse() a clue based on the
1508                 // information in compiledPattern.
1509                 boolean useFollowingMinusSignAsDelimiter = false;
1510 
1511                 if (i < compiledPattern.length) {
1512                     int nextTag = compiledPattern[i] >>> 8;
1513                     int nextCount = compiledPattern[i] & 0xff;
1514                     obeyCount = shouldObeyCount(nextTag, nextCount);
1515 
1516                     if (hasFollowingMinusSign &&
1517                         (nextTag == TAG_QUOTE_ASCII_CHAR ||
1518                          nextTag == TAG_QUOTE_CHARS)) {
1519 
1520                         if (nextTag != TAG_QUOTE_ASCII_CHAR) {
1521                             nextCount = compiledPattern[i+1];
1522                         }
1523 
1524                         if (nextCount == minusSign) {
1525                             useFollowingMinusSignAsDelimiter = true;
1526                         }
1527                     }
1528                 }
1529                 start = subParse(text, start, tag, count, obeyCount,
1530                                  ambiguousYear, pos,
1531                                  useFollowingMinusSignAsDelimiter, calb);
1532                 if (start < 0) {
1533                     pos.index = oldStart;
1534                     return null;
1535                 }
1536             }
1537         }
1538 
1539         // At this point the fields of Calendar have been set.  Calendar
1540         // will fill in default values for missing fields when the time
1541         // is computed.
1542 
1543         pos.index = start;
1544 
1545         Date parsedDate;
1546         try {
1547             parsedDate = calb.establish(calendar).getTime();
1548             // If the year value is ambiguous,
1549             // then the two-digit year == the default start year
1550             if (ambiguousYear[0]) {
1551                 if (parsedDate.before(defaultCenturyStart)) {
1552                     parsedDate = calb.addYear(100).establish(calendar).getTime();
1553                 }
1554             }
1555         }
1556         // An IllegalArgumentException will be thrown by Calendar.getTime()
1557         // if any fields are out of range, e.g., MONTH == 17.
1558         catch (IllegalArgumentException e) {
1559             pos.errorIndex = start;
1560             pos.index = oldStart;
1561             return null;
1562         }
1563 
1564         return parsedDate;
1565     }
1566 
1567     /* If the next tag/pattern is a <Numeric_Field> then the parser
1568      * should consider the count of digits while parsing the contigous digits
1569      * for the current tag/pattern
1570      */
1571     private boolean shouldObeyCount(int tag, int count) {
1572         switch (tag) {
1573             case PATTERN_MONTH:
1574             case PATTERN_MONTH_STANDALONE:
1575                 return count <= 2;
1576             case PATTERN_YEAR:
1577             case PATTERN_DAY_OF_MONTH:
1578             case PATTERN_HOUR_OF_DAY1:
1579             case PATTERN_HOUR_OF_DAY0:
1580             case PATTERN_MINUTE:
1581             case PATTERN_SECOND:
1582             case PATTERN_MILLISECOND:
1583             case PATTERN_DAY_OF_YEAR:
1584             case PATTERN_DAY_OF_WEEK_IN_MONTH:
1585             case PATTERN_WEEK_OF_YEAR:
1586             case PATTERN_WEEK_OF_MONTH:
1587             case PATTERN_HOUR1:
1588             case PATTERN_HOUR0:
1589             case PATTERN_WEEK_YEAR:
1590             case PATTERN_ISO_DAY_OF_WEEK:
1591                 return true;
1592             default:
1593                 return false;
1594         }
1595     }
1596 
1597     /**
1598      * Private code-size reduction function used by subParse.
1599      * @param text the time text being parsed.
1600      * @param start where to start parsing.
1601      * @param field the date field being parsed.
1602      * @param data the string array to parsed.
1603      * @return the new start position if matching succeeded; a negative number
1604      * indicating matching failure, otherwise.
1605      */
1606     private int matchString(String text, int start, int field, String[] data, CalendarBuilder calb)
1607     {
1608         int i = 0;
1609         int count = data.length;
1610 
1611         if (field == Calendar.DAY_OF_WEEK) {
1612             i = 1;
1613         }
1614 
1615         // There may be multiple strings in the data[] array which begin with
1616         // the same prefix (e.g., Cerven and Cervenec (June and July) in Czech).
1617         // We keep track of the longest match, and return that.  Note that this
1618         // unfortunately requires us to test all array elements.
1619         int bestMatchLength = 0, bestMatch = -1;
1620         for (; i<count; ++i)
1621         {
1622             int length = data[i].length();
1623             // Always compare if we have no match yet; otherwise only compare
1624             // against potentially better matches (longer strings).
1625             if (length > bestMatchLength &&
1626                 text.regionMatches(true, start, data[i], 0, length))
1627             {
1628                 bestMatch = i;
1629                 bestMatchLength = length;
1630             }
1631         }
1632         if (bestMatch >= 0)
1633         {
1634             calb.set(field, bestMatch);
1635             return start + bestMatchLength;
1636         }
1637         return -start;
1638     }
1639 
1640     /**
1641      * Performs the same thing as matchString(String, int, int,
1642      * String[]). This method takes a Map<String, Integer> instead of
1643      * String[].
1644      */
1645     private int matchString(String text, int start, int field,
1646                             Map<String,Integer> data, CalendarBuilder calb) {
1647         if (data != null) {
1648             // TODO: make this default when it's in the spec.
1649             if (data instanceof SortedMap) {
1650                 for (String name : data.keySet()) {
1651                     if (text.regionMatches(true, start, name, 0, name.length())) {
1652                         calb.set(field, data.get(name));
1653                         return start + name.length();
1654                     }
1655                 }
1656                 return -start;
1657             }
1658 
1659             String bestMatch = null;
1660 
1661             for (String name : data.keySet()) {
1662                 int length = name.length();
1663                 if (bestMatch == null || length > bestMatch.length()) {
1664                     if (text.regionMatches(true, start, name, 0, length)) {
1665                         bestMatch = name;
1666                     }
1667                 }
1668             }
1669 
1670             if (bestMatch != null) {
1671                 calb.set(field, data.get(bestMatch));
1672                 return start + bestMatch.length();
1673             }
1674         }
1675         return -start;
1676     }
1677 
1678     private int matchZoneString(String text, int start, String[] zoneNames) {
1679         for (int i = 1; i <= 4; ++i) {
1680             // Checking long and short zones [1 & 2],
1681             // and long and short daylight [3 & 4].
1682             String zoneName = zoneNames[i];
1683             if (text.regionMatches(true, start,
1684                                    zoneName, 0, zoneName.length())) {
1685                 return i;
1686             }
1687         }
1688         return -1;
1689     }
1690 
1691     private boolean matchDSTString(String text, int start, int zoneIndex, int standardIndex,
1692                                    String[][] zoneStrings) {
1693         int index = standardIndex + 2;
1694         String zoneName  = zoneStrings[zoneIndex][index];
1695         if (text.regionMatches(true, start,
1696                                zoneName, 0, zoneName.length())) {
1697             return true;
1698         }
1699         return false;
1700     }
1701 
1702     /**
1703      * find time zone 'text' matched zoneStrings and set to internal
1704      * calendar.
1705      */
1706     private int subParseZoneString(String text, int start, CalendarBuilder calb) {
1707         boolean useSameName = false; // true if standard and daylight time use the same abbreviation.
1708         TimeZone currentTimeZone = getTimeZone();
1709 
1710         // At this point, check for named time zones by looking through
1711         // the locale data from the TimeZoneNames strings.
1712         // Want to be able to parse both short and long forms.
1713         int zoneIndex = formatData.getZoneIndex(currentTimeZone.getID());
1714         TimeZone tz = null;
1715         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1716         String[] zoneNames = null;
1717         int nameIndex = 0;
1718         if (zoneIndex != -1) {
1719             zoneNames = zoneStrings[zoneIndex];
1720             if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1721                 if (nameIndex <= 2) {
1722                     // Check if the standard name (abbr) and the daylight name are the same.
1723                     useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1724                 }
1725                 tz = TimeZone.getTimeZone(zoneNames[0]);
1726             }
1727         }
1728         if (tz == null) {
1729             zoneIndex = formatData.getZoneIndex(TimeZone.getDefault().getID());
1730             if (zoneIndex != -1) {
1731                 zoneNames = zoneStrings[zoneIndex];
1732                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1733                     if (nameIndex <= 2) {
1734                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1735                     }
1736                     tz = TimeZone.getTimeZone(zoneNames[0]);
1737                 }
1738             }
1739         }
1740 
1741         if (tz == null) {
1742             int len = zoneStrings.length;
1743             for (int i = 0; i < len; i++) {
1744                 zoneNames = zoneStrings[i];
1745                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1746                     if (nameIndex <= 2) {
1747                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1748                     }
1749                     tz = TimeZone.getTimeZone(zoneNames[0]);
1750                     break;
1751                 }
1752             }
1753         }
1754         if (tz != null) { // Matched any ?
1755             if (!tz.equals(currentTimeZone)) {
1756                 setTimeZone(tz);
1757             }
1758             // If the time zone matched uses the same name
1759             // (abbreviation) for both standard and daylight time,
1760             // let the time zone in the Calendar decide which one.
1761             //
1762             // Also if tz.getDSTSaving() returns 0 for DST, use tz to
1763             // determine the local time. (6645292)
1764             int dstAmount = (nameIndex >= 3) ? tz.getDSTSavings() : 0;
1765             if (!(useSameName || (nameIndex >= 3 && dstAmount == 0))) {
1766                 calb.clear(Calendar.ZONE_OFFSET).set(Calendar.DST_OFFSET, dstAmount);
1767             }
1768             return (start + zoneNames[nameIndex].length());
1769         }
1770         return -start;
1771     }
1772 
1773     /**
1774      * Parses numeric forms of time zone offset, such as "hh:mm", and
1775      * sets calb to the parsed value.
1776      *
1777      * @param text  the text to be parsed
1778      * @param start the character position to start parsing
1779      * @param sign  1: positive; -1: negative
1780      * @param count 0: 'Z' or "GMT+hh:mm" parsing; 1 - 3: the number of 'X's
1781      * @param colon true - colon required between hh and mm; false - no colon required
1782      * @param calb  a CalendarBuilder in which the parsed value is stored
1783      * @return updated parsed position, or its negative value to indicate a parsing error
1784      */
1785     private int subParseNumericZone(String text, int start, int sign, int count,
1786                                     boolean colon, CalendarBuilder calb) {
1787         int index = start;
1788 
1789       parse:
1790         try {
1791             char c = text.charAt(index++);
1792             // Parse hh
1793             int hours;
1794             if (!isDigit(c)) {
1795                 break parse;
1796             }
1797             hours = c - '0';
1798             c = text.charAt(index++);
1799             if (isDigit(c)) {
1800                 hours = hours * 10 + (c - '0');
1801             } else {
1802                 // If no colon in RFC 822 or 'X' (ISO), two digits are
1803                 // required.
1804                 if (count > 0 || !colon) {
1805                     break parse;
1806                 }
1807                 --index;
1808             }
1809             if (hours > 23) {
1810                 break parse;
1811             }
1812             int minutes = 0;
1813             if (count != 1) {
1814                 // Proceed with parsing mm
1815                 c = text.charAt(index++);
1816                 if (colon) {
1817                     if (c != ':') {
1818                         break parse;
1819                     }
1820                     c = text.charAt(index++);
1821                 }
1822                 if (!isDigit(c)) {
1823                     break parse;
1824                 }
1825                 minutes = c - '0';
1826                 c = text.charAt(index++);
1827                 if (!isDigit(c)) {
1828                     break parse;
1829                 }
1830                 minutes = minutes * 10 + (c - '0');
1831                 if (minutes > 59) {
1832                     break parse;
1833                 }
1834             }
1835             minutes += hours * 60;
1836             calb.set(Calendar.ZONE_OFFSET, minutes * MILLIS_PER_MINUTE * sign)
1837                 .set(Calendar.DST_OFFSET, 0);
1838             return index;
1839         } catch (IndexOutOfBoundsException e) {
1840         }
1841         return  1 - index; // -(index - 1)
1842     }
1843 
1844     private boolean isDigit(char c) {
1845         return c >= '0' && c <= '9';
1846     }
1847 
1848     /**
1849      * Private member function that converts the parsed date strings into
1850      * timeFields. Returns -start (for ParsePosition) if failed.
1851      * @param text the time text to be parsed.
1852      * @param start where to start parsing.
1853      * @param patternCharIndex the index of the pattern character.
1854      * @param count the count of a pattern character.
1855      * @param obeyCount if true, then the next field directly abuts this one,
1856      * and we should use the count to know when to stop parsing.
1857      * @param ambiguousYear return parameter; upon return, if ambiguousYear[0]
1858      * is true, then a two-digit year was parsed and may need to be readjusted.
1859      * @param origPos origPos.errorIndex is used to return an error index
1860      * at which a parse error occurred, if matching failure occurs.
1861      * @return the new start position if matching succeeded; -1 indicating
1862      * matching failure, otherwise. In case matching failure occurred,
1863      * an error index is set to origPos.errorIndex.
1864      */
1865     private int subParse(String text, int start, int patternCharIndex, int count,
1866                          boolean obeyCount, boolean[] ambiguousYear,
1867                          ParsePosition origPos,
1868                          boolean useFollowingMinusSignAsDelimiter, CalendarBuilder calb) {
1869         Number number;
1870         int value = 0;
1871         ParsePosition pos = new ParsePosition(0);
1872         pos.index = start;
1873         if (patternCharIndex == PATTERN_WEEK_YEAR && !calendar.isWeekDateSupported()) {
1874             // use calendar year 'y' instead
1875             patternCharIndex = PATTERN_YEAR;
1876         }
1877         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1878 
1879         // If there are any spaces here, skip over them.  If we hit the end
1880         // of the string, then fail.
1881         for (;;) {
1882             if (pos.index >= text.length()) {
1883                 origPos.errorIndex = start;
1884                 return -1;
1885             }
1886             char c = text.charAt(pos.index);
1887             if (c != ' ' && c != '\t') {
1888                 break;
1889             }
1890             ++pos.index;
1891         }
1892         // Remember the actual start index
1893         int actualStart = pos.index;
1894 
1895       parsing:
1896         {
1897             // We handle a few special cases here where we need to parse
1898             // a number value.  We handle further, more generic cases below.  We need
1899             // to handle some of them here because some fields require extra processing on
1900             // the parsed value.
1901             if (patternCharIndex == PATTERN_HOUR_OF_DAY1 ||
1902                 patternCharIndex == PATTERN_HOUR1 ||
1903                 (patternCharIndex == PATTERN_MONTH && count <= 2) ||
1904                 (patternCharIndex == PATTERN_MONTH_STANDALONE && count <= 2) ||
1905                 patternCharIndex == PATTERN_YEAR ||
1906                 patternCharIndex == PATTERN_WEEK_YEAR) {
1907                 // It would be good to unify this with the obeyCount logic below,
1908                 // but that's going to be difficult.
1909                 if (obeyCount) {
1910                     if ((start+count) > text.length()) {
1911                         break parsing;
1912                     }
1913                     number = numberFormat.parse(text.substring(0, start+count), pos);
1914                 } else {
1915                     number = numberFormat.parse(text, pos);
1916                 }
1917                 if (number == null) {
1918                     if (patternCharIndex != PATTERN_YEAR || calendar instanceof GregorianCalendar) {
1919                         break parsing;
1920                     }
1921                 } else {
1922                     value = number.intValue();
1923 
1924                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
1925                         (((pos.index < text.length()) &&
1926                          (text.charAt(pos.index) != minusSign)) ||
1927                          ((pos.index == text.length()) &&
1928                           (text.charAt(pos.index-1) == minusSign)))) {
1929                         value = -value;
1930                         pos.index--;
1931                     }
1932                 }
1933             }
1934 
1935             boolean useDateFormatSymbols = useDateFormatSymbols();
1936 
1937             int index;
1938             switch (patternCharIndex) {
1939             case PATTERN_ERA: // 'G'
1940                 if (useDateFormatSymbols) {
1941                     if ((index = matchString(text, start, Calendar.ERA, formatData.getEras(), calb)) > 0) {
1942                         return index;
1943                     }
1944                 } else {
1945                     Map<String, Integer> map = getDisplayNamesMap(field, locale);
1946                     if ((index = matchString(text, start, field, map, calb)) > 0) {
1947                         return index;
1948                     }
1949                 }
1950                 break parsing;
1951 
1952             case PATTERN_WEEK_YEAR: // 'Y'
1953             case PATTERN_YEAR:      // 'y'
1954                 if (!(calendar instanceof GregorianCalendar)) {
1955                     // calendar might have text representations for year values,
1956                     // such as "\u5143" in JapaneseImperialCalendar.
1957                     int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1958                     Map<String, Integer> map = calendar.getDisplayNames(field, style, locale);
1959                     if (map != null) {
1960                         if ((index = matchString(text, start, field, map, calb)) > 0) {
1961                             return index;
1962                         }
1963                     }
1964                     calb.set(field, value);
1965                     return pos.index;
1966                 }
1967 
1968                 // If there are 3 or more YEAR pattern characters, this indicates
1969                 // that the year value is to be treated literally, without any
1970                 // two-digit year adjustments (e.g., from "01" to 2001).  Otherwise
1971                 // we made adjustments to place the 2-digit year in the proper
1972                 // century, for parsed strings from "00" to "99".  Any other string
1973                 // is treated literally:  "2250", "-1", "1", "002".
1974                 if (count <= 2 && (pos.index - actualStart) == 2
1975                     && Character.isDigit(text.charAt(actualStart))
1976                     && Character.isDigit(text.charAt(actualStart + 1))) {
1977                     // Assume for example that the defaultCenturyStart is 6/18/1903.
1978                     // This means that two-digit years will be forced into the range
1979                     // 6/18/1903 to 6/17/2003.  As a result, years 00, 01, and 02
1980                     // correspond to 2000, 2001, and 2002.  Years 04, 05, etc. correspond
1981                     // to 1904, 1905, etc.  If the year is 03, then it is 2003 if the
1982                     // other fields specify a date before 6/18, or 1903 if they specify a
1983                     // date afterwards.  As a result, 03 is an ambiguous year.  All other
1984                     // two-digit years are unambiguous.
1985                     int ambiguousTwoDigitYear = defaultCenturyStartYear % 100;
1986                     ambiguousYear[0] = value == ambiguousTwoDigitYear;
1987                     value += (defaultCenturyStartYear/100)*100 +
1988                         (value < ambiguousTwoDigitYear ? 100 : 0);
1989                 }
1990                 calb.set(field, value);
1991                 return pos.index;
1992 
1993             case PATTERN_MONTH: // 'M'
1994                 if (count <= 2) // i.e., M or MM.
1995                 {
1996                     // Don't want to parse the month if it is a string
1997                     // while pattern uses numeric style: M or MM.
1998                     // [We computed 'value' above.]
1999                     calb.set(Calendar.MONTH, value - 1);
2000                     return pos.index;
2001                 }
2002 
2003                 if (useDateFormatSymbols) {
2004                     // count >= 3 // i.e., MMM or MMMM
2005                     // Want to be able to parse both short and long forms.
2006                     // Try count == 4 first:
2007                     int newStart;
2008                     if ((newStart = matchString(text, start, Calendar.MONTH,
2009                                                 formatData.getMonths(), calb)) > 0) {
2010                         return newStart;
2011                     }
2012                     // count == 4 failed, now try count == 3
2013                     if ((index = matchString(text, start, Calendar.MONTH,
2014                                              formatData.getShortMonths(), calb)) > 0) {
2015                         return index;
2016                     }
2017                 } else {
2018                     Map<String, Integer> map = getDisplayNamesMap(field, locale);
2019                     if ((index = matchString(text, start, field, map, calb)) > 0) {
2020                         return index;
2021                     }
2022                 }
2023                 break parsing;
2024 
2025             case PATTERN_MONTH_STANDALONE: // 'L'
2026                 if (count <= 2) {
2027                     // Don't want to parse the month if it is a string
2028                     // while pattern uses numeric style: L or LL
2029                     //[we computed 'value' above.]
2030                     calb.set(Calendar.MONTH, value - 1);
2031                     return pos.index;
2032                 }
2033                 Map<String, Integer> maps = getDisplayNamesMap(field, locale);
2034                 if ((index = matchString(text, start, field, maps, calb)) > 0) {
2035                     return index;
2036                 }
2037                 break parsing;
2038 
2039             case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
2040                 if (!isLenient()) {
2041                     // Validate the hour value in non-lenient
2042                     if (value < 1 || value > 24) {
2043                         break parsing;
2044                     }
2045                 }
2046                 // [We computed 'value' above.]
2047                 if (value == calendar.getMaximum(Calendar.HOUR_OF_DAY) + 1) {
2048                     value = 0;
2049                 }
2050                 calb.set(Calendar.HOUR_OF_DAY, value);
2051                 return pos.index;
2052 
2053             case PATTERN_DAY_OF_WEEK:  // 'E'
2054                 {
2055                     if (useDateFormatSymbols) {
2056                         // Want to be able to parse both short and long forms.
2057                         // Try count == 4 (DDDD) first:
2058                         int newStart;
2059                         if ((newStart=matchString(text, start, Calendar.DAY_OF_WEEK,
2060                                                   formatData.getWeekdays(), calb)) > 0) {
2061                             return newStart;
2062                         }
2063                         // DDDD failed, now try DDD
2064                         if ((index = matchString(text, start, Calendar.DAY_OF_WEEK,
2065                                                  formatData.getShortWeekdays(), calb)) > 0) {
2066                             return index;
2067                         }
2068                     } else {
2069                         int[] styles = { Calendar.LONG, Calendar.SHORT };
2070                         for (int style : styles) {
2071                             Map<String,Integer> map = calendar.getDisplayNames(field, style, locale);
2072                             if ((index = matchString(text, start, field, map, calb)) > 0) {
2073                                 return index;
2074                             }
2075                         }
2076                     }
2077                 }
2078                 break parsing;
2079 
2080             case PATTERN_AM_PM:    // 'a'
2081                 if (useDateFormatSymbols) {
2082                     if ((index = matchString(text, start, Calendar.AM_PM,
2083                                              formatData.getAmPmStrings(), calb)) > 0) {
2084                         return index;
2085                     }
2086                 } else {
2087                     Map<String,Integer> map = getDisplayNamesMap(field, locale);
2088                     if ((index = matchString(text, start, field, map, calb)) > 0) {
2089                         return index;
2090                     }
2091                 }
2092                 break parsing;
2093 
2094             case PATTERN_HOUR1: // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
2095                 if (!isLenient()) {
2096                     // Validate the hour value in non-lenient
2097                     if (value < 1 || value > 12) {
2098                         break parsing;
2099                     }
2100                 }
2101                 // [We computed 'value' above.]
2102                 if (value == calendar.getLeastMaximum(Calendar.HOUR) + 1) {
2103                     value = 0;
2104                 }
2105                 calb.set(Calendar.HOUR, value);
2106                 return pos.index;
2107 
2108             case PATTERN_ZONE_NAME:  // 'z'
2109             case PATTERN_ZONE_VALUE: // 'Z'
2110                 {
2111                     int sign = 0;
2112                     try {
2113                         char c = text.charAt(pos.index);
2114                         if (c == '+') {
2115                             sign = 1;
2116                         } else if (c == '-') {
2117                             sign = -1;
2118                         }
2119                         if (sign == 0) {
2120                             // Try parsing a custom time zone "GMT+hh:mm" or "GMT".
2121                             if ((c == 'G' || c == 'g')
2122                                 && (text.length() - start) >= GMT.length()
2123                                 && text.regionMatches(true, start, GMT, 0, GMT.length())) {
2124                                 pos.index = start + GMT.length();
2125 
2126                                 if ((text.length() - pos.index) > 0) {
2127                                     c = text.charAt(pos.index);
2128                                     if (c == '+') {
2129                                         sign = 1;
2130                                     } else if (c == '-') {
2131                                         sign = -1;
2132                                     }
2133                                 }
2134 
2135                                 if (sign == 0) {    /* "GMT" without offset */
2136                                     calb.set(Calendar.ZONE_OFFSET, 0)
2137                                         .set(Calendar.DST_OFFSET, 0);
2138                                     return pos.index;
2139                                 }
2140 
2141                                 // Parse the rest as "hh:mm"
2142                                 int i = subParseNumericZone(text, ++pos.index,
2143                                                             sign, 0, true, calb);
2144                                 if (i > 0) {
2145                                     return i;
2146                                 }
2147                                 pos.index = -i;
2148                             } else {
2149                                 // Try parsing the text as a time zone
2150                                 // name or abbreviation.
2151                                 int i = subParseZoneString(text, pos.index, calb);
2152                                 if (i > 0) {
2153                                     return i;
2154                                 }
2155                                 pos.index = -i;
2156                             }
2157                         } else {
2158                             // Parse the rest as "hhmm" (RFC 822)
2159                             int i = subParseNumericZone(text, ++pos.index,
2160                                                         sign, 0, false, calb);
2161                             if (i > 0) {
2162                                 return i;
2163                             }
2164                             pos.index = -i;
2165                         }
2166                     } catch (IndexOutOfBoundsException e) {
2167                     }
2168                 }
2169                 break parsing;
2170 
2171             case PATTERN_ISO_ZONE:   // 'X'
2172                 {
2173                     if ((text.length() - pos.index) <= 0) {
2174                         break parsing;
2175                     }
2176 
2177                     int sign;
2178                     char c = text.charAt(pos.index);
2179                     if (c == 'Z') {
2180                         calb.set(Calendar.ZONE_OFFSET, 0).set(Calendar.DST_OFFSET, 0);
2181                         return ++pos.index;
2182                     }
2183 
2184                     // parse text as "+/-hh[[:]mm]" based on count
2185                     if (c == '+') {
2186                         sign = 1;
2187                     } else if (c == '-') {
2188                         sign = -1;
2189                     } else {
2190                         ++pos.index;
2191                         break parsing;
2192                     }
2193                     int i = subParseNumericZone(text, ++pos.index, sign, count,
2194                                                 count == 3, calb);
2195                     if (i > 0) {
2196                         return i;
2197                     }
2198                     pos.index = -i;
2199                 }
2200                 break parsing;
2201 
2202             default:
2203          // case PATTERN_DAY_OF_MONTH:         // 'd'
2204          // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
2205          // case PATTERN_MINUTE:               // 'm'
2206          // case PATTERN_SECOND:               // 's'
2207          // case PATTERN_MILLISECOND:          // 'S'
2208          // case PATTERN_DAY_OF_YEAR:          // 'D'
2209          // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
2210          // case PATTERN_WEEK_OF_YEAR:         // 'w'
2211          // case PATTERN_WEEK_OF_MONTH:        // 'W'
2212          // case PATTERN_HOUR0:                // 'K' 0-based.  eg, 11PM + 1 hour =>> 0 AM
2213          // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' (pseudo field);
2214 
2215                 // Handle "generic" fields
2216                 if (obeyCount) {
2217                     if ((start+count) > text.length()) {
2218                         break parsing;
2219                     }
2220                     number = numberFormat.parse(text.substring(0, start+count), pos);
2221                 } else {
2222                     number = numberFormat.parse(text, pos);
2223                 }
2224                 if (number != null) {
2225                     value = number.intValue();
2226 
2227                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
2228                         (((pos.index < text.length()) &&
2229                          (text.charAt(pos.index) != minusSign)) ||
2230                          ((pos.index == text.length()) &&
2231                           (text.charAt(pos.index-1) == minusSign)))) {
2232                         value = -value;
2233                         pos.index--;
2234                     }
2235 
2236                     calb.set(field, value);
2237                     return pos.index;
2238                 }
2239                 break parsing;
2240             }
2241         }
2242 
2243         // Parsing failed.
2244         origPos.errorIndex = pos.index;
2245         return -1;
2246     }
2247 
2248     /**
2249      * Returns true if the DateFormatSymbols has been set explicitly or locale
2250      * is null.
2251      */
2252     private boolean useDateFormatSymbols() {
2253         return useDateFormatSymbols || locale == null;
2254     }
2255 
2256     /**
2257      * Translates a pattern, mapping each character in the from string to the
2258      * corresponding character in the to string.
2259      *
2260      * @exception IllegalArgumentException if the given pattern is invalid
2261      */
2262     private String translatePattern(String pattern, String from, String to) {
2263         StringBuilder result = new StringBuilder();
2264         boolean inQuote = false;
2265         for (int i = 0; i < pattern.length(); ++i) {
2266             char c = pattern.charAt(i);
2267             if (inQuote) {
2268                 if (c == '\'') {
2269                     inQuote = false;
2270                 }
2271             }
2272             else {
2273                 if (c == '\'') {
2274                     inQuote = true;
2275                 } else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
2276                     int ci = from.indexOf(c);
2277                     if (ci >= 0) {
2278                         // patternChars is longer than localPatternChars due
2279                         // to serialization compatibility. The pattern letters
2280                         // unsupported by localPatternChars pass through.
2281                         if (ci < to.length()) {
2282                             c = to.charAt(ci);
2283                         }
2284                     } else {
2285                         throw new IllegalArgumentException("Illegal pattern " +
2286                                                            " character '" +
2287                                                            c + "'");
2288                     }
2289                 }
2290             }
2291             result.append(c);
2292         }
2293         if (inQuote) {
2294             throw new IllegalArgumentException("Unfinished quote in pattern");
2295         }
2296         return result.toString();
2297     }
2298 
2299     /**
2300      * Returns a pattern string describing this date format.
2301      *
2302      * @return a pattern string describing this date format.
2303      */
2304     public String toPattern() {
2305         return pattern;
2306     }
2307 
2308     /**
2309      * Returns a localized pattern string describing this date format.
2310      *
2311      * @return a localized pattern string describing this date format.
2312      */
2313     public String toLocalizedPattern() {
2314         return translatePattern(pattern,
2315                                 DateFormatSymbols.patternChars,
2316                                 formatData.getLocalPatternChars());
2317     }
2318 
2319     /**
2320      * Applies the given pattern string to this date format.
2321      *
2322      * @param pattern the new date and time pattern for this date format
2323      * @exception NullPointerException if the given pattern is null
2324      * @exception IllegalArgumentException if the given pattern is invalid
2325      */
2326     public void applyPattern(String pattern)
2327     {
2328         applyPatternImpl(pattern);
2329     }
2330 
2331     private void applyPatternImpl(String pattern) {
2332         compiledPattern = compile(pattern);
2333         this.pattern = pattern;
2334     }
2335 
2336     /**
2337      * Applies the given localized pattern string to this date format.
2338      *
2339      * @param pattern a String to be mapped to the new date and time format
2340      *        pattern for this format
2341      * @exception NullPointerException if the given pattern is null
2342      * @exception IllegalArgumentException if the given pattern is invalid
2343      */
2344     public void applyLocalizedPattern(String pattern) {
2345          String p = translatePattern(pattern,
2346                                      formatData.getLocalPatternChars(),
2347                                      DateFormatSymbols.patternChars);
2348          compiledPattern = compile(p);
2349          this.pattern = p;
2350     }
2351 
2352     /**
2353      * Gets a copy of the date and time format symbols of this date format.
2354      *
2355      * @return the date and time format symbols of this date format
2356      * @see #setDateFormatSymbols
2357      */
2358     public DateFormatSymbols getDateFormatSymbols()
2359     {
2360         return (DateFormatSymbols)formatData.clone();
2361     }
2362 
2363     /**
2364      * Sets the date and time format symbols of this date format.
2365      *
2366      * @param newFormatSymbols the new date and time format symbols
2367      * @exception NullPointerException if the given newFormatSymbols is null
2368      * @see #getDateFormatSymbols
2369      */
2370     public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
2371     {
2372         this.formatData = (DateFormatSymbols)newFormatSymbols.clone();
2373         useDateFormatSymbols = true;
2374     }
2375 
2376     /**
2377      * Creates a copy of this <code>SimpleDateFormat</code>. This also
2378      * clones the format's date format symbols.
2379      *
2380      * @return a clone of this <code>SimpleDateFormat</code>
2381      */
2382     @Override
2383     public Object clone() {
2384         SimpleDateFormat other = (SimpleDateFormat) super.clone();
2385         other.formatData = (DateFormatSymbols) formatData.clone();
2386         return other;
2387     }
2388 
2389     /**
2390      * Returns the hash code value for this <code>SimpleDateFormat</code> object.
2391      *
2392      * @return the hash code value for this <code>SimpleDateFormat</code> object.
2393      */
2394     @Override
2395     public int hashCode()
2396     {
2397         return pattern.hashCode();
2398         // just enough fields for a reasonable distribution
2399     }
2400 
2401     /**
2402      * Compares the given object with this <code>SimpleDateFormat</code> for
2403      * equality.
2404      *
2405      * @return true if the given object is equal to this
2406      * <code>SimpleDateFormat</code>
2407      */
2408     @Override
2409     public boolean equals(Object obj)
2410     {
2411         if (!super.equals(obj)) {
2412             return false; // super does class check
2413         }
2414         SimpleDateFormat that = (SimpleDateFormat) obj;
2415         return (pattern.equals(that.pattern)
2416                 && formatData.equals(that.formatData));
2417     }
2418 
2419     private static final int[] REST_OF_STYLES = {
2420         Calendar.SHORT_STANDALONE, Calendar.LONG_FORMAT, Calendar.LONG_STANDALONE,
2421     };
2422     private Map<String, Integer> getDisplayNamesMap(int field, Locale locale) {
2423         Map<String, Integer> map = calendar.getDisplayNames(field, Calendar.SHORT_FORMAT, locale);
2424         // Get all SHORT and LONG styles (avoid NARROW styles).
2425         for (int style : REST_OF_STYLES) {
2426             Map<String, Integer> m = calendar.getDisplayNames(field, style, locale);
2427             if (m != null) {
2428                 map.putAll(m);
2429             }
2430         }
2431         return map;
2432     }
2433 
2434     /**
2435      * After reading an object from the input stream, the format
2436      * pattern in the object is verified.
2437      *
2438      * @exception InvalidObjectException if the pattern is invalid
2439      */
2440     private void readObject(ObjectInputStream stream)
2441                          throws IOException, ClassNotFoundException {
2442         stream.defaultReadObject();
2443 
2444         try {
2445             compiledPattern = compile(pattern);
2446         } catch (Exception e) {
2447             throw new InvalidObjectException("invalid pattern");
2448         }
2449 
2450         if (serialVersionOnStream < 1) {
2451             // didn't have defaultCenturyStart field
2452             initializeDefaultCentury();
2453         }
2454         else {
2455             // fill in dependent transient field
2456             parseAmbiguousDatesAsAfter(defaultCenturyStart);
2457         }
2458         serialVersionOnStream = currentSerialVersion;
2459 
2460         // If the deserialized object has a SimpleTimeZone, try
2461         // to replace it with a ZoneInfo equivalent in order to
2462         // be compatible with the SimpleTimeZone-based
2463         // implementation as much as possible.
2464         TimeZone tz = getTimeZone();
2465         if (tz instanceof SimpleTimeZone) {
2466             String id = tz.getID();
2467             TimeZone zi = TimeZone.getTimeZone(id);
2468             if (zi != null && zi.hasSameRules(tz) && zi.getID().equals(id)) {
2469                 setTimeZone(zi);
2470             }
2471         }
2472     }
2473 
2474     /**
2475      * Analyze the negative subpattern of DecimalFormat and set/update values
2476      * as necessary.
2477      */
2478     private void checkNegativeNumberExpression() {
2479         if ((numberFormat instanceof DecimalFormat) &&
2480             !numberFormat.equals(originalNumberFormat)) {
2481             String numberPattern = ((DecimalFormat)numberFormat).toPattern();
2482             if (!numberPattern.equals(originalNumberPattern)) {
2483                 hasFollowingMinusSign = false;
2484 
2485                 int separatorIndex = numberPattern.indexOf(';');
2486                 // If the negative subpattern is not absent, we have to analayze
2487                 // it in order to check if it has a following minus sign.
2488                 if (separatorIndex > -1) {
2489                     int minusIndex = numberPattern.indexOf('-', separatorIndex);
2490                     if ((minusIndex > numberPattern.lastIndexOf('0')) &&
2491                         (minusIndex > numberPattern.lastIndexOf('#'))) {
2492                         hasFollowingMinusSign = true;
2493                         minusSign = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getMinusSign();
2494                     }
2495                 }
2496                 originalNumberPattern = numberPattern;
2497             }
2498             originalNumberFormat = numberFormat;
2499         }
2500     }
2501 
2502 }