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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
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8    * particular file as subject to the "Classpath" exception as provided
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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   *
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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 java.util.Calendar;
45  import java.util.Date;
46  import java.util.GregorianCalendar;
47  import java.util.Locale;
48  import java.util.Map;
49  import java.util.MissingResourceException;
50  import java.util.ResourceBundle;
51  import java.util.SimpleTimeZone;
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.resources.LocaleData;
58  
59  import static java.text.DateFormatSymbols.*;
60  
61  /**
62   * <code>SimpleDateFormat</code> is a concrete class for formatting and
63   * parsing dates in a locale-sensitive manner. It allows for formatting
64   * (date -> text), parsing (text -> date), and normalization.
65   *
66   * <p>
67   * <code>SimpleDateFormat</code> allows you to start by choosing
68   * any user-defined patterns for date-time formatting. However, you
69   * are encouraged to create a date-time formatter with either
70   * <code>getTimeInstance</code>, <code>getDateInstance</code>, or
71   * <code>getDateTimeInstance</code> in <code>DateFormat</code>. Each
72   * of these class methods can return a date/time formatter initialized
73   * with a default format pattern. You may modify the format pattern
74   * using the <code>applyPattern</code> methods as desired.
75   * For more information on using these methods, see
76   * {@link DateFormat}.
77   *
78   * <h4>Date and Time Patterns</h4>
79   * <p>
80   * Date and time formats are specified by <em>date and time pattern</em>
81   * strings.
82   * Within date and time pattern strings, unquoted letters from
83   * <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to
84   * <code>'z'</code> are interpreted as pattern letters representing the
85   * components of a date or time string.
86   * Text can be quoted using single quotes (<code>'</code>) to avoid
87   * interpretation.
88   * <code>"''"</code> represents a single quote.
89   * All other characters are not interpreted; they're simply copied into the
90   * output string during formatting or matched against the input string
91   * during parsing.
92   * <p>
93   * The following pattern letters are defined (all other characters from
94   * <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to
95   * <code>'z'</code> are reserved):
96   * <blockquote>
97   * <table border=0 cellspacing=3 cellpadding=0 summary="Chart shows pattern letters, date/time component, presentation, and examples.">
98   *     <tr bgcolor="#ccccff">
99   *         <th align=left>Letter
100  *         <th align=left>Date or Time Component
101  *         <th align=left>Presentation
102  *         <th align=left>Examples
103  *     <tr>
104  *         <td><code>G</code>
105  *         <td>Era designator
106  *         <td><a href="#text">Text</a>
107  *         <td><code>AD</code>
108  *     <tr bgcolor="#eeeeff">
109  *         <td><code>y</code>
110  *         <td>Year
111  *         <td><a href="#year">Year</a>
112  *         <td><code>1996</code>; <code>96</code>
113  *     <tr>
114  *         <td><code>Y</code>
115  *         <td>Week year
116  *         <td><a href="#year">Year</a>
117  *         <td><code>2009</code>; <code>09</code>
118  *     <tr bgcolor="#eeeeff">
119  *         <td><code>M</code>
120  *         <td>Month in year
121  *         <td><a href="#month">Month</a>
122  *         <td><code>July</code>; <code>Jul</code>; <code>07</code>
123  *     <tr>
124  *         <td><code>w</code>
125  *         <td>Week in year
126  *         <td><a href="#number">Number</a>
127  *         <td><code>27</code>
128  *     <tr bgcolor="#eeeeff">
129  *         <td><code>W</code>
130  *         <td>Week in month
131  *         <td><a href="#number">Number</a>
132  *         <td><code>2</code>
133  *     <tr>
134  *         <td><code>D</code>
135  *         <td>Day in year
136  *         <td><a href="#number">Number</a>
137  *         <td><code>189</code>
138  *     <tr bgcolor="#eeeeff">
139  *         <td><code>d</code>
140  *         <td>Day in month
141  *         <td><a href="#number">Number</a>
142  *         <td><code>10</code>
143  *     <tr>
144  *         <td><code>F</code>
145  *         <td>Day of week in month
146  *         <td><a href="#number">Number</a>
147  *         <td><code>2</code>
148  *     <tr bgcolor="#eeeeff">
149  *         <td><code>E</code>
150  *         <td>Day name in week
151  *         <td><a href="#text">Text</a>
152  *         <td><code>Tuesday</code>; <code>Tue</code>
153  *     <tr>
154  *         <td><code>u</code>
155  *         <td>Day number of week (1 = Monday, ..., 7 = Sunday)
156  *         <td><a href="#number">Number</a>
157  *         <td><code>1</code>
158  *     <tr bgcolor="#eeeeff">
159  *         <td><code>a</code>
160  *         <td>Am/pm marker
161  *         <td><a href="#text">Text</a>
162  *         <td><code>PM</code>
163  *     <tr>
164  *         <td><code>H</code>
165  *         <td>Hour in day (0-23)
166  *         <td><a href="#number">Number</a>
167  *         <td><code>0</code>
168  *     <tr bgcolor="#eeeeff">
169  *         <td><code>k</code>
170  *         <td>Hour in day (1-24)
171  *         <td><a href="#number">Number</a>
172  *         <td><code>24</code>
173  *     <tr>
174  *         <td><code>K</code>
175  *         <td>Hour in am/pm (0-11)
176  *         <td><a href="#number">Number</a>
177  *         <td><code>0</code>
178  *     <tr bgcolor="#eeeeff">
179  *         <td><code>h</code>
180  *         <td>Hour in am/pm (1-12)
181  *         <td><a href="#number">Number</a>
182  *         <td><code>12</code>
183  *     <tr>
184  *         <td><code>m</code>
185  *         <td>Minute in hour
186  *         <td><a href="#number">Number</a>
187  *         <td><code>30</code>
188  *     <tr bgcolor="#eeeeff">
189  *         <td><code>s</code>
190  *         <td>Second in minute
191  *         <td><a href="#number">Number</a>
192  *         <td><code>55</code>
193  *     <tr>
194  *         <td><code>S</code>
195  *         <td>Millisecond
196  *         <td><a href="#number">Number</a>
197  *         <td><code>978</code>
198  *     <tr bgcolor="#eeeeff">
199  *         <td><code>z</code>
200  *         <td>Time zone
201  *         <td><a href="#timezone">General time zone</a>
202  *         <td><code>Pacific Standard Time</code>; <code>PST</code>; <code>GMT-08:00</code>
203  *     <tr>
204  *         <td><code>Z</code>
205  *         <td>Time zone
206  *         <td><a href="#rfc822timezone">RFC 822 time zone</a>
207  *         <td><code>-0800</code>
208  *     <tr bgcolor="#eeeeff">
209  *         <td><code>X</code>
210  *         <td>Time zone
211  *         <td><a href="#iso8601timezone">ISO 8601 time zone</a>
212  *         <td><code>-08</code>; <code>-0800</code>;  <code>-08:00</code>
213  * </table>
214  * </blockquote>
215  * Pattern letters are usually repeated, as their number determines the
216  * exact presentation:
217  * <ul>
218  * <li><strong><a name="text">Text:</a></strong>
219  *     For formatting, if the number of pattern letters is 4 or more,
220  *     the full form is used; otherwise a short or abbreviated form
221  *     is used if available.
222  *     For parsing, both forms are accepted, independent of the number
223  *     of pattern letters.<br><br></li>
224  * <li><strong><a name="number">Number:</a></strong>
225  *     For formatting, the number of pattern letters is the minimum
226  *     number of digits, and shorter numbers are zero-padded to this amount.
227  *     For parsing, the number of pattern letters is ignored unless
228  *     it's needed to separate two adjacent fields.<br><br></li>
229  * <li><strong><a name="year">Year:</a></strong>
230  *     If the formatter's {@link #getCalendar() Calendar} is the Gregorian
231  *     calendar, the following rules are applied.<br>
232  *     <ul>
233  *     <li>For formatting, if the number of pattern letters is 2, the year
234  *         is truncated to 2 digits; otherwise it is interpreted as a
235  *         <a href="#number">number</a>.
236  *     <li>For parsing, if the number of pattern letters is more than 2,
237  *         the year is interpreted literally, regardless of the number of
238  *         digits. So using the pattern "MM/dd/yyyy", "01/11/12" parses to
239  *         Jan 11, 12 A.D.
240  *     <li>For parsing with the abbreviated year pattern ("y" or "yy"),
241  *         <code>SimpleDateFormat</code> must interpret the abbreviated year
242  *         relative to some century.  It does this by adjusting dates to be
243  *         within 80 years before and 20 years after the time the <code>SimpleDateFormat</code>
244  *         instance is created. For example, using a pattern of "MM/dd/yy" and a
245  *         <code>SimpleDateFormat</code> instance created on Jan 1, 1997,  the string
246  *         "01/11/12" would be interpreted as Jan 11, 2012 while the string "05/04/64"
247  *         would be interpreted as May 4, 1964.
248  *         During parsing, only strings consisting of exactly two digits, as defined by
249  *         {@link Character#isDigit(char)}, will be parsed into the default century.
250  *         Any other numeric string, such as a one digit string, a three or more digit
251  *         string, or a two digit string that isn't all digits (for example, "-1"), is
252  *         interpreted literally.  So "01/02/3" or "01/02/003" are parsed, using the
253  *         same pattern, as Jan 2, 3 AD.  Likewise, "01/02/-3" is parsed as Jan 2, 4 BC.
254  *     </ul>
255  *     Otherwise, calendar system specific forms are applied.
256  *     For both formatting and parsing, if the number of pattern
257  *     letters is 4 or more, a calendar specific {@linkplain
258  *     Calendar#LONG long form} is used. Otherwise, a calendar
259  *     specific {@linkplain Calendar#SHORT short or abbreviated form}
260  *     is used.<br>
261  *     <br>
262  *     If week year {@code 'Y'} is specified and the {@linkplain
263  *     #getCalendar() calendar} doesn't support any <a
264  *     href="../util/GregorianCalendar.html#week_year"> week
265  *     years</a>, the calendar year ({@code 'y'}) is used instead. The
266  *     support of week years can be tested with a call to {@link
267  *     DateFormat#getCalendar() getCalendar()}.{@link
268  *     java.util.Calendar#isWeekDateSupported()
269  *     isWeekDateSupported()}.<br><br></li>
270  * <li><strong><a name="month">Month:</a></strong>
271  *     If the number of pattern letters is 3 or more, the month is
272  *     interpreted as <a href="#text">text</a>; otherwise,
273  *     it is interpreted as a <a href="#number">number</a>.<br><br></li>
274  * <li><strong><a name="timezone">General time zone:</a></strong>
275  *     Time zones are interpreted as <a href="#text">text</a> if they have
276  *     names. For time zones representing a GMT offset value, the
277  *     following syntax is used:
278  *     <pre>
279  *     <a name="GMTOffsetTimeZone"><i>GMTOffsetTimeZone:</i></a>
280  *             <code>GMT</code> <i>Sign</i> <i>Hours</i> <code>:</code> <i>Minutes</i>
281  *     <i>Sign:</i> one of
282  *             <code>+ -</code>
283  *     <i>Hours:</i>
284  *             <i>Digit</i>
285  *             <i>Digit</i> <i>Digit</i>
286  *     <i>Minutes:</i>
287  *             <i>Digit</i> <i>Digit</i>
288  *     <i>Digit:</i> one of
289  *             <code>0 1 2 3 4 5 6 7 8 9</code></pre>
290  *     <i>Hours</i> must be between 0 and 23, and <i>Minutes</i> must be between
291  *     00 and 59. The format is locale independent and digits must be taken
292  *     from the Basic Latin block of the Unicode standard.
293  *     <p>For parsing, <a href="#rfc822timezone">RFC 822 time zones</a> are also
294  *     accepted.<br><br></li>
295  * <li><strong><a name="rfc822timezone">RFC 822 time zone:</a></strong>
296  *     For formatting, the RFC 822 4-digit time zone format is used:
297  *
298  *     <pre>
299  *     <i>RFC822TimeZone:</i>
300  *             <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
301  *     <i>TwoDigitHours:</i>
302  *             <i>Digit Digit</i></pre>
303  *     <i>TwoDigitHours</i> must be between 00 and 23. Other definitions
304  *     are as for <a href="#timezone">general time zones</a>.
305  *
306  *     <p>For parsing, <a href="#timezone">general time zones</a> are also
307  *     accepted.
308  * <li><strong><a name="iso8601timezone">ISO 8601 Time zone:</a></strong>
309  *     The number of pattern letters designates the format for both formatting
310  *     and parsing as follows:
311  *     <pre>
312  *     <i>ISO8601TimeZone:</i>
313  *             <i>OneLetterISO8601TimeZone</i>
314  *             <i>TwoLetterISO8601TimeZone</i>
315  *             <i>ThreeLetterISO8601TimeZone</i>
316  *     <i>OneLetterISO8601TimeZone:</i>
317  *             <i>Sign</i> <i>TwoDigitHours</i>
318  *             {@code Z}
319  *     <i>TwoLetterISO8601TimeZone:</i>
320  *             <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>
321  *             {@code Z}
322  *     <i>ThreeLetterISO8601TimeZone:</i>
323  *             <i>Sign</i> <i>TwoDigitHours</i> {@code :} <i>Minutes</i>
324  *             {@code Z}</pre>
325  *     Other definitions are as for <a href="#timezone">general time zones</a> or
326  *     <a href="#rfc822timezone">RFC 822 time zones</a>.
327  *
328  *     <p>For formatting, if the offset value from GMT is 0, {@code "Z"} is
329  *     produced. If the number of pattern letters is 1, any fraction of an hour
330  *     is ignored. For example, if the pattern is {@code "X"} and the time zone is
331  *     {@code "GMT+05:30"}, {@code "+05"} is produced.
332  *
333  *     <p>For parsing, {@code "Z"} is parsed as the UTC time zone designator.
334  *     <a href="#timezone">General time zones</a> are <em>not</em> accepted.
335  *
336  *     <p>If the number of pattern letters is 4 or more, {@link
337  *     IllegalArgumentException} is thrown when constructing a {@code
338  *     SimpleDateFormat} or {@linkplain #applyPattern(String) applying a
339  *     pattern}.
340  * </ul>
341  * <code>SimpleDateFormat</code> also supports <em>localized date and time
342  * pattern</em> strings. In these strings, the pattern letters described above
343  * may be replaced with other, locale dependent, pattern letters.
344  * <code>SimpleDateFormat</code> does not deal with the localization of text
345  * other than the pattern letters; that's up to the client of the class.
346  * <p>
347  *
348  * <h4>Examples</h4>
349  *
350  * The following examples show how date and time patterns are interpreted in
351  * the U.S. locale. The given date and time are 2001-07-04 12:08:56 local time
352  * in the U.S. Pacific Time time zone.
353  * <blockquote>
354  * <table border=0 cellspacing=3 cellpadding=0 summary="Examples of date and time patterns interpreted in the U.S. locale">
355  *     <tr bgcolor="#ccccff">
356  *         <th align=left>Date and Time Pattern
357  *         <th align=left>Result
358  *     <tr>
359  *         <td><code>"yyyy.MM.dd G 'at' HH:mm:ss z"</code>
360  *         <td><code>2001.07.04 AD at 12:08:56 PDT</code>
361  *     <tr bgcolor="#eeeeff">
362  *         <td><code>"EEE, MMM d, ''yy"</code>
363  *         <td><code>Wed, Jul 4, '01</code>
364  *     <tr>
365  *         <td><code>"h:mm a"</code>
366  *         <td><code>12:08 PM</code>
367  *     <tr bgcolor="#eeeeff">
368  *         <td><code>"hh 'o''clock' a, zzzz"</code>
369  *         <td><code>12 o'clock PM, Pacific Daylight Time</code>
370  *     <tr>
371  *         <td><code>"K:mm a, z"</code>
372  *         <td><code>0:08 PM, PDT</code>
373  *     <tr bgcolor="#eeeeff">
374  *         <td><code>"yyyyy.MMMMM.dd GGG hh:mm aaa"</code>
375  *         <td><code>02001.July.04 AD 12:08 PM</code>
376  *     <tr>
377  *         <td><code>"EEE, d MMM yyyy HH:mm:ss Z"</code>
378  *         <td><code>Wed, 4 Jul 2001 12:08:56 -0700</code>
379  *     <tr bgcolor="#eeeeff">
380  *         <td><code>"yyMMddHHmmssZ"</code>
381  *         <td><code>010704120856-0700</code>
382  *     <tr>
383  *         <td><code>"yyyy-MM-dd'T'HH:mm:ss.SSSZ"</code>
384  *         <td><code>2001-07-04T12:08:56.235-0700</code>
385  *     <tr bgcolor="#eeeeff">
386  *         <td><code>"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"</code>
387  *         <td><code>2001-07-04T12:08:56.235-07:00</code>
388  *     <tr>
389  *         <td><code>"YYYY-'W'ww-u"</code>
390  *         <td><code>2001-W27-3</code>
391  * </table>
392  * </blockquote>
393  *
394  * <h4><a name="synchronization">Synchronization</a></h4>
395  *
396  * <p>
397  * Date formats are not synchronized.
398  * It is recommended to create separate format instances for each thread.
399  * If multiple threads access a format concurrently, it must be synchronized
400  * externally.
401  *
402  * @see          <a href="http://java.sun.com/docs/books/tutorial/i18n/format/simpleDateFormat.html">Java Tutorial</a>
403  * @see          java.util.Calendar
404  * @see          java.util.TimeZone
405  * @see          DateFormat
406  * @see          DateFormatSymbols
407  * @author       Mark Davis, Chen-Lieh Huang, Alan Liu
408  */
409 public class SimpleDateFormat extends DateFormat {
410 
411     // the official serial version ID which says cryptically
412     // which version we're compatible with
413     static final long serialVersionUID = 4774881970558875024L;
414 
415     // the internal serial version which says which version was written
416     // - 0 (default) for version up to JDK 1.1.3
417     // - 1 for version from JDK 1.1.4, which includes a new field
418     static final int currentSerialVersion = 1;
419 
420     /**
421      * The version of the serialized data on the stream.  Possible values:
422      * <ul>
423      * <li><b>0</b> or not present on stream: JDK 1.1.3.  This version
424      * has no <code>defaultCenturyStart</code> on stream.
425      * <li><b>1</b> JDK 1.1.4 or later.  This version adds
426      * <code>defaultCenturyStart</code>.
427      * </ul>
428      * When streaming out this class, the most recent format
429      * and the highest allowable <code>serialVersionOnStream</code>
430      * is written.
431      * @serial
432      * @since JDK1.1.4
433      */
434     private int serialVersionOnStream = currentSerialVersion;
435 
436     /**
437      * The pattern string of this formatter.  This is always a non-localized
438      * pattern.  May not be null.  See class documentation for details.
439      * @serial
440      */
441     private String pattern;
442 
443     /**
444      * Saved numberFormat and pattern.
445      * @see SimpleDateFormat#checkNegativeNumberExpression
446      */
447     transient private NumberFormat originalNumberFormat;
448     transient private String originalNumberPattern;
449 
450     /**
451      * The minus sign to be used with format and parse.
452      */
453     transient private char minusSign = '-';
454 
455     /**
456      * True when a negative sign follows a number.
457      * (True as default in Arabic.)
458      */
459     transient private boolean hasFollowingMinusSign = false;
460 
461     /**
462      * The compiled pattern.
463      */
464     transient private char[] compiledPattern;
465 
466     /**
467      * Tags for the compiled pattern.
468      */
469     private final static int TAG_QUOTE_ASCII_CHAR       = 100;
470     private final static int TAG_QUOTE_CHARS            = 101;
471 
472     /**
473      * Locale dependent digit zero.
474      * @see #zeroPaddingNumber
475      * @see java.text.DecimalFormatSymbols#getZeroDigit
476      */
477     transient private char zeroDigit;
478 
479     /**
480      * The symbols used by this formatter for week names, month names,
481      * etc.  May not be null.
482      * @serial
483      * @see java.text.DateFormatSymbols
484      */
485     private DateFormatSymbols formatData;
486 
487     /**
488      * We map dates with two-digit years into the century starting at
489      * <code>defaultCenturyStart</code>, which may be any date.  May
490      * not be null.
491      * @serial
492      * @since JDK1.1.4
493      */
494     private Date defaultCenturyStart;
495 
496     transient private int defaultCenturyStartYear;
497 
498     private static final int MILLIS_PER_MINUTE = 60 * 1000;
499 
500     // For time zones that have no names, use strings GMT+minutes and
501     // GMT-minutes. For instance, in France the time zone is GMT+60.
502     private static final String GMT = "GMT";
503 
504     /**
505      * Cache to hold the DateTimePatterns of a Locale.
506      */
507     private static final ConcurrentMap<Locale, String[]> cachedLocaleData
508         = new ConcurrentHashMap<Locale, String[]>(3);
509 
510     /**
511      * Cache NumberFormat instances with Locale key.
512      */
513     private static final ConcurrentMap<Locale, NumberFormat> cachedNumberFormatData
514         = new ConcurrentHashMap<Locale, NumberFormat>(3);
515 
516     /**
517      * The Locale used to instantiate this
518      * <code>SimpleDateFormat</code>. The value may be null if this object
519      * has been created by an older <code>SimpleDateFormat</code> and
520      * deserialized.
521      *
522      * @serial
523      * @since 1.6
524      */
525     private Locale locale;
526 
527     /**
528      * Indicates whether this <code>SimpleDateFormat</code> should use
529      * the DateFormatSymbols. If true, the format and parse methods
530      * use the DateFormatSymbols values. If false, the format and
531      * parse methods call Calendar.getDisplayName or
532      * Calendar.getDisplayNames.
533      */
534     transient boolean useDateFormatSymbols;
535 
536     /**
537      * Constructs a <code>SimpleDateFormat</code> using the default pattern and
538      * date format symbols for the default locale.
539      * <b>Note:</b> This constructor may not support all locales.
540      * For full coverage, use the factory methods in the {@link DateFormat}
541      * class.
542      */
543     public SimpleDateFormat() {
544         this(SHORT, SHORT, Locale.getDefault(Locale.Category.FORMAT));
545     }
546 
547     /**
548      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
549      * the default date format symbols for the default locale.
550      * <b>Note:</b> This constructor may not support all locales.
551      * For full coverage, use the factory methods in the {@link DateFormat}
552      * class.
553      *
554      * @param pattern the pattern describing the date and time format
555      * @exception NullPointerException if the given pattern is null
556      * @exception IllegalArgumentException if the given pattern is invalid
557      */
558     public SimpleDateFormat(String pattern)
559     {
560         this(pattern, Locale.getDefault(Locale.Category.FORMAT));
561     }
562 
563     /**
564      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
565      * the default date format symbols for the given locale.
566      * <b>Note:</b> This constructor may not support all locales.
567      * For full coverage, use the factory methods in the {@link DateFormat}
568      * class.
569      *
570      * @param pattern the pattern describing the date and time format
571      * @param locale the locale whose date format symbols should be used
572      * @exception NullPointerException if the given pattern or locale is null
573      * @exception IllegalArgumentException if the given pattern is invalid
574      */
575     public SimpleDateFormat(String pattern, Locale locale)
576     {
577         if (pattern == null || locale == null) {
578             throw new NullPointerException();
579         }
580 
581         initializeCalendar(locale);
582         this.pattern = pattern;
583         this.formatData = DateFormatSymbols.getInstanceRef(locale);
584         this.locale = locale;
585         initialize(locale);
586     }
587 
588     /**
589      * Constructs a <code>SimpleDateFormat</code> using the given pattern and
590      * date format symbols.
591      *
592      * @param pattern the pattern describing the date and time format
593      * @param formatSymbols the date format symbols to be used for formatting
594      * @exception NullPointerException if the given pattern or formatSymbols is null
595      * @exception IllegalArgumentException if the given pattern is invalid
596      */
597     public SimpleDateFormat(String pattern, DateFormatSymbols formatSymbols)
598     {
599         if (pattern == null || formatSymbols == null) {
600             throw new NullPointerException();
601         }
602 
603         this.pattern = pattern;
604         this.formatData = (DateFormatSymbols) formatSymbols.clone();
605         this.locale = Locale.getDefault(Locale.Category.FORMAT);
606         initializeCalendar(this.locale);
607         initialize(this.locale);
608         useDateFormatSymbols = true;
609     }
610 
611     /* Package-private, called by DateFormat factory methods */
612     SimpleDateFormat(int timeStyle, int dateStyle, Locale loc) {
613         if (loc == null) {
614             throw new NullPointerException();
615         }
616 
617         this.locale = loc;
618         // initialize calendar and related fields
619         initializeCalendar(loc);
620 
621         /* try the cache first */
622         String[] dateTimePatterns = cachedLocaleData.get(loc);
623         if (dateTimePatterns == null) { /* cache miss */
624             ResourceBundle r = LocaleData.getDateFormatData(loc);
625             if (!isGregorianCalendar()) {
626                 try {
627                     dateTimePatterns = r.getStringArray(getCalendarName() + ".DateTimePatterns");
628                 } catch (MissingResourceException e) {
629                 }
630             }
631             if (dateTimePatterns == null) {
632                 dateTimePatterns = r.getStringArray("DateTimePatterns");
633             }
634             /* update cache */
635             cachedLocaleData.putIfAbsent(loc, dateTimePatterns);
636         }
637         formatData = DateFormatSymbols.getInstanceRef(loc);
638         if ((timeStyle >= 0) && (dateStyle >= 0)) {
639             Object[] dateTimeArgs = {dateTimePatterns[timeStyle],
640                                      dateTimePatterns[dateStyle + 4]};
641             pattern = MessageFormat.format(dateTimePatterns[8], dateTimeArgs);
642         }
643         else if (timeStyle >= 0) {
644             pattern = dateTimePatterns[timeStyle];
645         }
646         else if (dateStyle >= 0) {
647             pattern = dateTimePatterns[dateStyle + 4];
648         }
649         else {
650             throw new IllegalArgumentException("No date or time style specified");
651         }
652 
653         initialize(loc);
654     }
655 
656     /* Initialize compiledPattern and numberFormat fields */
657     private void initialize(Locale loc) {
658         // Verify and compile the given pattern.
659         compiledPattern = compile(pattern);
660 
661         /* try the cache first */
662         numberFormat = cachedNumberFormatData.get(loc);
663         if (numberFormat == null) { /* cache miss */
664             numberFormat = NumberFormat.getIntegerInstance(loc);
665             numberFormat.setGroupingUsed(false);
666 
667             /* update cache */
668             cachedNumberFormatData.putIfAbsent(loc, numberFormat);
669         }
670         numberFormat = (NumberFormat) numberFormat.clone();
671 
672         initializeDefaultCentury();
673     }
674 
675     private void initializeCalendar(Locale loc) {
676         if (calendar == null) {
677             assert loc != null;
678             // The format object must be constructed using the symbols for this zone.
679             // However, the calendar should use the current default TimeZone.
680             // If this is not contained in the locale zone strings, then the zone
681             // will be formatted using generic GMT+/-H:MM nomenclature.
682             calendar = Calendar.getInstance(TimeZone.getDefault(), loc);
683         }
684     }
685 
686     /**
687      * Returns the compiled form of the given pattern. The syntax of
688      * the compiled pattern is:
689      * <blockquote>
690      * CompiledPattern:
691      *     EntryList
692      * EntryList:
693      *     Entry
694      *     EntryList Entry
695      * Entry:
696      *     TagField
697      *     TagField data
698      * TagField:
699      *     Tag Length
700      *     TaggedData
701      * Tag:
702      *     pattern_char_index
703      *     TAG_QUOTE_CHARS
704      * Length:
705      *     short_length
706      *     long_length
707      * TaggedData:
708      *     TAG_QUOTE_ASCII_CHAR ascii_char
709      *
710      * </blockquote>
711      *
712      * where `short_length' is an 8-bit unsigned integer between 0 and
713      * 254.  `long_length' is a sequence of an 8-bit integer 255 and a
714      * 32-bit signed integer value which is split into upper and lower
715      * 16-bit fields in two char's. `pattern_char_index' is an 8-bit
716      * integer between 0 and 18. `ascii_char' is an 7-bit ASCII
717      * character value. `data' depends on its Tag value.
718      * <p>
719      * If Length is short_length, Tag and short_length are packed in a
720      * single char, as illustrated below.
721      * <blockquote>
722      *     char[0] = (Tag << 8) | short_length;
723      * </blockquote>
724      *
725      * If Length is long_length, Tag and 255 are packed in the first
726      * char and a 32-bit integer, as illustrated below.
727      * <blockquote>
728      *     char[0] = (Tag << 8) | 255;
729      *     char[1] = (char) (long_length >>> 16);
730      *     char[2] = (char) (long_length & 0xffff);
731      * </blockquote>
732      * <p>
733      * If Tag is a pattern_char_index, its Length is the number of
734      * pattern characters. For example, if the given pattern is
735      * "yyyy", Tag is 1 and Length is 4, followed by no data.
736      * <p>
737      * If Tag is TAG_QUOTE_CHARS, its Length is the number of char's
738      * following the TagField. For example, if the given pattern is
739      * "'o''clock'", Length is 7 followed by a char sequence of
740      * <code>o&nbs;'&nbs;c&nbs;l&nbs;o&nbs;c&nbs;k</code>.
741      * <p>
742      * TAG_QUOTE_ASCII_CHAR is a special tag and has an ASCII
743      * character in place of Length. For example, if the given pattern
744      * is "'o'", the TaggedData entry is
745      * <code>((TAG_QUOTE_ASCII_CHAR&nbs;<<&nbs;8)&nbs;|&nbs;'o')</code>.
746      *
747      * @exception NullPointerException if the given pattern is null
748      * @exception IllegalArgumentException if the given pattern is invalid
749      */
750     private char[] compile(String pattern) {
751         int length = pattern.length();
752         boolean inQuote = false;
753         StringBuilder compiledPattern = new StringBuilder(length * 2);
754         StringBuilder tmpBuffer = null;
755         int count = 0;
756         int lastTag = -1;
757 
758         for (int i = 0; i < length; i++) {
759             char c = pattern.charAt(i);
760 
761             if (c == '\'') {
762                 // '' is treated as a single quote regardless of being
763                 // in a quoted section.
764                 if ((i + 1) < length) {
765                     c = pattern.charAt(i + 1);
766                     if (c == '\'') {
767                         i++;
768                         if (count != 0) {
769                             encode(lastTag, count, compiledPattern);
770                             lastTag = -1;
771                             count = 0;
772                         }
773                         if (inQuote) {
774                             tmpBuffer.append(c);
775                         } else {
776                             compiledPattern.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));
777                         }
778                         continue;
779                     }
780                 }
781                 if (!inQuote) {
782                     if (count != 0) {
783                         encode(lastTag, count, compiledPattern);
784                         lastTag = -1;
785                         count = 0;
786                     }
787                     if (tmpBuffer == null) {
788                         tmpBuffer = new StringBuilder(length);
789                     } else {
790                         tmpBuffer.setLength(0);
791                     }
792                     inQuote = true;
793                 } else {
794                     int len = tmpBuffer.length();
795                     if (len == 1) {
796                         char ch = tmpBuffer.charAt(0);
797                         if (ch < 128) {
798                             compiledPattern.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | ch));
799                         } else {
800                             compiledPattern.append((char)(TAG_QUOTE_CHARS << 8 | 1));
801                             compiledPattern.append(ch);
802                         }
803                     } else {
804                         encode(TAG_QUOTE_CHARS, len, compiledPattern);
805                         compiledPattern.append(tmpBuffer);
806                     }
807                     inQuote = false;
808                 }
809                 continue;
810             }
811             if (inQuote) {
812                 tmpBuffer.append(c);
813                 continue;
814             }
815             if (!(c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z')) {
816                 if (count != 0) {
817                     encode(lastTag, count, compiledPattern);
818                     lastTag = -1;
819                     count = 0;
820                 }
821                 if (c < 128) {
822                     // In most cases, c would be a delimiter, such as ':'.
823                     compiledPattern.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));
824                 } else {
825                     // Take any contiguous non-ASCII alphabet characters and
826                     // put them in a single TAG_QUOTE_CHARS.
827                     int j;
828                     for (j = i + 1; j < length; j++) {
829                         char d = pattern.charAt(j);
830                         if (d == '\'' || (d >= 'a' && d <= 'z' || d >= 'A' && d <= 'Z')) {
831                             break;
832                         }
833                     }
834                     compiledPattern.append((char)(TAG_QUOTE_CHARS << 8 | (j - i)));
835                     for (; i < j; i++) {
836                         compiledPattern.append(pattern.charAt(i));
837                     }
838                     i--;
839                 }
840                 continue;
841             }
842 
843             int tag;
844             if ((tag = DateFormatSymbols.patternChars.indexOf(c)) == -1) {
845                 throw new IllegalArgumentException("Illegal pattern character " +
846                                                    "'" + c + "'");
847             }
848             if (lastTag == -1 || lastTag == tag) {
849                 lastTag = tag;
850                 count++;
851                 continue;
852             }
853             encode(lastTag, count, compiledPattern);
854             lastTag = tag;
855             count = 1;
856         }
857 
858         if (inQuote) {
859             throw new IllegalArgumentException("Unterminated quote");
860         }
861 
862         if (count != 0) {
863             encode(lastTag, count, compiledPattern);
864         }
865 
866         // Copy the compiled pattern to a char array
867         int len = compiledPattern.length();
868         char[] r = new char[len];
869         compiledPattern.getChars(0, len, r, 0);
870         return r;
871     }
872 
873     /**
874      * Encodes the given tag and length and puts encoded char(s) into buffer.
875      */
876     private static final void encode(int tag, int length, StringBuilder buffer) {
877         if (tag == PATTERN_ISO_ZONE && length >= 4) {
878             throw new IllegalArgumentException("invalid ISO 8601 format: length=" + length);
879         }
880         if (length < 255) {
881             buffer.append((char)(tag << 8 | length));
882         } else {
883             buffer.append((char)((tag << 8) | 0xff));
884             buffer.append((char)(length >>> 16));
885             buffer.append((char)(length & 0xffff));
886         }
887     }
888 
889     /* Initialize the fields we use to disambiguate ambiguous years. Separate
890      * so we can call it from readObject().
891      */
892     private void initializeDefaultCentury() {
893         calendar.setTimeInMillis(System.currentTimeMillis());
894         calendar.add( Calendar.YEAR, -80 );
895         parseAmbiguousDatesAsAfter(calendar.getTime());
896     }
897 
898     /* Define one-century window into which to disambiguate dates using
899      * two-digit years.
900      */
901     private void parseAmbiguousDatesAsAfter(Date startDate) {
902         defaultCenturyStart = startDate;
903         calendar.setTime(startDate);
904         defaultCenturyStartYear = calendar.get(Calendar.YEAR);
905     }
906 
907     /**
908      * Sets the 100-year period 2-digit years will be interpreted as being in
909      * to begin on the date the user specifies.
910      *
911      * @param startDate During parsing, two digit years will be placed in the range
912      * <code>startDate</code> to <code>startDate + 100 years</code>.
913      * @see #get2DigitYearStart
914      * @since 1.2
915      */
916     public void set2DigitYearStart(Date startDate) {
917         parseAmbiguousDatesAsAfter(new Date(startDate.getTime()));
918     }
919 
920     /**
921      * Returns the beginning date of the 100-year period 2-digit years are interpreted
922      * as being within.
923      *
924      * @return the start of the 100-year period into which two digit years are
925      * parsed
926      * @see #set2DigitYearStart
927      * @since 1.2
928      */
929     public Date get2DigitYearStart() {
930         return (Date) defaultCenturyStart.clone();
931     }
932 
933     /**
934      * Formats the given <code>Date</code> into a date/time string and appends
935      * the result to the given <code>StringBuffer</code>.
936      *
937      * @param date the date-time value to be formatted into a date-time string.
938      * @param toAppendTo where the new date-time text is to be appended.
939      * @param pos the formatting position. On input: an alignment field,
940      * if desired. On output: the offsets of the alignment field.
941      * @return the formatted date-time string.
942      * @exception NullPointerException if the given {@code date} is {@code null}.
943      */
944     public StringBuffer format(Date date, StringBuffer toAppendTo,
945                                FieldPosition pos)
946     {
947         pos.beginIndex = pos.endIndex = 0;
948         return format(date, toAppendTo, pos.getFieldDelegate());
949     }
950 
951     // Called from Format after creating a FieldDelegate
952     private StringBuffer format(Date date, StringBuffer toAppendTo,
953                                 FieldDelegate delegate) {
954         // Convert input date to time field list
955         calendar.setTime(date);
956 
957         boolean useDateFormatSymbols = useDateFormatSymbols();
958 
959         for (int i = 0; i < compiledPattern.length; ) {
960             int tag = compiledPattern[i] >>> 8;
961             int count = compiledPattern[i++] & 0xff;
962             if (count == 255) {
963                 count = compiledPattern[i++] << 16;
964                 count |= compiledPattern[i++];
965             }
966 
967             switch (tag) {
968             case TAG_QUOTE_ASCII_CHAR:
969                 toAppendTo.append((char)count);
970                 break;
971 
972             case TAG_QUOTE_CHARS:
973                 toAppendTo.append(compiledPattern, i, count);
974                 i += count;
975                 break;
976 
977             default:
978                 subFormat(tag, count, delegate, toAppendTo, useDateFormatSymbols);
979                 break;
980             }
981         }
982         return toAppendTo;
983     }
984 
985     /**
986      * Formats an Object producing an <code>AttributedCharacterIterator</code>.
987      * You can use the returned <code>AttributedCharacterIterator</code>
988      * to build the resulting String, as well as to determine information
989      * about the resulting String.
990      * <p>
991      * Each attribute key of the AttributedCharacterIterator will be of type
992      * <code>DateFormat.Field</code>, with the corresponding attribute value
993      * being the same as the attribute key.
994      *
995      * @exception NullPointerException if obj is null.
996      * @exception IllegalArgumentException if the Format cannot format the
997      *            given object, or if the Format's pattern string is invalid.
998      * @param obj The object to format
999      * @return AttributedCharacterIterator describing the formatted value.
1000      * @since 1.4
1001      */
1002     public AttributedCharacterIterator formatToCharacterIterator(Object obj) {
1003         StringBuffer sb = new StringBuffer();
1004         CharacterIteratorFieldDelegate delegate = new
1005                          CharacterIteratorFieldDelegate();
1006 
1007         if (obj instanceof Date) {
1008             format((Date)obj, sb, delegate);
1009         }
1010         else if (obj instanceof Number) {
1011             format(new Date(((Number)obj).longValue()), sb, delegate);
1012         }
1013         else if (obj == null) {
1014             throw new NullPointerException(
1015                    "formatToCharacterIterator must be passed non-null object");
1016         }
1017         else {
1018             throw new IllegalArgumentException(
1019                              "Cannot format given Object as a Date");
1020         }
1021         return delegate.getIterator(sb.toString());
1022     }
1023 
1024     // Map index into pattern character string to Calendar field number
1025     private static final int[] PATTERN_INDEX_TO_CALENDAR_FIELD =
1026     {
1027         Calendar.ERA, Calendar.YEAR, Calendar.MONTH, Calendar.DATE,
1028         Calendar.HOUR_OF_DAY, Calendar.HOUR_OF_DAY, Calendar.MINUTE,
1029         Calendar.SECOND, Calendar.MILLISECOND, Calendar.DAY_OF_WEEK,
1030         Calendar.DAY_OF_YEAR, Calendar.DAY_OF_WEEK_IN_MONTH,
1031         Calendar.WEEK_OF_YEAR, Calendar.WEEK_OF_MONTH,
1032         Calendar.AM_PM, Calendar.HOUR, Calendar.HOUR, Calendar.ZONE_OFFSET,
1033         Calendar.ZONE_OFFSET,
1034         // Pseudo Calendar fields
1035         CalendarBuilder.WEEK_YEAR,
1036         CalendarBuilder.ISO_DAY_OF_WEEK,
1037         Calendar.ZONE_OFFSET
1038     };
1039 
1040     // Map index into pattern character string to DateFormat field number
1041     private static final int[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD = {
1042         DateFormat.ERA_FIELD, DateFormat.YEAR_FIELD, DateFormat.MONTH_FIELD,
1043         DateFormat.DATE_FIELD, DateFormat.HOUR_OF_DAY1_FIELD,
1044         DateFormat.HOUR_OF_DAY0_FIELD, DateFormat.MINUTE_FIELD,
1045         DateFormat.SECOND_FIELD, DateFormat.MILLISECOND_FIELD,
1046         DateFormat.DAY_OF_WEEK_FIELD, DateFormat.DAY_OF_YEAR_FIELD,
1047         DateFormat.DAY_OF_WEEK_IN_MONTH_FIELD, DateFormat.WEEK_OF_YEAR_FIELD,
1048         DateFormat.WEEK_OF_MONTH_FIELD, DateFormat.AM_PM_FIELD,
1049         DateFormat.HOUR1_FIELD, DateFormat.HOUR0_FIELD,
1050         DateFormat.TIMEZONE_FIELD, DateFormat.TIMEZONE_FIELD,
1051         DateFormat.YEAR_FIELD, DateFormat.DAY_OF_WEEK_FIELD,
1052         DateFormat.TIMEZONE_FIELD
1053     };
1054 
1055     // Maps from DecimalFormatSymbols index to Field constant
1056     private static final Field[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID = {
1057         Field.ERA, Field.YEAR, Field.MONTH, Field.DAY_OF_MONTH,
1058         Field.HOUR_OF_DAY1, Field.HOUR_OF_DAY0, Field.MINUTE,
1059         Field.SECOND, Field.MILLISECOND, Field.DAY_OF_WEEK,
1060         Field.DAY_OF_YEAR, Field.DAY_OF_WEEK_IN_MONTH,
1061         Field.WEEK_OF_YEAR, Field.WEEK_OF_MONTH,
1062         Field.AM_PM, Field.HOUR1, Field.HOUR0, Field.TIME_ZONE,
1063         Field.TIME_ZONE,
1064         Field.YEAR, Field.DAY_OF_WEEK,
1065         Field.TIME_ZONE
1066     };
1067 
1068     /**
1069      * Private member function that does the real date/time formatting.
1070      */
1071     private void subFormat(int patternCharIndex, int count,
1072                            FieldDelegate delegate, StringBuffer buffer,
1073                            boolean useDateFormatSymbols)
1074     {
1075         int     maxIntCount = Integer.MAX_VALUE;
1076         String  current = null;
1077         int     beginOffset = buffer.length();
1078 
1079         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1080         int value;
1081         if (field == CalendarBuilder.WEEK_YEAR) {
1082             if (calendar.isWeekDateSupported()) {
1083                 value = calendar.getWeekYear();
1084             } else {
1085                 // use calendar year 'y' instead
1086                 patternCharIndex = PATTERN_YEAR;
1087                 field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1088                 value = calendar.get(field);
1089             }
1090         } else if (field == CalendarBuilder.ISO_DAY_OF_WEEK) {
1091             value = CalendarBuilder.toISODayOfWeek(calendar.get(Calendar.DAY_OF_WEEK));
1092         } else {
1093             value = calendar.get(field);
1094         }
1095 
1096         int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1097         if (!useDateFormatSymbols && field != CalendarBuilder.ISO_DAY_OF_WEEK) {
1098             current = calendar.getDisplayName(field, style, locale);
1099         }
1100 
1101         // Note: zeroPaddingNumber() assumes that maxDigits is either
1102         // 2 or maxIntCount. If we make any changes to this,
1103         // zeroPaddingNumber() must be fixed.
1104 
1105         switch (patternCharIndex) {
1106         case PATTERN_ERA: // 'G'
1107             if (useDateFormatSymbols) {
1108                 String[] eras = formatData.getEras();
1109                 if (value < eras.length)
1110                     current = eras[value];
1111             }
1112             if (current == null)
1113                 current = "";
1114             break;
1115 
1116         case PATTERN_WEEK_YEAR: // 'Y'
1117         case PATTERN_YEAR:      // 'y'
1118             if (calendar instanceof GregorianCalendar) {
1119                 if (count != 2)
1120                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1121                 else // count == 2
1122                     zeroPaddingNumber(value, 2, 2, buffer); // clip 1996 to 96
1123             } else {
1124                 if (current == null) {
1125                     zeroPaddingNumber(value, style == Calendar.LONG ? 1 : count,
1126                                       maxIntCount, buffer);
1127                 }
1128             }
1129             break;
1130 
1131         case PATTERN_MONTH: // 'M'
1132             if (useDateFormatSymbols) {
1133                 String[] months;
1134                 if (count >= 4) {
1135                     months = formatData.getMonths();
1136                     current = months[value];
1137                 } else if (count == 3) {
1138                     months = formatData.getShortMonths();
1139                     current = months[value];
1140                 }
1141             } else {
1142                 if (count < 3) {
1143                     current = null;
1144                 }
1145             }
1146             if (current == null) {
1147                 zeroPaddingNumber(value+1, count, maxIntCount, buffer);
1148             }
1149             break;
1150 
1151         case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
1152             if (current == null) {
1153                 if (value == 0)
1154                     zeroPaddingNumber(calendar.getMaximum(Calendar.HOUR_OF_DAY)+1,
1155                                       count, maxIntCount, buffer);
1156                 else
1157                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1158             }
1159             break;
1160 
1161         case PATTERN_DAY_OF_WEEK: // 'E'
1162             if (useDateFormatSymbols) {
1163                 String[] weekdays;
1164                 if (count >= 4) {
1165                     weekdays = formatData.getWeekdays();
1166                     current = weekdays[value];
1167                 } else { // count < 4, use abbreviated form if exists
1168                     weekdays = formatData.getShortWeekdays();
1169                     current = weekdays[value];
1170                 }
1171             }
1172             break;
1173 
1174         case PATTERN_AM_PM:    // 'a'
1175             if (useDateFormatSymbols) {
1176                 String[] ampm = formatData.getAmPmStrings();
1177                 current = ampm[value];
1178             }
1179             break;
1180 
1181         case PATTERN_HOUR1:    // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
1182             if (current == null) {
1183                 if (value == 0)
1184                     zeroPaddingNumber(calendar.getLeastMaximum(Calendar.HOUR)+1,
1185                                       count, maxIntCount, buffer);
1186                 else
1187                     zeroPaddingNumber(value, count, maxIntCount, buffer);
1188             }
1189             break;
1190 
1191         case PATTERN_ZONE_NAME: // 'z'
1192             if (current == null) {
1193                 if (formatData.locale == null || formatData.isZoneStringsSet) {
1194                     int zoneIndex =
1195                         formatData.getZoneIndex(calendar.getTimeZone().getID());
1196                     if (zoneIndex == -1) {
1197                         value = calendar.get(Calendar.ZONE_OFFSET) +
1198                             calendar.get(Calendar.DST_OFFSET);
1199                         buffer.append(ZoneInfoFile.toCustomID(value));
1200                     } else {
1201                         int index = (calendar.get(Calendar.DST_OFFSET) == 0) ? 1: 3;
1202                         if (count < 4) {
1203                             // Use the short name
1204                             index++;
1205                         }
1206                         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1207                         buffer.append(zoneStrings[zoneIndex][index]);
1208                     }
1209                 } else {
1210                     TimeZone tz = calendar.getTimeZone();
1211                     boolean daylight = (calendar.get(Calendar.DST_OFFSET) != 0);
1212                     int tzstyle = (count < 4 ? TimeZone.SHORT : TimeZone.LONG);
1213                     buffer.append(tz.getDisplayName(daylight, tzstyle, formatData.locale));
1214                 }
1215             }
1216             break;
1217 
1218         case PATTERN_ZONE_VALUE: // 'Z' ("-/+hhmm" form)
1219             value = (calendar.get(Calendar.ZONE_OFFSET) +
1220                      calendar.get(Calendar.DST_OFFSET)) / 60000;
1221 
1222             int width = 4;
1223             if (value >= 0) {
1224                 buffer.append('+');
1225             } else {
1226                 width++;
1227             }
1228 
1229             int num = (value / 60) * 100 + (value % 60);
1230             CalendarUtils.sprintf0d(buffer, num, width);
1231             break;
1232 
1233         case PATTERN_ISO_ZONE:   // 'X'
1234             value = calendar.get(Calendar.ZONE_OFFSET)
1235                     + calendar.get(Calendar.DST_OFFSET);
1236 
1237             if (value == 0) {
1238                 buffer.append('Z');
1239                 break;
1240             }
1241 
1242             value /=  60000;
1243             if (value >= 0) {
1244                 buffer.append('+');
1245             } else {
1246                 buffer.append('-');
1247                 value = -value;
1248             }
1249 
1250             CalendarUtils.sprintf0d(buffer, value / 60, 2);
1251             if (count == 1) {
1252                 break;
1253             }
1254 
1255             if (count == 3) {
1256                 buffer.append(':');
1257             }
1258             CalendarUtils.sprintf0d(buffer, value % 60, 2);
1259             break;
1260 
1261         default:
1262      // case PATTERN_DAY_OF_MONTH:         // 'd'
1263      // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
1264      // case PATTERN_MINUTE:               // 'm'
1265      // case PATTERN_SECOND:               // 's'
1266      // case PATTERN_MILLISECOND:          // 'S'
1267      // case PATTERN_DAY_OF_YEAR:          // 'D'
1268      // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
1269      // case PATTERN_WEEK_OF_YEAR:         // 'w'
1270      // case PATTERN_WEEK_OF_MONTH:        // 'W'
1271      // case PATTERN_HOUR0:                // 'K' eg, 11PM + 1 hour =>> 0 AM
1272      // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' pseudo field, Monday = 1, ..., Sunday = 7
1273             if (current == null) {
1274                 zeroPaddingNumber(value, count, maxIntCount, buffer);
1275             }
1276             break;
1277         } // switch (patternCharIndex)
1278 
1279         if (current != null) {
1280             buffer.append(current);
1281         }
1282 
1283         int fieldID = PATTERN_INDEX_TO_DATE_FORMAT_FIELD[patternCharIndex];
1284         Field f = PATTERN_INDEX_TO_DATE_FORMAT_FIELD_ID[patternCharIndex];
1285 
1286         delegate.formatted(fieldID, f, f, beginOffset, buffer.length(), buffer);
1287     }
1288 
1289     /**
1290      * Formats a number with the specified minimum and maximum number of digits.
1291      */
1292     private final void zeroPaddingNumber(int value, int minDigits, int maxDigits, StringBuffer buffer)
1293     {
1294         // Optimization for 1, 2 and 4 digit numbers. This should
1295         // cover most cases of formatting date/time related items.
1296         // Note: This optimization code assumes that maxDigits is
1297         // either 2 or Integer.MAX_VALUE (maxIntCount in format()).
1298         try {
1299             if (zeroDigit == 0) {
1300                 zeroDigit = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getZeroDigit();
1301             }
1302             if (value >= 0) {
1303                 if (value < 100 && minDigits >= 1 && minDigits <= 2) {
1304                     if (value < 10) {
1305                         if (minDigits == 2) {
1306                             buffer.append(zeroDigit);
1307                         }
1308                         buffer.append((char)(zeroDigit + value));
1309                     } else {
1310                         buffer.append((char)(zeroDigit + value / 10));
1311                         buffer.append((char)(zeroDigit + value % 10));
1312                     }
1313                     return;
1314                 } else if (value >= 1000 && value < 10000) {
1315                     if (minDigits == 4) {
1316                         buffer.append((char)(zeroDigit + value / 1000));
1317                         value %= 1000;
1318                         buffer.append((char)(zeroDigit + value / 100));
1319                         value %= 100;
1320                         buffer.append((char)(zeroDigit + value / 10));
1321                         buffer.append((char)(zeroDigit + value % 10));
1322                         return;
1323                     }
1324                     if (minDigits == 2 && maxDigits == 2) {
1325                         zeroPaddingNumber(value % 100, 2, 2, buffer);
1326                         return;
1327                     }
1328                 }
1329             }
1330         } catch (Exception e) {
1331         }
1332 
1333         numberFormat.setMinimumIntegerDigits(minDigits);
1334         numberFormat.setMaximumIntegerDigits(maxDigits);
1335         numberFormat.format((long)value, buffer, DontCareFieldPosition.INSTANCE);
1336     }
1337 
1338 
1339     /**
1340      * Parses text from a string to produce a <code>Date</code>.
1341      * <p>
1342      * The method attempts to parse text starting at the index given by
1343      * <code>pos</code>.
1344      * If parsing succeeds, then the index of <code>pos</code> is updated
1345      * to the index after the last character used (parsing does not necessarily
1346      * use all characters up to the end of the string), and the parsed
1347      * date is returned. The updated <code>pos</code> can be used to
1348      * indicate the starting point for the next call to this method.
1349      * If an error occurs, then the index of <code>pos</code> is not
1350      * changed, the error index of <code>pos</code> is set to the index of
1351      * the character where the error occurred, and null is returned.
1352      *
1353      * <p>This parsing operation uses the {@link DateFormat#calendar
1354      * calendar} to produce a {@code Date}. All of the {@code
1355      * calendar}'s date-time fields are {@linkplain Calendar#clear()
1356      * cleared} before parsing, and the {@code calendar}'s default
1357      * values of the date-time fields are used for any missing
1358      * date-time information. For example, the year value of the
1359      * parsed {@code Date} is 1970 with {@link GregorianCalendar} if
1360      * no year value is given from the parsing operation.  The {@code
1361      * TimeZone} value may be overwritten, depending on the given
1362      * pattern and the time zone value in {@code text}. Any {@code
1363      * TimeZone} value that has previously been set by a call to
1364      * {@link #setTimeZone(java.util.TimeZone) setTimeZone} may need
1365      * to be restored for further operations.
1366      *
1367      * @param text  A <code>String</code>, part of which should be parsed.
1368      * @param pos   A <code>ParsePosition</code> object with index and error
1369      *              index information as described above.
1370      * @return A <code>Date</code> parsed from the string. In case of
1371      *         error, returns null.
1372      * @exception NullPointerException if <code>text</code> or <code>pos</code> is null.
1373      */
1374     public Date parse(String text, ParsePosition pos)
1375     {
1376         checkNegativeNumberExpression();
1377 
1378         int start = pos.index;
1379         int oldStart = start;
1380         int textLength = text.length();
1381 
1382         boolean[] ambiguousYear = {false};
1383 
1384         CalendarBuilder calb = new CalendarBuilder();
1385 
1386         for (int i = 0; i < compiledPattern.length; ) {
1387             int tag = compiledPattern[i] >>> 8;
1388             int count = compiledPattern[i++] & 0xff;
1389             if (count == 255) {
1390                 count = compiledPattern[i++] << 16;
1391                 count |= compiledPattern[i++];
1392             }
1393 
1394             switch (tag) {
1395             case TAG_QUOTE_ASCII_CHAR:
1396                 if (start >= textLength || text.charAt(start) != (char)count) {
1397                     pos.index = oldStart;
1398                     pos.errorIndex = start;
1399                     return null;
1400                 }
1401                 start++;
1402                 break;
1403 
1404             case TAG_QUOTE_CHARS:
1405                 while (count-- > 0) {
1406                     if (start >= textLength || text.charAt(start) != compiledPattern[i++]) {
1407                         pos.index = oldStart;
1408                         pos.errorIndex = start;
1409                         return null;
1410                     }
1411                     start++;
1412                 }
1413                 break;
1414 
1415             default:
1416                 // Peek the next pattern to determine if we need to
1417                 // obey the number of pattern letters for
1418                 // parsing. It's required when parsing contiguous
1419                 // digit text (e.g., "20010704") with a pattern which
1420                 // has no delimiters between fields, like "yyyyMMdd".
1421                 boolean obeyCount = false;
1422 
1423                 // In Arabic, a minus sign for a negative number is put after
1424                 // the number. Even in another locale, a minus sign can be
1425                 // put after a number using DateFormat.setNumberFormat().
1426                 // If both the minus sign and the field-delimiter are '-',
1427                 // subParse() needs to determine whether a '-' after a number
1428                 // in the given text is a delimiter or is a minus sign for the
1429                 // preceding number. We give subParse() a clue based on the
1430                 // information in compiledPattern.
1431                 boolean useFollowingMinusSignAsDelimiter = false;
1432 
1433                 if (i < compiledPattern.length) {
1434                     int nextTag = compiledPattern[i] >>> 8;
1435                     if (!(nextTag == TAG_QUOTE_ASCII_CHAR ||
1436                           nextTag == TAG_QUOTE_CHARS)) {
1437                         obeyCount = true;
1438                     }
1439 
1440                     if (hasFollowingMinusSign &&
1441                         (nextTag == TAG_QUOTE_ASCII_CHAR ||
1442                          nextTag == TAG_QUOTE_CHARS)) {
1443                         int c;
1444                         if (nextTag == TAG_QUOTE_ASCII_CHAR) {
1445                             c = compiledPattern[i] & 0xff;
1446                         } else {
1447                             c = compiledPattern[i+1];
1448                         }
1449 
1450                         if (c == minusSign) {
1451                             useFollowingMinusSignAsDelimiter = true;
1452                         }
1453                     }
1454                 }
1455                 start = subParse(text, start, tag, count, obeyCount,
1456                                  ambiguousYear, pos,
1457                                  useFollowingMinusSignAsDelimiter, calb);
1458                 if (start < 0) {
1459                     pos.index = oldStart;
1460                     return null;
1461                 }
1462             }
1463         }
1464 
1465         // At this point the fields of Calendar have been set.  Calendar
1466         // will fill in default values for missing fields when the time
1467         // is computed.
1468 
1469         pos.index = start;
1470 
1471         Date parsedDate;
1472         try {
1473             parsedDate = calb.establish(calendar).getTime();
1474             // If the year value is ambiguous,
1475             // then the two-digit year == the default start year
1476             if (ambiguousYear[0]) {
1477                 if (parsedDate.before(defaultCenturyStart)) {
1478                     parsedDate = calb.addYear(100).establish(calendar).getTime();
1479                 }
1480             }
1481         }
1482         // An IllegalArgumentException will be thrown by Calendar.getTime()
1483         // if any fields are out of range, e.g., MONTH == 17.
1484         catch (IllegalArgumentException e) {
1485             pos.errorIndex = start;
1486             pos.index = oldStart;
1487             return null;
1488         }
1489 
1490         return parsedDate;
1491     }
1492 
1493     /**
1494      * Private code-size reduction function used by subParse.
1495      * @param text the time text being parsed.
1496      * @param start where to start parsing.
1497      * @param field the date field being parsed.
1498      * @param data the string array to parsed.
1499      * @return the new start position if matching succeeded; a negative number
1500      * indicating matching failure, otherwise.
1501      */
1502     private int matchString(String text, int start, int field, String[] data, CalendarBuilder calb)
1503     {
1504         int i = 0;
1505         int count = data.length;
1506 
1507         if (field == Calendar.DAY_OF_WEEK) i = 1;
1508 
1509         // There may be multiple strings in the data[] array which begin with
1510         // the same prefix (e.g., Cerven and Cervenec (June and July) in Czech).
1511         // We keep track of the longest match, and return that.  Note that this
1512         // unfortunately requires us to test all array elements.
1513         int bestMatchLength = 0, bestMatch = -1;
1514         for (; i<count; ++i)
1515         {
1516             int length = data[i].length();
1517             // Always compare if we have no match yet; otherwise only compare
1518             // against potentially better matches (longer strings).
1519             if (length > bestMatchLength &&
1520                 text.regionMatches(true, start, data[i], 0, length))
1521             {
1522                 bestMatch = i;
1523                 bestMatchLength = length;
1524             }
1525         }
1526         if (bestMatch >= 0)
1527         {
1528             calb.set(field, bestMatch);
1529             return start + bestMatchLength;
1530         }
1531         return -start;
1532     }
1533 
1534     /**
1535      * Performs the same thing as matchString(String, int, int,
1536      * String[]). This method takes a Map<String, Integer> instead of
1537      * String[].
1538      */
1539     private int matchString(String text, int start, int field,
1540                             Map<String,Integer> data, CalendarBuilder calb) {
1541         if (data != null) {
1542             String bestMatch = null;
1543 
1544             for (String name : data.keySet()) {
1545                 int length = name.length();
1546                 if (bestMatch == null || length > bestMatch.length()) {
1547                     if (text.regionMatches(true, start, name, 0, length)) {
1548                         bestMatch = name;
1549                     }
1550                 }
1551             }
1552 
1553             if (bestMatch != null) {
1554                 calb.set(field, data.get(bestMatch));
1555                 return start + bestMatch.length();
1556             }
1557         }
1558         return -start;
1559     }
1560 
1561     private int matchZoneString(String text, int start, String[] zoneNames) {
1562         for (int i = 1; i <= 4; ++i) {
1563             // Checking long and short zones [1 & 2],
1564             // and long and short daylight [3 & 4].
1565             String zoneName = zoneNames[i];
1566             if (text.regionMatches(true, start,
1567                                    zoneName, 0, zoneName.length())) {
1568                 return i;
1569             }
1570         }
1571         return -1;
1572     }
1573 
1574     private boolean matchDSTString(String text, int start, int zoneIndex, int standardIndex,
1575                                    String[][] zoneStrings) {
1576         int index = standardIndex + 2;
1577         String zoneName  = zoneStrings[zoneIndex][index];
1578         if (text.regionMatches(true, start,
1579                                zoneName, 0, zoneName.length())) {
1580             return true;
1581         }
1582         return false;
1583     }
1584 
1585     /**
1586      * find time zone 'text' matched zoneStrings and set to internal
1587      * calendar.
1588      */
1589     private int subParseZoneString(String text, int start, CalendarBuilder calb) {
1590         boolean useSameName = false; // true if standard and daylight time use the same abbreviation.
1591         TimeZone currentTimeZone = getTimeZone();
1592 
1593         // At this point, check for named time zones by looking through
1594         // the locale data from the TimeZoneNames strings.
1595         // Want to be able to parse both short and long forms.
1596         int zoneIndex = formatData.getZoneIndex(currentTimeZone.getID());
1597         TimeZone tz = null;
1598         String[][] zoneStrings = formatData.getZoneStringsWrapper();
1599         String[] zoneNames = null;
1600         int nameIndex = 0;
1601         if (zoneIndex != -1) {
1602             zoneNames = zoneStrings[zoneIndex];
1603             if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1604                 if (nameIndex <= 2) {
1605                     // Check if the standard name (abbr) and the daylight name are the same.
1606                     useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1607                 }
1608                 tz = TimeZone.getTimeZone(zoneNames[0]);
1609             }
1610         }
1611         if (tz == null) {
1612             zoneIndex = formatData.getZoneIndex(TimeZone.getDefault().getID());
1613             if (zoneIndex != -1) {
1614                 zoneNames = zoneStrings[zoneIndex];
1615                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1616                     if (nameIndex <= 2) {
1617                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1618                     }
1619                     tz = TimeZone.getTimeZone(zoneNames[0]);
1620                 }
1621             }
1622         }
1623 
1624         if (tz == null) {
1625             int len = zoneStrings.length;
1626             for (int i = 0; i < len; i++) {
1627                 zoneNames = zoneStrings[i];
1628                 if ((nameIndex = matchZoneString(text, start, zoneNames)) > 0) {
1629                     if (nameIndex <= 2) {
1630                         useSameName = zoneNames[nameIndex].equalsIgnoreCase(zoneNames[nameIndex + 2]);
1631                     }
1632                     tz = TimeZone.getTimeZone(zoneNames[0]);
1633                     break;
1634                 }
1635             }
1636         }
1637         if (tz != null) { // Matched any ?
1638             if (!tz.equals(currentTimeZone)) {
1639                 setTimeZone(tz);
1640             }
1641             // If the time zone matched uses the same name
1642             // (abbreviation) for both standard and daylight time,
1643             // let the time zone in the Calendar decide which one.
1644             //
1645             // Also if tz.getDSTSaving() returns 0 for DST, use tz to
1646             // determine the local time. (6645292)
1647             int dstAmount = (nameIndex >= 3) ? tz.getDSTSavings() : 0;
1648             if (!(useSameName || (nameIndex >= 3 && dstAmount == 0))) {
1649                 calb.set(Calendar.ZONE_OFFSET, tz.getRawOffset())
1650                     .set(Calendar.DST_OFFSET, dstAmount);
1651             }
1652             return (start + zoneNames[nameIndex].length());
1653         }
1654         return 0;
1655     }
1656 
1657     /**
1658      * Parses numeric forms of time zone offset, such as "hh:mm", and
1659      * sets calb to the parsed value.
1660      *
1661      * @param text  the text to be parsed
1662      * @param start the character position to start parsing
1663      * @param sign  1: positive; -1: negative
1664      * @param count 0: 'Z' or "GMT+hh:mm" parsing; 1 - 3: the number of 'X's
1665      * @param colon true - colon required between hh and mm; false - no colon required
1666      * @param calb  a CalendarBuilder in which the parsed value is stored
1667      * @return updated parsed position, or its negative value to indicate a parsing error
1668      */
1669     private int subParseNumericZone(String text, int start, int sign, int count,
1670                                     boolean colon, CalendarBuilder calb) {
1671         int index = start;
1672 
1673       parse:
1674         try {
1675             char c = text.charAt(index++);
1676             // Parse hh
1677             int hours;
1678             if (!isDigit(c)) {
1679                 break parse;
1680             }
1681             hours = c - '0';
1682             c = text.charAt(index++);
1683             if (isDigit(c)) {
1684                 hours = hours * 10 + (c - '0');
1685             } else {
1686                 // If no colon in RFC 822 or 'X' (ISO), two digits are
1687                 // required.
1688                 if (count > 0 || !colon) {
1689                     break parse;
1690                 }
1691                 --index;
1692             }
1693             if (hours > 23) {
1694                 break parse;
1695             }
1696             int minutes = 0;
1697             if (count != 1) {
1698                 // Proceed with parsing mm
1699                 c = text.charAt(index++);
1700                 if (colon) {
1701                     if (c != ':') {
1702                         break parse;
1703                     }
1704                     c = text.charAt(index++);
1705                 }
1706                 if (!isDigit(c)) {
1707                     break parse;
1708                 }
1709                 minutes = c - '0';
1710                 c = text.charAt(index++);
1711                 if (!isDigit(c)) {
1712                     break parse;
1713                 }
1714                 minutes = minutes * 10 + (c - '0');
1715                 if (minutes > 59) {
1716                     break parse;
1717                 }
1718             }
1719             minutes += hours * 60;
1720             calb.set(Calendar.ZONE_OFFSET, minutes * MILLIS_PER_MINUTE * sign)
1721                 .set(Calendar.DST_OFFSET, 0);
1722             return index;
1723         } catch (IndexOutOfBoundsException e) {
1724         }
1725         return  1 - index; // -(index - 1)
1726     }
1727 
1728     private boolean isDigit(char c) {
1729         return c >= '0' && c <= '9';
1730     }
1731 
1732     /**
1733      * Private member function that converts the parsed date strings into
1734      * timeFields. Returns -start (for ParsePosition) if failed.
1735      * @param text the time text to be parsed.
1736      * @param start where to start parsing.
1737      * @param ch the pattern character for the date field text to be parsed.
1738      * @param count the count of a pattern character.
1739      * @param obeyCount if true, then the next field directly abuts this one,
1740      * and we should use the count to know when to stop parsing.
1741      * @param ambiguousYear return parameter; upon return, if ambiguousYear[0]
1742      * is true, then a two-digit year was parsed and may need to be readjusted.
1743      * @param origPos origPos.errorIndex is used to return an error index
1744      * at which a parse error occurred, if matching failure occurs.
1745      * @return the new start position if matching succeeded; -1 indicating
1746      * matching failure, otherwise. In case matching failure occurred,
1747      * an error index is set to origPos.errorIndex.
1748      */
1749     private int subParse(String text, int start, int patternCharIndex, int count,
1750                          boolean obeyCount, boolean[] ambiguousYear,
1751                          ParsePosition origPos,
1752                          boolean useFollowingMinusSignAsDelimiter, CalendarBuilder calb) {
1753         Number number = null;
1754         int value = 0;
1755         ParsePosition pos = new ParsePosition(0);
1756         pos.index = start;
1757         if (patternCharIndex == PATTERN_WEEK_YEAR && !calendar.isWeekDateSupported()) {
1758             // use calendar year 'y' instead
1759             patternCharIndex = PATTERN_YEAR;
1760         }
1761         int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
1762 
1763         // If there are any spaces here, skip over them.  If we hit the end
1764         // of the string, then fail.
1765         for (;;) {
1766             if (pos.index >= text.length()) {
1767                 origPos.errorIndex = start;
1768                 return -1;
1769             }
1770             char c = text.charAt(pos.index);
1771             if (c != ' ' && c != '\t') break;
1772             ++pos.index;
1773         }
1774 
1775       parsing:
1776         {
1777             // We handle a few special cases here where we need to parse
1778             // a number value.  We handle further, more generic cases below.  We need
1779             // to handle some of them here because some fields require extra processing on
1780             // the parsed value.
1781             if (patternCharIndex == PATTERN_HOUR_OF_DAY1 ||
1782                 patternCharIndex == PATTERN_HOUR1 ||
1783                 (patternCharIndex == PATTERN_MONTH && count <= 2) ||
1784                 patternCharIndex == PATTERN_YEAR ||
1785                 patternCharIndex == PATTERN_WEEK_YEAR) {
1786                 // It would be good to unify this with the obeyCount logic below,
1787                 // but that's going to be difficult.
1788                 if (obeyCount) {
1789                     if ((start+count) > text.length()) {
1790                         break parsing;
1791                     }
1792                     number = numberFormat.parse(text.substring(0, start+count), pos);
1793                 } else {
1794                     number = numberFormat.parse(text, pos);
1795                 }
1796                 if (number == null) {
1797                     if (patternCharIndex != PATTERN_YEAR || calendar instanceof GregorianCalendar) {
1798                         break parsing;
1799                     }
1800                 } else {
1801                     value = number.intValue();
1802 
1803                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
1804                         (((pos.index < text.length()) &&
1805                          (text.charAt(pos.index) != minusSign)) ||
1806                          ((pos.index == text.length()) &&
1807                           (text.charAt(pos.index-1) == minusSign)))) {
1808                         value = -value;
1809                         pos.index--;
1810                     }
1811                 }
1812             }
1813 
1814             boolean useDateFormatSymbols = useDateFormatSymbols();
1815 
1816             int index;
1817             switch (patternCharIndex) {
1818             case PATTERN_ERA: // 'G'
1819                 if (useDateFormatSymbols) {
1820                     if ((index = matchString(text, start, Calendar.ERA, formatData.getEras(), calb)) > 0) {
1821                         return index;
1822                     }
1823                 } else {
1824                     Map<String, Integer> map = calendar.getDisplayNames(field,
1825                                                                         Calendar.ALL_STYLES,
1826                                                                         locale);
1827                     if ((index = matchString(text, start, field, map, calb)) > 0) {
1828                         return index;
1829                     }
1830                 }
1831                 break parsing;
1832 
1833             case PATTERN_WEEK_YEAR: // 'Y'
1834             case PATTERN_YEAR:      // 'y'
1835                 if (!(calendar instanceof GregorianCalendar)) {
1836                     // calendar might have text representations for year values,
1837                     // such as "\u5143" in JapaneseImperialCalendar.
1838                     int style = (count >= 4) ? Calendar.LONG : Calendar.SHORT;
1839                     Map<String, Integer> map = calendar.getDisplayNames(field, style, locale);
1840                     if (map != null) {
1841                         if ((index = matchString(text, start, field, map, calb)) > 0) {
1842                             return index;
1843                         }
1844                     }
1845                     calb.set(field, value);
1846                     return pos.index;
1847                 }
1848 
1849                 // If there are 3 or more YEAR pattern characters, this indicates
1850                 // that the year value is to be treated literally, without any
1851                 // two-digit year adjustments (e.g., from "01" to 2001).  Otherwise
1852                 // we made adjustments to place the 2-digit year in the proper
1853                 // century, for parsed strings from "00" to "99".  Any other string
1854                 // is treated literally:  "2250", "-1", "1", "002".
1855                 if (count <= 2 && (pos.index - start) == 2
1856                     && Character.isDigit(text.charAt(start))
1857                     && Character.isDigit(text.charAt(start+1))) {
1858                     // Assume for example that the defaultCenturyStart is 6/18/1903.
1859                     // This means that two-digit years will be forced into the range
1860                     // 6/18/1903 to 6/17/2003.  As a result, years 00, 01, and 02
1861                     // correspond to 2000, 2001, and 2002.  Years 04, 05, etc. correspond
1862                     // to 1904, 1905, etc.  If the year is 03, then it is 2003 if the
1863                     // other fields specify a date before 6/18, or 1903 if they specify a
1864                     // date afterwards.  As a result, 03 is an ambiguous year.  All other
1865                     // two-digit years are unambiguous.
1866                     int ambiguousTwoDigitYear = defaultCenturyStartYear % 100;
1867                     ambiguousYear[0] = value == ambiguousTwoDigitYear;
1868                     value += (defaultCenturyStartYear/100)*100 +
1869                         (value < ambiguousTwoDigitYear ? 100 : 0);
1870                 }
1871                 calb.set(field, value);
1872                 return pos.index;
1873 
1874             case PATTERN_MONTH: // 'M'
1875                 if (count <= 2) // i.e., M or MM.
1876                 {
1877                     // Don't want to parse the month if it is a string
1878                     // while pattern uses numeric style: M or MM.
1879                     // [We computed 'value' above.]
1880                     calb.set(Calendar.MONTH, value - 1);
1881                     return pos.index;
1882                 }
1883 
1884                 if (useDateFormatSymbols) {
1885                     // count >= 3 // i.e., MMM or MMMM
1886                     // Want to be able to parse both short and long forms.
1887                     // Try count == 4 first:
1888                     int newStart = 0;
1889                     if ((newStart = matchString(text, start, Calendar.MONTH,
1890                                                 formatData.getMonths(), calb)) > 0) {
1891                         return newStart;
1892                     }
1893                     // count == 4 failed, now try count == 3
1894                     if ((index = matchString(text, start, Calendar.MONTH,
1895                                              formatData.getShortMonths(), calb)) > 0) {
1896                         return index;
1897                     }
1898                 } else {
1899                     Map<String, Integer> map = calendar.getDisplayNames(field,
1900                                                                         Calendar.ALL_STYLES,
1901                                                                         locale);
1902                     if ((index = matchString(text, start, field, map, calb)) > 0) {
1903                         return index;
1904                     }
1905                 }
1906                 break parsing;
1907 
1908             case PATTERN_HOUR_OF_DAY1: // 'k' 1-based.  eg, 23:59 + 1 hour =>> 24:59
1909                 if (!isLenient()) {
1910                     // Validate the hour value in non-lenient
1911                     if (value < 1 || value > 24) {
1912                         break parsing;
1913                     }
1914                 }
1915                 // [We computed 'value' above.]
1916                 if (value == calendar.getMaximum(Calendar.HOUR_OF_DAY)+1)
1917                     value = 0;
1918                 calb.set(Calendar.HOUR_OF_DAY, value);
1919                 return pos.index;
1920 
1921             case PATTERN_DAY_OF_WEEK:  // 'E'
1922                 {
1923                     if (useDateFormatSymbols) {
1924                         // Want to be able to parse both short and long forms.
1925                         // Try count == 4 (DDDD) first:
1926                         int newStart = 0;
1927                         if ((newStart=matchString(text, start, Calendar.DAY_OF_WEEK,
1928                                                   formatData.getWeekdays(), calb)) > 0) {
1929                             return newStart;
1930                         }
1931                         // DDDD failed, now try DDD
1932                         if ((index = matchString(text, start, Calendar.DAY_OF_WEEK,
1933                                                  formatData.getShortWeekdays(), calb)) > 0) {
1934                             return index;
1935                         }
1936                     } else {
1937                         int[] styles = { Calendar.LONG, Calendar.SHORT };
1938                         for (int style : styles) {
1939                             Map<String,Integer> map = calendar.getDisplayNames(field, style, locale);
1940                             if ((index = matchString(text, start, field, map, calb)) > 0) {
1941                                 return index;
1942                             }
1943                         }
1944                     }
1945                 }
1946                 break parsing;
1947 
1948             case PATTERN_AM_PM:    // 'a'
1949                 if (useDateFormatSymbols) {
1950                     if ((index = matchString(text, start, Calendar.AM_PM,
1951                                              formatData.getAmPmStrings(), calb)) > 0) {
1952                         return index;
1953                     }
1954                 } else {
1955                     Map<String,Integer> map = calendar.getDisplayNames(field, Calendar.ALL_STYLES, locale);
1956                     if ((index = matchString(text, start, field, map, calb)) > 0) {
1957                         return index;
1958                     }
1959                 }
1960                 break parsing;
1961 
1962             case PATTERN_HOUR1: // 'h' 1-based.  eg, 11PM + 1 hour =>> 12 AM
1963                 if (!isLenient()) {
1964                     // Validate the hour value in non-lenient
1965                     if (value < 1 || value > 12) {
1966                         break parsing;
1967                     }
1968                 }
1969                 // [We computed 'value' above.]
1970                 if (value == calendar.getLeastMaximum(Calendar.HOUR)+1)
1971                     value = 0;
1972                 calb.set(Calendar.HOUR, value);
1973                 return pos.index;
1974 
1975             case PATTERN_ZONE_NAME:  // 'z'
1976             case PATTERN_ZONE_VALUE: // 'Z'
1977                 {
1978                     int sign = 0;
1979                     try {
1980                         char c = text.charAt(pos.index);
1981                         if (c == '+') {
1982                             sign = 1;
1983                         } else if (c == '-') {
1984                             sign = -1;
1985                         }
1986                         if (sign == 0) {
1987                             // Try parsing a custom time zone "GMT+hh:mm" or "GMT".
1988                             if ((c == 'G' || c == 'g')
1989                                 && (text.length() - start) >= GMT.length()
1990                                 && text.regionMatches(true, start, GMT, 0, GMT.length())) {
1991                                 pos.index = start + GMT.length();
1992 
1993                                 if ((text.length() - pos.index) > 0) {
1994                                     c = text.charAt(pos.index);
1995                                     if (c == '+') {
1996                                         sign = 1;
1997                                     } else if (c == '-') {
1998                                         sign = -1;
1999                                     }
2000                                 }
2001 
2002                                 if (sign == 0) {    /* "GMT" without offset */
2003                                     calb.set(Calendar.ZONE_OFFSET, 0)
2004                                         .set(Calendar.DST_OFFSET, 0);
2005                                     return pos.index;
2006                                 }
2007 
2008                                 // Parse the rest as "hh:mm"
2009                                 int i = subParseNumericZone(text, ++pos.index,
2010                                                             sign, 0, true, calb);
2011                                 if (i > 0) {
2012                                     return i;
2013                                 }
2014                                 pos.index = -i;
2015                             } else {
2016                                 // Try parsing the text as a time zone
2017                                 // name or abbreviation.
2018                                 int i = subParseZoneString(text, pos.index, calb);
2019                                 if (i > 0) {
2020                                     return i;
2021                                 }
2022                                 pos.index = -i;
2023                             }
2024                         } else {
2025                             // Parse the rest as "hhmm" (RFC 822)
2026                             int i = subParseNumericZone(text, ++pos.index,
2027                                                         sign, 0, false, calb);
2028                             if (i > 0) {
2029                                 return i;
2030                             }
2031                             pos.index = -i;
2032                         }
2033                     } catch (IndexOutOfBoundsException e) {
2034                     }
2035                 }
2036                 break parsing;
2037 
2038             case PATTERN_ISO_ZONE:   // 'X'
2039                 {
2040                     if ((text.length() - pos.index) <= 0) {
2041                         break parsing;
2042                     }
2043 
2044                     int sign = 0;
2045                     char c = text.charAt(pos.index);
2046                     if (c == 'Z') {
2047                         calb.set(Calendar.ZONE_OFFSET, 0).set(Calendar.DST_OFFSET, 0);
2048                         return ++pos.index;
2049                     }
2050 
2051                     // parse text as "+/-hh[[:]mm]" based on count
2052                     if (c == '+') {
2053                         sign = 1;
2054                     } else if (c == '-') {
2055                         sign = -1;
2056                     } else {
2057                         ++pos.index;
2058                         break parsing;
2059                     }
2060                     int i = subParseNumericZone(text, ++pos.index, sign, count,
2061                                                 count == 3, calb);
2062                     if (i > 0) {
2063                         return i;
2064                     }
2065                     pos.index = -i;
2066                 }
2067                 break parsing;
2068 
2069             default:
2070          // case PATTERN_DAY_OF_MONTH:         // 'd'
2071          // case PATTERN_HOUR_OF_DAY0:         // 'H' 0-based.  eg, 23:59 + 1 hour =>> 00:59
2072          // case PATTERN_MINUTE:               // 'm'
2073          // case PATTERN_SECOND:               // 's'
2074          // case PATTERN_MILLISECOND:          // 'S'
2075          // case PATTERN_DAY_OF_YEAR:          // 'D'
2076          // case PATTERN_DAY_OF_WEEK_IN_MONTH: // 'F'
2077          // case PATTERN_WEEK_OF_YEAR:         // 'w'
2078          // case PATTERN_WEEK_OF_MONTH:        // 'W'
2079          // case PATTERN_HOUR0:                // 'K' 0-based.  eg, 11PM + 1 hour =>> 0 AM
2080          // case PATTERN_ISO_DAY_OF_WEEK:      // 'u' (pseudo field);
2081 
2082                 // Handle "generic" fields
2083                 if (obeyCount) {
2084                     if ((start+count) > text.length()) {
2085                         break parsing;
2086                     }
2087                     number = numberFormat.parse(text.substring(0, start+count), pos);
2088                 } else {
2089                     number = numberFormat.parse(text, pos);
2090                 }
2091                 if (number != null) {
2092                     value = number.intValue();
2093 
2094                     if (useFollowingMinusSignAsDelimiter && (value < 0) &&
2095                         (((pos.index < text.length()) &&
2096                          (text.charAt(pos.index) != minusSign)) ||
2097                          ((pos.index == text.length()) &&
2098                           (text.charAt(pos.index-1) == minusSign)))) {
2099                         value = -value;
2100                         pos.index--;
2101                     }
2102 
2103                     calb.set(field, value);
2104                     return pos.index;
2105                 }
2106                 break parsing;
2107             }
2108         }
2109 
2110         // Parsing failed.
2111         origPos.errorIndex = pos.index;
2112         return -1;
2113     }
2114 
2115     private final String getCalendarName() {
2116         return calendar.getClass().getName();
2117     }
2118 
2119     private boolean useDateFormatSymbols() {
2120         if (useDateFormatSymbols) {
2121             return true;
2122         }
2123         return isGregorianCalendar() || locale == null;
2124     }
2125 
2126     private boolean isGregorianCalendar() {
2127         return "java.util.GregorianCalendar".equals(getCalendarName());
2128     }
2129 
2130     /**
2131      * Translates a pattern, mapping each character in the from string to the
2132      * corresponding character in the to string.
2133      *
2134      * @exception IllegalArgumentException if the given pattern is invalid
2135      */
2136     private String translatePattern(String pattern, String from, String to) {
2137         StringBuilder result = new StringBuilder();
2138         boolean inQuote = false;
2139         for (int i = 0; i < pattern.length(); ++i) {
2140             char c = pattern.charAt(i);
2141             if (inQuote) {
2142                 if (c == '\'')
2143                     inQuote = false;
2144             }
2145             else {
2146                 if (c == '\'')
2147                     inQuote = true;
2148                 else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
2149                     int ci = from.indexOf(c);
2150                     if (ci >= 0) {
2151                         // patternChars is longer than localPatternChars due
2152                         // to serialization compatibility. The pattern letters
2153                         // unsupported by localPatternChars pass through.
2154                         if (ci < to.length()) {
2155                             c = to.charAt(ci);
2156                         }
2157                     } else {
2158                         throw new IllegalArgumentException("Illegal pattern " +
2159                                                            " character '" +
2160                                                            c + "'");
2161                     }
2162                 }
2163             }
2164             result.append(c);
2165         }
2166         if (inQuote)
2167             throw new IllegalArgumentException("Unfinished quote in pattern");
2168         return result.toString();
2169     }
2170 
2171     /**
2172      * Returns a pattern string describing this date format.
2173      *
2174      * @return a pattern string describing this date format.
2175      */
2176     public String toPattern() {
2177         return pattern;
2178     }
2179 
2180     /**
2181      * Returns a localized pattern string describing this date format.
2182      *
2183      * @return a localized pattern string describing this date format.
2184      */
2185     public String toLocalizedPattern() {
2186         return translatePattern(pattern,
2187                                 DateFormatSymbols.patternChars,
2188                                 formatData.getLocalPatternChars());
2189     }
2190 
2191     /**
2192      * Applies the given pattern string to this date format.
2193      *
2194      * @param pattern the new date and time pattern for this date format
2195      * @exception NullPointerException if the given pattern is null
2196      * @exception IllegalArgumentException if the given pattern is invalid
2197      */
2198     public void applyPattern(String pattern)
2199     {
2200         compiledPattern = compile(pattern);
2201         this.pattern = pattern;
2202     }
2203 
2204     /**
2205      * Applies the given localized pattern string to this date format.
2206      *
2207      * @param pattern a String to be mapped to the new date and time format
2208      *        pattern for this format
2209      * @exception NullPointerException if the given pattern is null
2210      * @exception IllegalArgumentException if the given pattern is invalid
2211      */
2212     public void applyLocalizedPattern(String pattern) {
2213          String p = translatePattern(pattern,
2214                                      formatData.getLocalPatternChars(),
2215                                      DateFormatSymbols.patternChars);
2216          compiledPattern = compile(p);
2217          this.pattern = p;
2218     }
2219 
2220     /**
2221      * Gets a copy of the date and time format symbols of this date format.
2222      *
2223      * @return the date and time format symbols of this date format
2224      * @see #setDateFormatSymbols
2225      */
2226     public DateFormatSymbols getDateFormatSymbols()
2227     {
2228         return (DateFormatSymbols)formatData.clone();
2229     }
2230 
2231     /**
2232      * Sets the date and time format symbols of this date format.
2233      *
2234      * @param newFormatSymbols the new date and time format symbols
2235      * @exception NullPointerException if the given newFormatSymbols is null
2236      * @see #getDateFormatSymbols
2237      */
2238     public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
2239     {
2240         this.formatData = (DateFormatSymbols)newFormatSymbols.clone();
2241         useDateFormatSymbols = true;
2242     }
2243 
2244     /**
2245      * Creates a copy of this <code>SimpleDateFormat</code>. This also
2246      * clones the format's date format symbols.
2247      *
2248      * @return a clone of this <code>SimpleDateFormat</code>
2249      */
2250     public Object clone() {
2251         SimpleDateFormat other = (SimpleDateFormat) super.clone();
2252         other.formatData = (DateFormatSymbols) formatData.clone();
2253         return other;
2254     }
2255 
2256     /**
2257      * Returns the hash code value for this <code>SimpleDateFormat</code> object.
2258      *
2259      * @return the hash code value for this <code>SimpleDateFormat</code> object.
2260      */
2261     public int hashCode()
2262     {
2263         return pattern.hashCode();
2264         // just enough fields for a reasonable distribution
2265     }
2266 
2267     /**
2268      * Compares the given object with this <code>SimpleDateFormat</code> for
2269      * equality.
2270      *
2271      * @return true if the given object is equal to this
2272      * <code>SimpleDateFormat</code>
2273      */
2274     public boolean equals(Object obj)
2275     {
2276         if (!super.equals(obj)) return false; // super does class check
2277         SimpleDateFormat that = (SimpleDateFormat) obj;
2278         return (pattern.equals(that.pattern)
2279                 && formatData.equals(that.formatData));
2280     }
2281 
2282     /**
2283      * After reading an object from the input stream, the format
2284      * pattern in the object is verified.
2285      * <p>
2286      * @exception InvalidObjectException if the pattern is invalid
2287      */
2288     private void readObject(ObjectInputStream stream)
2289                          throws IOException, ClassNotFoundException {
2290         stream.defaultReadObject();
2291 
2292         try {
2293             compiledPattern = compile(pattern);
2294         } catch (Exception e) {
2295             throw new InvalidObjectException("invalid pattern");
2296         }
2297 
2298         if (serialVersionOnStream < 1) {
2299             // didn't have defaultCenturyStart field
2300             initializeDefaultCentury();
2301         }
2302         else {
2303             // fill in dependent transient field
2304             parseAmbiguousDatesAsAfter(defaultCenturyStart);
2305         }
2306         serialVersionOnStream = currentSerialVersion;
2307 
2308         // If the deserialized object has a SimpleTimeZone, try
2309         // to replace it with a ZoneInfo equivalent in order to
2310         // be compatible with the SimpleTimeZone-based
2311         // implementation as much as possible.
2312         TimeZone tz = getTimeZone();
2313         if (tz instanceof SimpleTimeZone) {
2314             String id = tz.getID();
2315             TimeZone zi = TimeZone.getTimeZone(id);
2316             if (zi != null && zi.hasSameRules(tz) && zi.getID().equals(id)) {
2317                 setTimeZone(zi);
2318             }
2319         }
2320     }
2321 
2322     /**
2323      * Analyze the negative subpattern of DecimalFormat and set/update values
2324      * as necessary.
2325      */
2326     private void checkNegativeNumberExpression() {
2327         if ((numberFormat instanceof DecimalFormat) &&
2328             !numberFormat.equals(originalNumberFormat)) {
2329             String numberPattern = ((DecimalFormat)numberFormat).toPattern();
2330             if (!numberPattern.equals(originalNumberPattern)) {
2331                 hasFollowingMinusSign = false;
2332 
2333                 int separatorIndex = numberPattern.indexOf(';');
2334                 // If the negative subpattern is not absent, we have to analayze
2335                 // it in order to check if it has a following minus sign.
2336                 if (separatorIndex > -1) {
2337                     int minusIndex = numberPattern.indexOf('-', separatorIndex);
2338                     if ((minusIndex > numberPattern.lastIndexOf('0')) &&
2339                         (minusIndex > numberPattern.lastIndexOf('#'))) {
2340                         hasFollowingMinusSign = true;
2341                         minusSign = ((DecimalFormat)numberFormat).getDecimalFormatSymbols().getMinusSign();
2342                     }
2343                 }
2344                 originalNumberPattern = numberPattern;
2345             }
2346             originalNumberFormat = numberFormat;
2347         }
2348     }
2349 
2350 }