/*

* Copyright (c) 1996, 2013, Oracle and/or its affiliates. All rights reserved.

* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

*

* This code is free software; you can redistribute it and/or modify it

* under the terms of the GNU General Public License version 2 only, as

* published by the Free Software Foundation. Oracle designates this

* particular file as subject to the "Classpath" exception as provided

* by Oracle in the LICENSE file that accompanied this code.

*

* This code is distributed in the hope that it will be useful, but WITHOUT

* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License

* version 2 for more details (a copy is included in the LICENSE file that

* accompanied this code).

*

* You should have received a copy of the GNU General Public License version

* 2 along with this work; if not, write to the Free Software Foundation,

* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

*

* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

* or visit www.oracle.com if you need additional information or have any

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/*

* (C) Copyright Taligent, Inc. 1996 - All Rights Reserved

* (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved

*

* The original version of this source code and documentation is copyrighted

* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These

* materials are provided under terms of a License Agreement between Taligent

* and Sun. This technology is protected by multiple US and International

* patents. This notice and attribution to Taligent may not be removed.

* Taligent is a registered trademark of Taligent, Inc.

*

*/

package java.text;

import java.io.IOException;

import java.io.InvalidObjectException;

import java.io.ObjectInputStream;

import static java.text.DateFormatSymbols.*;

import java.util.Calendar;

import java.util.Date;

import java.util.GregorianCalendar;

import java.util.Locale;

import java.util.Map;

import java.util.SimpleTimeZone;

import java.util.SortedMap;

import java.util.TimeZone;

import java.util.concurrent.ConcurrentHashMap;

import java.util.concurrent.ConcurrentMap;

import sun.util.calendar.CalendarUtils;

import sun.util.calendar.ZoneInfoFile;

import sun.util.locale.provider.LocaleProviderAdapter;

/**

* <code>SimpleDateFormat</code> is a concrete class for formatting and

* parsing dates in a locale-sensitive manner. It allows for formatting

* (date &rarr; text), parsing (text &rarr; date), and normalization.

*

* <p>

* <code>SimpleDateFormat</code> allows you to start by choosing

* any user-defined patterns for date-time formatting. However, you

* are encouraged to create a date-time formatter with either

* <code>getTimeInstance</code>, <code>getDateInstance</code>, or

* <code>getDateTimeInstance</code> in <code>DateFormat</code>. Each

* of these class methods can return a date/time formatter initialized

* with a default format pattern. You may modify the format pattern

* using the <code>applyPattern</code> methods as desired.

* For more information on using these methods, see

* {@link DateFormat}.

*

* <h3>Date and Time Patterns</h3>

* <p>

* Date and time formats are specified by <em>date and time pattern</em>

* strings.

* Within date and time pattern strings, unquoted letters from

* <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to

* <code>'z'</code> are interpreted as pattern letters representing the

* components of a date or time string.

* Text can be quoted using single quotes (<code>'</code>) to avoid

* interpretation.

* <code>"''"</code> represents a single quote.

* All other characters are not interpreted; they're simply copied into the

* output string during formatting or matched against the input string

* during parsing.

* <p>

* The following pattern letters are defined (all other characters from

* <code>'A'</code> to <code>'Z'</code> and from <code>'a'</code> to

* <code>'z'</code> are reserved):

* <blockquote>

* <table border=0 cellspacing=3 cellpadding=0 summary="Chart shows pattern letters, date/time component, presentation, and examples.">

* <tr style="background-color: rgb(204, 204, 255);">

* <th align=left>Letter

* <th align=left>Date or Time Component

* <th align=left>Presentation

* <th align=left>Examples

* <tr>

* <td><code>G</code>

* <td>Era designator

* <td><a href="#text">Text</a>

* <td><code>AD</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>y</code>

* <td>Year

* <td><a href="#year">Year</a>

* <td><code>1996</code>; <code>96</code>

* <tr>

* <td><code>Y</code>

* <td>Week year

* <td><a href="#year">Year</a>

* <td><code>2009</code>; <code>09</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>M</code>

* <td>Month in year (context sensitive)

* <td><a href="#month">Month</a>

* <td><code>July</code>; <code>Jul</code>; <code>07</code>

* <tr>

* <td><code>L</code>

* <td>Month in year (standalone form)

* <td><a href="#month">Month</a>

* <td><code>July</code>; <code>Jul</code>; <code>07</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>w</code>

* <td>Week in year

* <td><a href="#number">Number</a>

* <td><code>27</code>

* <tr>

* <td><code>W</code>

* <td>Week in month

* <td><a href="#number">Number</a>

* <td><code>2</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>D</code>

* <td>Day in year

* <td><a href="#number">Number</a>

* <td><code>189</code>

* <tr>

* <td><code>d</code>

* <td>Day in month

* <td><a href="#number">Number</a>

* <td><code>10</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>F</code>

* <td>Day of week in month

* <td><a href="#number">Number</a>

* <td><code>2</code>

* <tr>

* <td><code>E</code>

* <td>Day name in week

* <td><a href="#text">Text</a>

* <td><code>Tuesday</code>; <code>Tue</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>u</code>

* <td>Day number of week (1 = Monday, ..., 7 = Sunday)

* <td><a href="#number">Number</a>

* <td><code>1</code>

* <tr>

* <td><code>a</code>

* <td>Am/pm marker

* <td><a href="#text">Text</a>

* <td><code>PM</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>H</code>

* <td>Hour in day (0-23)

* <td><a href="#number">Number</a>

* <td><code>0</code>

* <tr>

* <td><code>k</code>

* <td>Hour in day (1-24)

* <td><a href="#number">Number</a>

* <td><code>24</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>K</code>

* <td>Hour in am/pm (0-11)

* <td><a href="#number">Number</a>

* <td><code>0</code>

* <tr>

* <td><code>h</code>

* <td>Hour in am/pm (1-12)

* <td><a href="#number">Number</a>

* <td><code>12</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>m</code>

* <td>Minute in hour

* <td><a href="#number">Number</a>

* <td><code>30</code>

* <tr>

* <td><code>s</code>

* <td>Second in minute

* <td><a href="#number">Number</a>

* <td><code>55</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>S</code>

* <td>Millisecond

* <td><a href="#number">Number</a>

* <td><code>978</code>

* <tr>

* <td><code>z</code>

* <td>Time zone

* <td><a href="#timezone">General time zone</a>

* <td><code>Pacific Standard Time</code>; <code>PST</code>; <code>GMT-08:00</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>Z</code>

* <td>Time zone

* <td><a href="#rfc822timezone">RFC 822 time zone</a>

* <td><code>-0800</code>

* <tr>

* <td><code>X</code>

* <td>Time zone

* <td><a href="#iso8601timezone">ISO 8601 time zone</a>

* <td><code>-08</code>; <code>-0800</code>; <code>-08:00</code>

* </table>

* </blockquote>

* Pattern letters are usually repeated, as their number determines the

* exact presentation:

* <ul>

* <li><strong><a name="text">Text:</a></strong>

* For formatting, if the number of pattern letters is 4 or more,

* the full form is used; otherwise a short or abbreviated form

* is used if available.

* For parsing, both forms are accepted, independent of the number

* of pattern letters.<br><br></li>

* <li><strong><a name="number">Number:</a></strong>

* For formatting, the number of pattern letters is the minimum

* number of digits, and shorter numbers are zero-padded to this amount.

* For parsing, the number of pattern letters is ignored unless

* it's needed to separate two adjacent fields.<br><br></li>

* <li><strong><a name="year">Year:</a></strong>

* If the formatter's {@link #getCalendar() Calendar} is the Gregorian

* calendar, the following rules are applied.<br>

* <ul>

* <li>For formatting, if the number of pattern letters is 2, the year

* is truncated to 2 digits; otherwise it is interpreted as a

* <a href="#number">number</a>.

* <li>For parsing, if the number of pattern letters is more than 2,

* the year is interpreted literally, regardless of the number of

* digits. So using the pattern "MM/dd/yyyy", "01/11/12" parses to

* Jan 11, 12 A.D.

* <li>For parsing with the abbreviated year pattern ("y" or "yy"),

* <code>SimpleDateFormat</code> must interpret the abbreviated year

* relative to some century. It does this by adjusting dates to be

* within 80 years before and 20 years after the time the <code>SimpleDateFormat</code>

* instance is created. For example, using a pattern of "MM/dd/yy" and a

* <code>SimpleDateFormat</code> instance created on Jan 1, 1997, the string

* "01/11/12" would be interpreted as Jan 11, 2012 while the string "05/04/64"

* would be interpreted as May 4, 1964.

* During parsing, only strings consisting of exactly two digits, as defined by

* {@link Character#isDigit(char)}, will be parsed into the default century.

* Any other numeric string, such as a one digit string, a three or more digit

* string, or a two digit string that isn't all digits (for example, "-1"), is

* interpreted literally. So "01/02/3" or "01/02/003" are parsed, using the

* same pattern, as Jan 2, 3 AD. Likewise, "01/02/-3" is parsed as Jan 2, 4 BC.

* </ul>

* Otherwise, calendar system specific forms are applied.

* For both formatting and parsing, if the number of pattern

* letters is 4 or more, a calendar specific {@linkplain

* Calendar#LONG long form} is used. Otherwise, a calendar

* specific {@linkplain Calendar#SHORT short or abbreviated form}

* is used.<br>

* <br>

* If week year {@code 'Y'} is specified and the {@linkplain

* #getCalendar() calendar} doesn't support any <a

* href="../util/GregorianCalendar.html#week_year"> week

* years</a>, the calendar year ({@code 'y'}) is used instead. The

* support of week years can be tested with a call to {@link

* DateFormat#getCalendar() getCalendar()}.{@link

* java.util.Calendar#isWeekDateSupported()

* isWeekDateSupported()}.<br><br></li>

* <li><strong><a name="month">Month:</a></strong>

* If the number of pattern letters is 3 or more, the month is

* interpreted as <a href="#text">text</a>; otherwise,

* it is interpreted as a <a href="#number">number</a>.<br>

* <ul>

* <li>Letter <em>M</em> produces context-sensitive month names, such as the

* embedded form of names. If a {@code DateFormatSymbols} has been set

* explicitly with constructor {@link #SimpleDateFormat(String,

* DateFormatSymbols)} or method {@link

* #setDateFormatSymbols(DateFormatSymbols)}, the month names given by

* the {@code DateFormatSymbols} are used.</li>

* <li>Letter <em>L</em> produces the standalone form of month names.</li>

* </ul>

* <br></li>

* <li><strong><a name="timezone">General time zone:</a></strong>

* Time zones are interpreted as <a href="#text">text</a> if they have

* names. For time zones representing a GMT offset value, the

* following syntax is used:

* <pre>

* <a name="GMTOffsetTimeZone"><i>GMTOffsetTimeZone:</i></a>

* <code>GMT</code> <i>Sign</i> <i>Hours</i> <code>:</code> <i>Minutes</i>

* <i>Sign:</i> one of

* <code>+ -</code>

* <i>Hours:</i>

* <i>Digit</i>

* <i>Digit</i> <i>Digit</i>

* <i>Minutes:</i>

* <i>Digit</i> <i>Digit</i>

* <i>Digit:</i> one of

* <code>0 1 2 3 4 5 6 7 8 9</code></pre>

* <i>Hours</i> must be between 0 and 23, and <i>Minutes</i> must be between

* 00 and 59. The format is locale independent and digits must be taken

* from the Basic Latin block of the Unicode standard.

* <p>For parsing, <a href="#rfc822timezone">RFC 822 time zones</a> are also

* accepted.<br><br></li>

* <li><strong><a name="rfc822timezone">RFC 822 time zone:</a></strong>

* For formatting, the RFC 822 4-digit time zone format is used:

*

* <pre>

* <i>RFC822TimeZone:</i>

* <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>

* <i>TwoDigitHours:</i>

* <i>Digit Digit</i></pre>

* <i>TwoDigitHours</i> must be between 00 and 23. Other definitions

* are as for <a href="#timezone">general time zones</a>.

*

* <p>For parsing, <a href="#timezone">general time zones</a> are also

* accepted.

* <li><strong><a name="iso8601timezone">ISO 8601 Time zone:</a></strong>

* The number of pattern letters designates the format for both formatting

* and parsing as follows:

* <pre>

* <i>ISO8601TimeZone:</i>

* <i>OneLetterISO8601TimeZone</i>

* <i>TwoLetterISO8601TimeZone</i>

* <i>ThreeLetterISO8601TimeZone</i>

* <i>OneLetterISO8601TimeZone:</i>

* <i>Sign</i> <i>TwoDigitHours</i>

* {@code Z}

* <i>TwoLetterISO8601TimeZone:</i>

* <i>Sign</i> <i>TwoDigitHours</i> <i>Minutes</i>

* {@code Z}

* <i>ThreeLetterISO8601TimeZone:</i>

* <i>Sign</i> <i>TwoDigitHours</i> {@code :} <i>Minutes</i>

* {@code Z}</pre>

* Other definitions are as for <a href="#timezone">general time zones</a> or

* <a href="#rfc822timezone">RFC 822 time zones</a>.

*

* <p>For formatting, if the offset value from GMT is 0, {@code "Z"} is

* produced. If the number of pattern letters is 1, any fraction of an hour

* is ignored. For example, if the pattern is {@code "X"} and the time zone is

* {@code "GMT+05:30"}, {@code "+05"} is produced.

*

* <p>For parsing, {@code "Z"} is parsed as the UTC time zone designator.

* <a href="#timezone">General time zones</a> are <em>not</em> accepted.

*

* <p>If the number of pattern letters is 4 or more, {@link

* IllegalArgumentException} is thrown when constructing a {@code

* SimpleDateFormat} or {@linkplain #applyPattern(String) applying a

* pattern}.

* </ul>

* <code>SimpleDateFormat</code> also supports <em>localized date and time

* pattern</em> strings. In these strings, the pattern letters described above

* may be replaced with other, locale dependent, pattern letters.

* <code>SimpleDateFormat</code> does not deal with the localization of text

* other than the pattern letters; that's up to the client of the class.

*

* <h4>Examples</h4>

*

* The following examples show how date and time patterns are interpreted in

* the U.S. locale. The given date and time are 2001-07-04 12:08:56 local time

* in the U.S. Pacific Time time zone.

* <blockquote>

* <table border=0 cellspacing=3 cellpadding=0 summary="Examples of date and time patterns interpreted in the U.S. locale">

* <tr style="background-color: rgb(204, 204, 255);">

* <th align=left>Date and Time Pattern

* <th align=left>Result

* <tr>

* <td><code>"yyyy.MM.dd G 'at' HH:mm:ss z"</code>

* <td><code>2001.07.04 AD at 12:08:56 PDT</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>"EEE, MMM d, ''yy"</code>

* <td><code>Wed, Jul 4, '01</code>

* <tr>

* <td><code>"h:mm a"</code>

* <td><code>12:08 PM</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>"hh 'o''clock' a, zzzz"</code>

* <td><code>12 o'clock PM, Pacific Daylight Time</code>

* <tr>

* <td><code>"K:mm a, z"</code>

* <td><code>0:08 PM, PDT</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>"yyyyy.MMMMM.dd GGG hh:mm aaa"</code>

* <td><code>02001.July.04 AD 12:08 PM</code>

* <tr>

* <td><code>"EEE, d MMM yyyy HH:mm:ss Z"</code>

* <td><code>Wed, 4 Jul 2001 12:08:56 -0700</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>"yyMMddHHmmssZ"</code>

* <td><code>010704120856-0700</code>

* <tr>

* <td><code>"yyyy-MM-dd'T'HH:mm:ss.SSSZ"</code>

* <td><code>2001-07-04T12:08:56.235-0700</code>

* <tr style="background-color: rgb(238, 238, 255);">

* <td><code>"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"</code>

* <td><code>2001-07-04T12:08:56.235-07:00</code>

* <tr>

* <td><code>"YYYY-'W'ww-u"</code>

* <td><code>2001-W27-3</code>

* </table>

* </blockquote>

*

* <h4><a name="synchronization">Synchronization</a></h4>

*

* <p>

* Date formats are not synchronized.

* It is recommended to create separate format instances for each thread.

* If multiple threads access a format concurrently, it must be synchronized

* externally.

*

* @see <a href="https://docs.oracle.com/javase/tutorial/i18n/format/simpleDateFormat.html">Java Tutorial</a>

* @see java.util.Calendar

* @see java.util.TimeZone

* @see DateFormat

* @see DateFormatSymbols

* @author Mark Davis, Chen-Lieh Huang, Alan Liu

*/

public class SimpleDateFormat extends DateFormat {

// the official serial version ID which says cryptically

// which version we're compatible with

static final long serialVersionUID = 4774881970558875024L;

// the internal serial version which says which version was written

// - 0 (default) for version up to JDK 1.1.3

// - 1 for version from JDK 1.1.4, which includes a new field

static final int currentSerialVersion = 1;

/**

* The version of the serialized data on the stream. Possible values:

* <ul>

* <li><b>0</b> or not present on stream: JDK 1.1.3. This version

* has no <code>defaultCenturyStart</code> on stream.

* <li><b>1</b> JDK 1.1.4 or later. This version adds

* <code>defaultCenturyStart</code>.

* </ul>

* When streaming out this class, the most recent format

* and the highest allowable <code>serialVersionOnStream</code>

* is written.

* @serial

* @since JDK1.1.4

*/

private int serialVersionOnStream = currentSerialVersion;

/**

* The pattern string of this formatter. This is always a non-localized

* pattern. May not be null. See class documentation for details.

* @serial

*/

private String pattern;

/**

* Saved numberFormat and pattern.

* @see SimpleDateFormat#checkNegativeNumberExpression

*/

transient private NumberFormat originalNumberFormat;

transient private String originalNumberPattern;

/**

* The minus sign to be used with format and parse.

*/

transient private char minusSign = '-';

/**

* True when a negative sign follows a number.

* (True as default in Arabic.)

*/

transient private boolean hasFollowingMinusSign = false;

/**

* True if standalone form needs to be used.

*/

transient private boolean forceStandaloneForm = false;

/**

* The compiled pattern.

*/

transient private char[] compiledPattern;

/**

* Tags for the compiled pattern.

*/

private final static int TAG_QUOTE_ASCII_CHAR = 100;

private final static int TAG_QUOTE_CHARS = 101;

/**

* Locale dependent digit zero.

* @see #zeroPaddingNumber

* @see java.text.DecimalFormatSymbols#getZeroDigit

*/

transient private char zeroDigit;

/**

* The symbols used by this formatter for week names, month names,

* etc. May not be null.

* @serial

* @see java.text.DateFormatSymbols

*/

private DateFormatSymbols formatData;

/**

* We map dates with two-digit years into the century starting at

* <code>defaultCenturyStart</code>, which may be any date. May

* not be null.

* @serial

* @since JDK1.1.4

*/

private Date defaultCenturyStart;

transient private int defaultCenturyStartYear;

private static final int MILLIS_PER_MINUTE = 60 * 1000;

// For time zones that have no names, use strings GMT+minutes and

// GMT-minutes. For instance, in France the time zone is GMT+60.

private static final String GMT = "GMT";

/**

* Cache NumberFormat instances with Locale key.

*/

private static final ConcurrentMap<Locale, NumberFormat> cachedNumberFormatData

= new ConcurrentHashMap<>(3);

/**

* The Locale used to instantiate this

* <code>SimpleDateFormat</code>. The value may be null if this object

* has been created by an older <code>SimpleDateFormat</code> and

* deserialized.

*

* @serial

* @since 1.6

*/

private Locale locale;

/**

* Indicates whether this <code>SimpleDateFormat</code> should use

* the DateFormatSymbols. If true, the format and parse methods

* use the DateFormatSymbols values. If false, the format and

* parse methods call Calendar.getDisplayName or

* Calendar.getDisplayNames.

*/

transient boolean useDateFormatSymbols;

/**

* Constructs a <code>SimpleDateFormat</code> using the default pattern and

* date format symbols for the default

* {@link java.util.Locale.Category#FORMAT FORMAT} locale.

* <b>Note:</b> This constructor may not support all locales.

* For full coverage, use the factory methods in the {@link DateFormat}

* class.

*/

public SimpleDateFormat() {

this("", Locale.getDefault(Locale.Category.FORMAT));

applyPatternImpl(LocaleProviderAdapter.getResourceBundleBased().getLocaleResources(locale)

.getDateTimePattern(SHORT, SHORT, calendar));

}

/**

* Constructs a <code>SimpleDateFormat</code> using the given pattern and

* the default date format symbols for the default

* {@link java.util.Locale.Category#FORMAT FORMAT} locale.

* <b>Note:</b> This constructor may not support all locales.

* For full coverage, use the factory methods in the {@link DateFormat}

* class.

* <p>This is equivalent to calling

* {@link #SimpleDateFormat(String, Locale)

* SimpleDateFormat(pattern, Locale.getDefault(Locale.Category.FORMAT))}.

*

* @see java.util.Locale#getDefault(java.util.Locale.Category)

* @see java.util.Locale.Category#FORMAT

* @param pattern the pattern describing the date and time format

* @exception NullPointerException if the given pattern is null

* @exception IllegalArgumentException if the given pattern is invalid

*/

public SimpleDateFormat(String pattern)

{

this(pattern, Locale.getDefault(Locale.Category.FORMAT));

}

/**

* Constructs a <code>SimpleDateFormat</code> using the given pattern and

* the default date format symbols for the given locale.

* <b>Note:</b> This constructor may not support all locales.

* For full coverage, use the factory methods in the {@link DateFormat}

* class.

*

* @param pattern the pattern describing the date and time format

* @param locale the locale whose date format symbols should be used

* @exception NullPointerException if the given pattern or locale is null

* @exception IllegalArgumentException if the given pattern is invalid

*/

public SimpleDateFormat(String pattern, Locale locale)

{

if (pattern == null || locale == null) {

throw new NullPointerException();

}

initializeCalendar(locale);

this.pattern = pattern;

this.formatData = DateFormatSymbols.getInstanceRef(locale);

this.locale = locale;

initialize(locale);

}

/**

* Constructs a <code>SimpleDateFormat</code> using the given pattern and

* date format symbols.

*

* @param pattern the pattern describing the date and time format

* @param formatSymbols the date format symbols to be used for formatting

* @exception NullPointerException if the given pattern or formatSymbols is null

* @exception IllegalArgumentException if the given pattern is invalid

*/

public SimpleDateFormat(String pattern, DateFormatSymbols formatSymbols)

{

if (pattern == null || formatSymbols == null) {

throw new NullPointerException();

}

this.pattern = pattern;

this.formatData = (DateFormatSymbols) formatSymbols.clone();

this.locale = Locale.getDefault(Locale.Category.FORMAT);

initializeCalendar(this.locale);

initialize(this.locale);

useDateFormatSymbols = true;

}

/* Initialize compiledPattern and numberFormat fields */

private void initialize(Locale loc) {

// Verify and compile the given pattern.

compiledPattern = compile(pattern);

/* try the cache first */

numberFormat = cachedNumberFormatData.get(loc);

if (numberFormat == null) { /* cache miss */

numberFormat = NumberFormat.getIntegerInstance(loc);

numberFormat.setGroupingUsed(false);

/* update cache */

cachedNumberFormatData.putIfAbsent(loc, numberFormat);

}

numberFormat = (NumberFormat) numberFormat.clone();

initializeDefaultCentury();

}

private void initializeCalendar(Locale loc) {

if (calendar == null) {

assert loc != null;

// The format object must be constructed using the symbols for this zone.

// However, the calendar should use the current default TimeZone.

// If this is not contained in the locale zone strings, then the zone

// will be formatted using generic GMT+/-H:MM nomenclature.

calendar = Calendar.getInstance(TimeZone.getDefault(), loc);

}

}

/**

* Returns the compiled form of the given pattern. The syntax of

* the compiled pattern is:

* <blockquote>

* CompiledPattern:

* EntryList

* EntryList:

* Entry

* EntryList Entry

* Entry:

* TagField

* TagField data

* TagField:

* Tag Length

* TaggedData

* Tag:

* pattern_char_index

* TAG_QUOTE_CHARS

* Length:

* short_length

* long_length

* TaggedData:

* TAG_QUOTE_ASCII_CHAR ascii_char

*

* </blockquote>

*

* where `short_length' is an 8-bit unsigned integer between 0 and

* 254. `long_length' is a sequence of an 8-bit integer 255 and a

* 32-bit signed integer value which is split into upper and lower

* 16-bit fields in two char's. `pattern_char_index' is an 8-bit

* integer between 0 and 18. `ascii_char' is an 7-bit ASCII

* character value. `data' depends on its Tag value.

* <p>

* If Length is short_length, Tag and short_length are packed in a

* single char, as illustrated below.

* <blockquote>

* char[0] = (Tag << 8) | short_length;

* </blockquote>

*

* If Length is long_length, Tag and 255 are packed in the first

* char and a 32-bit integer, as illustrated below.

* <blockquote>

* char[0] = (Tag << 8) | 255;

* char[1] = (char) (long_length >>> 16);

* char[2] = (char) (long_length & 0xffff);

* </blockquote>

* <p>

* If Tag is a pattern_char_index, its Length is the number of

* pattern characters. For example, if the given pattern is

* "yyyy", Tag is 1 and Length is 4, followed by no data.

* <p>

* If Tag is TAG_QUOTE_CHARS, its Length is the number of char's

* following the TagField. For example, if the given pattern is

* "'o''clock'", Length is 7 followed by a char sequence of

* <code>o&nbs;'&nbs;c&nbs;l&nbs;o&nbs;c&nbs;k</code>.

* <p>

* TAG_QUOTE_ASCII_CHAR is a special tag and has an ASCII

* character in place of Length. For example, if the given pattern

* is "'o'", the TaggedData entry is

* <code>((TAG_QUOTE_ASCII_CHAR&nbs;<<&nbs;8)&nbs;|&nbs;'o')</code>.

*

* @exception NullPointerException if the given pattern is null

* @exception IllegalArgumentException if the given pattern is invalid

*/

private char[] compile(String pattern) {

int length = pattern.length();

boolean inQuote = false;

StringBuilder compiledCode = new StringBuilder(length * 2);

StringBuilder tmpBuffer = null;

int count = 0, tagcount = 0;

int lastTag = -1, prevTag = -1;

for (int i = 0; i < length; i++) {

char c = pattern.charAt(i);

if (c == '\'') {

// '' is treated as a single quote regardless of being

// in a quoted section.

if ((i + 1) < length) {

c = pattern.charAt(i + 1);

if (c == '\'') {

i++;

if (count != 0) {

encode(lastTag, count, compiledCode);

tagcount++;

prevTag = lastTag;

lastTag = -1;

count = 0;

}

if (inQuote) {

tmpBuffer.append(c);

} else {

compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));

}

continue;

}

}

if (!inQuote) {

if (count != 0) {

encode(lastTag, count, compiledCode);

tagcount++;

prevTag = lastTag;

lastTag = -1;

count = 0;

}

if (tmpBuffer == null) {

tmpBuffer = new StringBuilder(length);

} else {

tmpBuffer.setLength(0);

}

inQuote = true;

} else {

int len = tmpBuffer.length();

if (len == 1) {

char ch = tmpBuffer.charAt(0);

if (ch < 128) {

compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | ch));

} else {

compiledCode.append((char)(TAG_QUOTE_CHARS << 8 | 1));

compiledCode.append(ch);

}

} else {

encode(TAG_QUOTE_CHARS, len, compiledCode);

compiledCode.append(tmpBuffer);

}

inQuote = false;

}

continue;

}

if (inQuote) {

tmpBuffer.append(c);

continue;

}

if (!(c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z')) {

if (count != 0) {

encode(lastTag, count, compiledCode);

tagcount++;

prevTag = lastTag;

lastTag = -1;

count = 0;

}

if (c < 128) {

// In most cases, c would be a delimiter, such as ':'.

compiledCode.append((char)(TAG_QUOTE_ASCII_CHAR << 8 | c));

} else {

// Take any contiguous non-ASCII alphabet characters and

// put them in a single TAG_QUOTE_CHARS.

int j;

for (j = i + 1; j < length; j++) {

char d = pattern.charAt(j);

if (d == '\'' || (d >= 'a' && d <= 'z' || d >= 'A' && d <= 'Z')) {

break;

}

}

compiledCode.append((char)(TAG_QUOTE_CHARS << 8 | (j - i)));

for (; i < j; i++) {

compiledCode.append(pattern.charAt(i));

}

i--;

}

continue;

}

int tag;

if ((tag = DateFormatSymbols.patternChars.indexOf(c)) == -1) {

throw new IllegalArgumentException("Illegal pattern character " +

"'" + c + "'");

}

if (lastTag == -1 || lastTag == tag) {

lastTag = tag;

count++;

continue;

}

encode(lastTag, count, compiledCode);

tagcount++;

prevTag = lastTag;

lastTag = tag;

count = 1;

}

if (inQuote) {

throw new IllegalArgumentException("Unterminated quote");

}

if (count != 0) {

encode(lastTag, count, compiledCode);

tagcount++;

prevTag = lastTag;

}

forceStandaloneForm = (tagcount == 1 && prevTag == PATTERN_MONTH);

// Copy the compiled pattern to a char array

int len = compiledCode.length();

char[] r = new char[len];

compiledCode.getChars(0, len, r, 0);

return r;

}

/**

* Encodes the given tag and length and puts encoded char(s) into buffer.

*/

private static void encode(int tag, int length, StringBuilder buffer) {

if (tag == PATTERN_ISO_ZONE && length >= 4) {

throw new IllegalArgumentException("invalid ISO 8601 format: length=" + length);

}

if (length < 255) {

buffer.append((char)(tag << 8 | length));

} else {

buffer.append((char)((tag << 8) | 0xff));

buffer.append((char)(length >>> 16));

buffer.append((char)(length & 0xffff));

}

}

/* Initialize the fields we use to disambiguate ambiguous years. Separate

* so we can call it from readObject().

*/

private void initializeDefaultCentury() {

calendar.setTimeInMillis(System.currentTimeMillis());

calendar.add( Calendar.YEAR, -80 );

parseAmbiguousDatesAsAfter(calendar.getTime());

}

/* Define one-century window into which to disambiguate dates using

* two-digit years.

*/

private void parseAmbiguousDatesAsAfter(Date startDate) {

defaultCenturyStart = startDate;

calendar.setTime(startDate);

defaultCenturyStartYear = calendar.get(Calendar.YEAR);

}

/**

* Sets the 100-year period 2-digit years will be interpreted as being in

* to begin on the date the user specifies.

*

* @param startDate During parsing, two digit years will be placed in the range

* <code>startDate</code> to <code>startDate + 100 years</code>.

* @see #get2DigitYearStart

* @since 1.2

*/

public void set2DigitYearStart(Date startDate) {

parseAmbiguousDatesAsAfter(new Date(startDate.getTime()));

}

/**

* Returns the beginning date of the 100-year period 2-digit years are interpreted

* as being within.

*

* @return the start of the 100-year period into which two digit years are

* parsed

* @see #set2DigitYearStart

* @since 1.2

*/

public Date get2DigitYearStart() {

return (Date) defaultCenturyStart.clone();

}

/**

* Formats the given <code>Date</code> into a date/time string and appends

* the result to the given <code>StringBuffer</code>.

*

* @param date the date-time value to be formatted into a date-time string.

* @param toAppendTo where the new date-time text is to be appended.

* @param pos the formatting position. On input: an alignment field,

* if desired. On output: the offsets of the alignment field.

* @return the formatted date-time string.

* @exception NullPointerException if the given {@code date} is {@code null}.

*/

@Override

public StringBuffer format(Date date, StringBuffer toAppendTo,

FieldPosition pos)

{

pos.beginIndex = pos.endIndex = 0;

return format(date, toAppendTo, pos.getFieldDelegate());

}

// Called from Format after creating a FieldDelegate

private StringBuffer format(Date date, StringBuffer toAppendTo,

FieldDelegate delegate) {

// Convert input date to time field list

calendar.setTime(date);

boolean useDateFormatSymbols = useDateFormatSymbols();

for (int i = 0; i < compiledPattern.length; ) {

int tag = compiledPattern[i] >>> 8;

int count = compiledPattern[i++] & 0xff;

if (count == 255) {

count = compiledPattern[i++] << 16;

count |= compiledPattern[i++];

}

switch (tag) {

case TAG_QUOTE_ASCII_CHAR:

toAppendTo.append((char)count);

break;

case TAG_QUOTE_CHARS:

toAppendTo.append(compiledPattern, i, count);

i += count;

break;

default:

subFormat(tag, count, delegate, toAppendTo, useDateFormatSymbols);

break;

}

}

return toAppendTo;

}

/**

* Formats an Object producing an <code>AttributedCharacterIterator</code>.

* You can use the returned <code>AttributedCharacterIterator</code>

* to build the resulting String, as well as to determine information

* about the resulting String.

* <p>

* Each attribute key of the AttributedCharacterIterator will be of type

* <code>DateFormat.Field</code>, with the corresponding attribute value

* being the same as the attribute key.

*

* @exception NullPointerException if obj is null.

* @exception IllegalArgumentException if the Format cannot format the

* given object, or if the Format's pattern string is invalid.

* @param obj The object to format

* @return AttributedCharacterIterator describing the formatted value.

* @since 1.4

*/

@Override

public AttributedCharacterIterator formatToCharacterIterator(Object obj) {

StringBuffer sb = new StringBuffer();

CharacterIteratorFieldDelegate delegate = new

CharacterIteratorFieldDelegate();

if (obj instanceof Date) {

format((Date)obj, sb, delegate);

}

else if (obj instanceof Number) {

format(new Date(((Number)obj).longValue()), sb, delegate);