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/*
* @(#)SimpleDateFormat.java 1.31 98/08/27
*
* (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
* (C) Copyright IBM Corp. 1996 - All Rights Reserved
*
* Portions copyright (c) 1996 Sun Microsystems, Inc. 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.
*
* Permission to use, copy, modify, and distribute this software
* and its documentation for NON-COMMERCIAL purposes and without
* fee is hereby granted provided that this copyright notice
* appears in all copies. Please refer to the file "copyright.html"
* for further important copyright and licensing information.
*
* SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
* THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
* ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
* DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*
*/
package java.text;
import java.util.TimeZone;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import java.util.ResourceBundle;
import java.util.SimpleTimeZone;
import java.util.GregorianCalendar;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.lang.ClassNotFoundException;
import java.util.Hashtable;
/**
* <code>SimpleDateFormat</code> is a concrete class for formatting and
* parsing dates in a locale-sensitive manner. It allows for formatting
* (date -> text), parsing (text -> 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
* <a href="java.text.DateFormat.html"><code>DateFormat</code></a>.
*
* <p>
* <strong>Time Format Syntax:</strong>
* <p>
* To specify the time format use a <em>time pattern</em> string.
* In this pattern, all ASCII letters are reserved as pattern letters,
* which are defined as the following:
* <blockquote>
* <pre>
* Symbol Meaning Presentation Example
* ------ ------- ------------ -------
* G era designator (Text) AD
* y year (Number) 1996
* M month in year (Text & Number) July & 07
* d day in month (Number) 10
* h hour in am/pm (1~12) (Number) 12
* H hour in day (0~23) (Number) 0
* m minute in hour (Number) 30
* s second in minute (Number) 55
* S millisecond (Number) 978
* E day in week (Text) Tuesday
* D day in year (Number) 189
* F day of week in month (Number) 2 (2nd Wed in July)
* w week in year (Number) 27
* W week in month (Number) 2
* a am/pm marker (Text) PM
* k hour in day (1~24) (Number) 24
* K hour in am/pm (0~11) (Number) 0
* z time zone (Text) Pacific Standard Time
* ' escape for text (Delimiter)
* '' single quote (Literal) '
* </pre>
* </blockquote>
* The count of pattern letters determine the format.
* <p>
* <strong>(Text)</strong>: 4 or more pattern letters--use full form,
* < 4--use short or abbreviated form if one exists.
* <p>
* <strong>(Number)</strong>: the minimum number of digits. Shorter
* numbers are zero-padded to this amount. Year is handled specially;
* that is, if the count of 'y' is 2, the Year will be truncated to 2 digits.
* <p>
* <strong>(Text & Number)</strong>: 3 or over, use text, otherwise use number.
* <p>
* Any characters in the pattern that are not in the ranges of ['a'..'z']
* and ['A'..'Z'] will be treated as quoted text. For instance, characters
* like ':', '.', ' ', '#' and '@' will appear in the resulting time text
* even they are not embraced within single quotes.
* <p>
* A pattern containing any invalid pattern letter will result in a thrown
* exception during formatting or parsing.
*
* <p>
* <strong>Examples Using the US Locale:</strong>
* <blockquote>
* <pre>
* Format Pattern Result
* -------------- -------
* "yyyy.MM.dd G 'at' hh:mm:ss z" ->> 1996.07.10 AD at 15:08:56 PDT
* "EEE, MMM d, ''yy" ->> Wed, July 10, '96
* "h:mm a" ->> 12:08 PM
* "hh 'o''clock' a, zzzz" ->> 12 o'clock PM, Pacific Daylight Time
* "K:mm a, z" ->> 0:00 PM, PST
* "yyyyy.MMMMM.dd GGG hh:mm aaa" ->> 1996.July.10 AD 12:08 PM
* </pre>
* </blockquote>
* <strong>Code Sample:</strong>
* <pre>
* <blockquote>
* SimpleTimeZone pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, "PST");
* pdt.setStartRule(DateFields.APRIL, 1, DateFields.SUNDAY, 2*60*60*1000);
* pdt.setEndRule(DateFields.OCTOBER, -1, DateFields.SUNDAY, 2*60*60*1000);
*
* // Format the current time.
* SimpleDateFormat formatter
* = new SimpleDateFormat ("yyyy.mm.dd e 'at' hh:mm:ss a zzz");
* Date currentTime_1 = new Date();
* String dateString = formatter.format(currentTime_1);
*
* // Parse the previous string back into a Date.
* ParsePosition pos = new ParsePosition(0);
* Date currentTime_2 = formatter.parse(dateString, pos);
* </pre>
* </blockquote>
* In the example, the time value <code>currentTime_2</code> obtained from
* parsing will be equal to <code>currentTime_1</code>. However, they may not be
* equal if the am/pm marker 'a' is left out from the format pattern while
* the "hour in am/pm" pattern symbol is used. This information loss can
* happen when formatting the time in PM.
*
* <p>
* When parsing a date string using the abbreviated year pattern,
* SimpleDateFormat 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 SimpleDateFormat
* instance is created. For example, using a pattern of MM/dd/yy and a
* SimpleDateFormat 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.
*
* <p>
* For time zones that have no names, use strings GMT+hours:minutes or
* GMT-hours:minutes.
*
* <p>
* The calendar defines what is the first day of the week, the first week
* of the year, whether hours are zero based or not (0 vs 12 or 24), and the
* time zone. There is one common decimal format to handle all the numbers;
* the digit count is handled programmatically according to the pattern.
*
* @see java.util.Calendar
* @see java.util.GregorianCalendar
* @see java.util.TimeZone
* @see DateFormat
* @see DateFormatSymbols
* @see DecimalFormat
* @version 1.31 08/27/98
* @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;
private int serialVersionOnStream = currentSerialVersion;
private String pattern;
private DateFormatSymbols formatData;
// if dates have ambiguous years, we map them into the century starting
// at defaultCenturyStart, which may be any date.
private Date defaultCenturyStart; // field new in JDK 1.1.4
transient private int defaultCenturyStartYear;
private static final int millisPerHour = 60 * 60 * 1000;
private static final int millisPerMinute = 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_PLUS = "GMT+";
private static final String GMT_MINUS = "GMT-";
private static final String GMT = "GMT";
/**
* Cache to hold the DateTimePatterns of a Locale.
*/
private static final Hashtable cachedLocaleData = new Hashtable(3);
/**
* Construct a SimpleDateFormat using the default pattern for the default
* locale. <b>Note:</b> Not all locales support SimpleDateFormat; for full
* generality, use the factory methods in the DateFormat class.
*
* @see java.text.DateFormat
*/
public SimpleDateFormat() {
this(SHORT, SHORT + 4, Locale.getDefault());
}
/**
* Construct a SimpleDateFormat using the given pattern in the default
* locale. <b>Note:</b> Not all locales support SimpleDateFormat; for full
* generality, use the factory methods in the DateFormat class.
*/
public SimpleDateFormat(String pattern)
{
this(pattern, Locale.getDefault());
}
/**
* Construct a SimpleDateFormat using the given pattern and locale.
* <b>Note:</b> Not all locales support SimpleDateFormat; for full
* generality, use the factory methods in the DateFormat class.
*/
public SimpleDateFormat(String pattern, Locale loc)
{
this.pattern = pattern;
this.formatData = new DateFormatSymbols(loc);
initialize(loc);
}
/**
* Construct a SimpleDateFormat using the given pattern and
* locale-specific symbol data.
*/
public SimpleDateFormat(String pattern, DateFormatSymbols formatData)
{
this.pattern = pattern;
this.formatData = (DateFormatSymbols) formatData.clone();
initialize(Locale.getDefault());
}
/* Package-private, called by DateFormat factory methods */
SimpleDateFormat(int timeStyle, int dateStyle, Locale loc) {
/* try the cache first */
String[] dateTimePatterns = (String[]) cachedLocaleData.get(loc);
if (dateTimePatterns == null) { /* cache miss */
ResourceBundle r = ResourceBundle.getBundle
("java.text.resources.LocaleElements", loc);
dateTimePatterns = r.getStringArray("DateTimePatterns");
/* update cache */
cachedLocaleData.put(loc, dateTimePatterns);
}
formatData = new DateFormatSymbols(loc);
if ((timeStyle >= 0) && (dateStyle >= 0)) {
Object[] dateTimeArgs = {dateTimePatterns[timeStyle],
dateTimePatterns[dateStyle]};
pattern = MessageFormat.format(dateTimePatterns[8], dateTimeArgs);
}
else if (timeStyle >= 0)
pattern = dateTimePatterns[timeStyle];
else if (dateStyle >= 0)
pattern = dateTimePatterns[dateStyle];
else
throw new IllegalArgumentException("No date or time style specified");
initialize(loc);
}
/* Initialize calendar and numberFormat fields */
private void initialize(Locale loc) {
// 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);
numberFormat = NumberFormat.getInstance(loc);
numberFormat.setGroupingUsed(false);
if (numberFormat instanceof DecimalFormat)
((DecimalFormat)numberFormat).setDecimalSeparatorAlwaysShown(false);
numberFormat.setParseIntegerOnly(true); /* So that dd.mm.yy can be parsed */
numberFormat.setMinimumFractionDigits(0); // To prevent "Jan 1.00, 1997.00"
initializeDefaultCentury();
}
/* Initialize the fields we use to disambiguate ambiguous years. Separate
* so we can call it from readObject().
*/
private void initializeDefaultCentury() {
calendar.setTime( new Date() );
calendar.add( Calendar.YEAR, -80 );
parseAmbiguousDatesAsAfter(calendar.getTime());
}
/* Define one-century window into which to disambiguate dates using
* two-digit years. Make public in JDK 1.2.
*/
private void parseAmbiguousDatesAsAfter(Date startDate) {
defaultCenturyStart = startDate;
calendar.setTime(startDate);
defaultCenturyStartYear = calendar.get(Calendar.YEAR);
}
/**
* Overrides DateFormat
* <p>Formats a date or time, which is the standard millis
* since January 1, 1970, 00:00:00 GMT.
* <p>Example: using the US locale:
* "yyyy.MM.dd e 'at' HH:mm:ss zzz" ->> 1996.07.10 AD at 15:08:56 PDT
* @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.
* @see java.util.DateFormat
*/
public StringBuffer format(Date date, StringBuffer toAppendTo,
FieldPosition pos)
{
// Initialize
pos.beginIndex = pos.endIndex = 0;
// Convert input date to time field list
calendar.setTime(date);
boolean inQuote = false; // inQuote set true when hits 1st single quote
char prevCh = 0;
int count = 0; // number of time pattern characters repeated
int interQuoteCount = 1; // Number of characters between quotes
for (int i=0; i<pattern.length(); ++i)
{
char ch = pattern.charAt(i);
if (inQuote)
{
if (ch == '\'')
{
// ends with 2nd single quote
inQuote = false;
if (count == 0)
toAppendTo.append(ch); // two consecutive quotes outside a quote: ''
else count = 0;
interQuoteCount = 0;
}
else
{
toAppendTo.append(ch);
count++;
}
}
else // !inQuote
{
if (ch == '\'')
{
inQuote = true;
if (count > 0) // handle cases like: yyyy'....
{
toAppendTo.append(subFormat(prevCh, count,
toAppendTo.length(),
pos));
count = 0;
prevCh = 0;
}
// We count characters between quotes so we can recognize
// two single quotes inside a quote. Example: 'o''clock'.
if (interQuoteCount == 0)
{
toAppendTo.append(ch);
count = 1; // Make it look like we never left.
}
}
else if (ch >= 'a' && ch <= 'z' || ch >= 'A' && ch <= 'Z')
{
// ch is a date-time pattern
if (ch != prevCh && count > 0) //handle cases: eg, yyyyMMdd
{
toAppendTo.append(subFormat(prevCh, count,
toAppendTo.length(),
pos));
prevCh = ch;
count = 1;
}
else
{
if (ch != prevCh)
prevCh = ch;
count++;
}
}
else if (count > 0) // handle cases like: MM-dd-yy or HH:mm:ss
{
toAppendTo.append(subFormat(prevCh, count,
toAppendTo.length(),
pos));
toAppendTo.append(ch);
prevCh = 0;
count = 0;
}
else // any other unquoted characters
toAppendTo.append(ch);
++interQuoteCount;
}
}
// Format the last item in the pattern
if (count > 0)
{
toAppendTo.append(subFormat(prevCh, count,
toAppendTo.length(), pos));
}
return toAppendTo;
}
// Map index into pattern character string to Calendar field number
private static final int[] PATTERN_INDEX_TO_CALENDAR_FIELD =
{
Calendar.ERA, Calendar.YEAR, Calendar.MONTH, Calendar.DATE,
Calendar.HOUR_OF_DAY, Calendar.HOUR_OF_DAY, Calendar.MINUTE,
Calendar.SECOND, Calendar.MILLISECOND, Calendar.DAY_OF_WEEK,
Calendar.DAY_OF_YEAR, Calendar.DAY_OF_WEEK_IN_MONTH,
Calendar.WEEK_OF_YEAR, Calendar.WEEK_OF_MONTH,
Calendar.AM_PM, Calendar.HOUR, Calendar.HOUR, Calendar.ZONE_OFFSET
};
// Map index into pattern character string to DateFormat field number
private static final int[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD = {
DateFormat.ERA_FIELD, DateFormat.YEAR_FIELD, DateFormat.MONTH_FIELD,
DateFormat.DATE_FIELD, DateFormat.HOUR_OF_DAY1_FIELD,
DateFormat.HOUR_OF_DAY0_FIELD, DateFormat.MINUTE_FIELD,
DateFormat.SECOND_FIELD, DateFormat.MILLISECOND_FIELD,
DateFormat.DAY_OF_WEEK_FIELD, DateFormat.DAY_OF_YEAR_FIELD,
DateFormat.DAY_OF_WEEK_IN_MONTH_FIELD, DateFormat.WEEK_OF_YEAR_FIELD,
DateFormat.WEEK_OF_MONTH_FIELD, DateFormat.AM_PM_FIELD,
DateFormat.HOUR1_FIELD, DateFormat.HOUR0_FIELD,
DateFormat.TIMEZONE_FIELD,
};
// Private member function that does the real date/time formatting.
private String subFormat(char ch, int count, int beginOffset,
FieldPosition pos)
throws IllegalArgumentException
{
int patternCharIndex = -1;
int maxIntCount = 10;
String current = "";
if ((patternCharIndex=formatData.patternChars.indexOf(ch)) == -1)
throw new IllegalArgumentException("Illegal pattern character " +
"'" + ch + "'");
int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
int value = calendar.get(field);
switch (patternCharIndex) {
case 0: // 'G' - ERA
current = formatData.eras[value];
break;
case 1: // 'y' - YEAR
if (count >= 4)
// current = zeroPaddingNumber(value, 4, count);
current = zeroPaddingNumber(value, 4, maxIntCount);
else // count < 4
current = zeroPaddingNumber(value, 2, 2); // clip 1996 to 96
break;
case 2: // 'M' - MONTH
if (count >= 4)
current = formatData.months[value];
else if (count == 3)
current = formatData.shortMonths[value];
else
current = zeroPaddingNumber(value+1, count, maxIntCount);
break;
case 4: // 'k' - HOUR_OF_DAY: 1-based. eg, 23:59 + 1 hour =>> 24:59
if (value == 0)
current = zeroPaddingNumber(
calendar.getMaximum(Calendar.HOUR_OF_DAY)+1,
count, maxIntCount);
else
current = zeroPaddingNumber(value, count, maxIntCount);
break;
case 8: // 'S' - MILLISECOND
if (count > 3)
count = 3;
else if (count == 2)
value = value / 10;
else if (count == 1)
value = value / 100;
current = zeroPaddingNumber(value, count, maxIntCount);
break;
case 9: // 'E' - DAY_OF_WEEK
if (count >= 4)
current = formatData.weekdays[value];
else // count < 4, use abbreviated form if exists
current = formatData.shortWeekdays[value];
break;
case 14: // 'a' - AM_PM
current = formatData.ampms[value];
break;
case 15: // 'h' - HOUR:1-based. eg, 11PM + 1 hour =>> 12 AM
if (value == 0)
current = zeroPaddingNumber(
calendar.getLeastMaximum(Calendar.HOUR)+1,
count, maxIntCount);
else
current = zeroPaddingNumber(value, count, maxIntCount);
break;
case 17: // 'z' - ZONE_OFFSET
int zoneIndex
= formatData.getZoneIndex (calendar.getTimeZone().getID());
if (zoneIndex == -1)
{
// For time zones that have no names, use strings
// GMT+hours:minutes and GMT-hours:minutes.
// For instance, France time zone uses GMT+01:00.
StringBuffer zoneString = new StringBuffer();
value = calendar.get(Calendar.ZONE_OFFSET) +
calendar.get(Calendar.DST_OFFSET);
if (value < 0)
{
zoneString.append(GMT_MINUS);
value = -value; // suppress the '-' sign for text display.
}
else
zoneString.append(GMT_PLUS);
zoneString.append(
zeroPaddingNumber((int)(value/millisPerHour), 2, 2));
zoneString.append(':');
zoneString.append(
zeroPaddingNumber(
(int)((value%millisPerHour)/millisPerMinute), 2, 2));
current = zoneString.toString();
}
else if (calendar.get(Calendar.DST_OFFSET) != 0)
{
if (count >= 4)
current = formatData.zoneStrings[zoneIndex][3];
else
// count < 4, use abbreviated form if exists
current = formatData.zoneStrings[zoneIndex][4];
}
else
{
if (count >= 4)
current = formatData.zoneStrings[zoneIndex][1];
else
current = formatData.zoneStrings[zoneIndex][2];
}
break;
default:
// case 3: // 'd' - DATE
// case 5: // 'H' - HOUR_OF_DAY:0-based. eg, 23:59 + 1 hour =>> 00:59
// case 6: // 'm' - MINUTE
// case 7: // 's' - SECOND
// case 10: // 'D' - DAY_OF_YEAR
// case 11: // 'F' - DAY_OF_WEEK_IN_MONTH
// case 12: // 'w' - WEEK_OF_YEAR
// case 13: // 'W' - WEEK_OF_MONTH
// case 16: // 'K' - HOUR: 0-based. eg, 11PM + 1 hour =>> 0 AM
current = zeroPaddingNumber(value, count, maxIntCount);
break;
} // switch (patternCharIndex)
if (pos.field == PATTERN_INDEX_TO_DATE_FORMAT_FIELD[patternCharIndex]) {
// set for the first occurence only.
if (pos.beginIndex == 0 && pos.endIndex == 0) {
pos.beginIndex = beginOffset;
pos.endIndex = beginOffset + current.length();
}
}
return current;
}
// Pad the shorter numbers up to maxCount digits.
private String zeroPaddingNumber(long value, int minDigits, int maxDigits)
{
numberFormat.setMinimumIntegerDigits(minDigits);
numberFormat.setMaximumIntegerDigits(maxDigits);
return numberFormat.format(value);
}
/**
* Overrides DateFormat
* @see java.util.DateFormat
*/
public Date parse(String text, ParsePosition pos)
{
int start = pos.index;
int oldStart = start;
boolean[] ambiguousYear = {false};
calendar.clear(); // Clears all the time fields
boolean inQuote = false; // inQuote set true when hits 1st single quote
char prevCh = 0;
int count = 0;
int interQuoteCount = 1; // Number of chars between quotes
for (int i=0; i<pattern.length(); ++i)
{
char ch = pattern.charAt(i);
if (inQuote)
{
if (ch == '\'')
{
// ends with 2nd single quote
inQuote = false;
// two consecutive quotes outside a quote means we have
// a quote literal we need to match.
if (count == 0)
{
if (ch != text.charAt(start))
{
pos.index = oldStart;
return null;
}
++start;
}
count = 0;
interQuoteCount = 0;
}
else
{
// pattern uses text following from 1st single quote.
if (ch != text.charAt(start)) {
// Check for cases like: 'at' in pattern vs "xt"
// in time text, where 'a' doesn't match with 'x'.
// If fail to match, return null.
pos.index = oldStart; // left unchanged
return null;
}
++count;
++start;
}
}
else // !inQuote
{
if (ch == '\'')
{
inQuote = true;
if (count > 0) // handle cases like: e'at'
{
start=subParse(text, start, prevCh, count,
false, ambiguousYear);
if ( start<0 ) {
pos.index = oldStart;
return null;
}
count = 0;
}
if (interQuoteCount == 0)
{
// This indicates two consecutive quotes inside a quote,
// for example, 'o''clock'. We need to parse this as
// representing a single quote within the quote.
if (ch != text.charAt(start))
{
pos.index = oldStart;
return null;
}
++start;
count = 1; // Make it look like we never left
}
}
else if (ch >= 'a' && ch <= 'z' || ch >= 'A' && ch <= 'Z')
{
// ch is a date-time pattern
if (ch != prevCh && count > 0) // e.g., yyyymmdd
{
// This is the only case where we pass in 'true' for
// obeyCount. That's because the next field directly
// abuts this one, so we have to use the count to know when
// to stop parsing. [LIU]
start = subParse(text, start, prevCh, count, true,
ambiguousYear);
if (start < 0) {
pos.index = oldStart;
return null;
}
prevCh = ch;
count = 1;
}
else
{
if (ch != prevCh)
prevCh = ch;
count++;
}
}
else if (count > 0)
{
// handle cases like: MM-dd-yy, HH:mm:ss, or yyyy MM dd,
// where ch = '-', ':', or ' ', repectively.
start=subParse(text, start, prevCh, count,
false, ambiguousYear);
if ( start < 0 ) {
pos.index = oldStart;
return null;
}
if (start >= text.length() || ch != text.charAt(start)) {
// handle cases like: 'MMMM dd' in pattern vs. "janx20"
// in time text, where ' ' doesn't match with 'x'.
pos.index = oldStart;
return null;
}
start++;
count = 0;
prevCh = 0;
}
else // any other unquoted characters
{
if (ch != text.charAt(start)) {
// handle cases like: 'MMMM dd' in pattern vs.
// "jan,,,20" in time text, where " " doesn't
// match with ",,,".
pos.index = oldStart;
return null;
}
start++;
}
++interQuoteCount;
}
}
// Parse the last item in the pattern
if (count > 0)
{
start=subParse(text, start, prevCh, count,
false, ambiguousYear);
if ( start < 0 ) {
pos.index = oldStart;
return null;
}
}
// At this point the fields of Calendar have been set. Calendar
// will fill in default values for missing fields when the time
// is computed.
pos.index = start;
// This part is a problem: When we call parsedDate.after, we compute the time.
// Take the date April 3 2004 at 2:30 am. When this is first set up, the year
// will be wrong if we're parsing a 2-digit year pattern. It will be 1904.
// April 3 1904 is a Sunday (unlike 2004) so it is the DST onset day. 2:30 am
// is therefore an "impossible" time, since the time goes from 1:59 to 3:00 am
// on that day. It is therefore parsed out to fields as 3:30 am. Then we
// add 100 years, and get April 3 2004 at 3:30 am. Note that April 3 2004 is
// a Saturday, so it can have a 2:30 am -- and it should. [LIU]
/*
Date parsedDate = calendar.getTime();
if( ambiguousYear[0] && !parsedDate.after(defaultCenturyStart) ) {
calendar.add(Calendar.YEAR, 100);
parsedDate = calendar.getTime();
}
*/
// Because of the above condition, save off the fields in case we need to readjust.
// The procedure we use here is not particularly efficient, but there is no other
// way to do this given the API restrictions present in Calendar. We minimize
// inefficiency by only performing this computation when it might apply, that is,
// when the two-digit year is equal to the start year, and thus might fall at the
// front or the back of the default century. This only works because we adjust
// the year correctly to start with in other cases -- see subParse().
Date parsedDate;
try {
if (ambiguousYear[0]) // If this is true then the two-digit year == the default start year
{
// We need a copy of the fields, and we need to avoid triggering a call to
// complete(), which will recalculate the fields. Since we can't access
// the fields[] array in Calendar, we clone the entire object. This will
// stop working if Calendar.clone() is ever rewritten to call complete().
Calendar savedCalendar = (Calendar)calendar.clone();
parsedDate = calendar.getTime();
if (parsedDate.before(defaultCenturyStart))
{
// We can't use add here because that does a complete() first.
savedCalendar.set(Calendar.YEAR, defaultCenturyStartYear + 100);
parsedDate = savedCalendar.getTime();
}
}
else parsedDate = calendar.getTime();
}
// An IllegalArgumentException will be thrown by Calendar.getTime()
// if any fields are out of range, e.g., MONTH == 17.
catch (IllegalArgumentException e) {
pos.index = oldStart;
return null;
}
return parsedDate;
}
/**
* Private code-size reduction function used by subParse.
* @param text the time text being parsed.
* @param start where to start parsing.
* @param field the date field being parsed.
* @param data the string array to parsed.
* @return the new start position if matching succeeded; a negative number
* indicating matching failure, otherwise.
*/
private int matchString(String text, int start, int field, String[] data)
{
int i = 0;
int count = data.length;
if (field == Calendar.DAY_OF_WEEK) i = 1;
// There may be multiple strings in the data[] array which begin with
// the same prefix (e.g., Cerven and Cervenec (June and July) in Czech).
// We keep track of the longest match, and return that. Note that this
// unfortunately requires us to test all array elements.
int bestMatchLength = 0, bestMatch = -1;
for (; i<count; ++i)
{
int length = data[i].length();
// Always compare if we have no match yet; otherwise only compare
// against potentially better matches (longer strings).
if (length > bestMatchLength &&
text.regionMatches(true, start, data[i], 0, length))
{
bestMatch = i;
bestMatchLength = length;
}
}
if (bestMatch >= 0)
{
calendar.set(field, bestMatch);
return start + bestMatchLength;
}
return -start;
}
/**
* Private member function that converts the parsed date strings into
* timeFields. Returns -start (for ParsePosition) if failed.
* @param text the time text to be parsed.
* @param start where to start parsing.
* @param ch the pattern character for the date field text to be parsed.
* @param count the count of a pattern character.
* @param obeyCount if true, then the next field directly abuts this one,
* and we should use the count to know when to stop parsing.
* @param ambiguousYear return parameter; upon return, if ambiguousYear[0]
* is true, then a two-digit year was parsed and may need to be readjusted.
* @return the new start position if matching succeeded; a negative number
* indicating matching failure, otherwise.
*/
private int subParse(String text, int start, char ch, int count,
boolean obeyCount, boolean[] ambiguousYear)
{
Number number;
int value = 0;
int i;
ParsePosition pos = new ParsePosition(0);
int patternCharIndex = -1;
if ((patternCharIndex=formatData.patternChars.indexOf(ch)) == -1)
return -start;
pos.index = start;
int field = PATTERN_INDEX_TO_CALENDAR_FIELD[patternCharIndex];
// If there are any spaces here, skip over them. If we hit the end
// of the string, then fail.
for (;;) {
if (pos.index >= text.length()) return -start;
char c = text.charAt(pos.index);
if (c != ' ' && c != '\t') break;
++pos.index;
}
// We handle a few special cases here where we need to parse
// a number value. We handle further, more generic cases below. We need
// to handle some of them here because some fields require extra processing on
// the parsed value.
if (patternCharIndex == 4 /*HOUR_OF_DAY1_FIELD*/ ||
patternCharIndex == 15 /*HOUR1_FIELD*/ ||
(patternCharIndex == 2 /*MONTH_FIELD*/ && count <= 2) ||
patternCharIndex == 1 /*YEAR*/)
{
// It would be good to unify this with the obeyCount logic below,
// but that's going to be difficult.
if (obeyCount)
{
if ((start+count) > text.length()) return -start;
number = numberFormat.parse(text.substring(0, start+count), pos);
}
else number = numberFormat.parse(text, pos);
if (number == null) return -start;
value = number.intValue();
}
switch (patternCharIndex)
{
case 0: // 'G' - ERA
return matchString(text, start, Calendar.ERA, formatData.eras);
case 1: // 'y' - YEAR
// If there are 4 or more YEAR pattern characters, this indicates
// that the year value is to be treated literally, without any
// two-digit year adjustments (e.g., from "01" to 2001). Otherwise
// we made adjustments to place the 2-digit year in the proper
// century -- unless the given year itself is more than two characters.
if (count <= 2 && (pos.index - start) <= 2)
{
// Assume for example that the defaultCenturyStart is 6/18/1903.
// This means that two-digit years will be forced into the range
// 6/18/1903 to 6/17/2003. As a result, years 00, 01, and 02
// correspond to 2000, 2001, and 2002. Years 04, 05, etc. correspond
// to 1904, 1905, etc. If the year is 03, then it is 2003 if the
// other fields specify a date before 6/18, or 1903 if they specify a
// date afterwards. As a result, 03 is an ambiguous year. All other
// two-digit years are unambiguous.
int ambiguousTwoDigitYear = defaultCenturyStartYear % 100;
ambiguousYear[0] = value == ambiguousTwoDigitYear;
value += (defaultCenturyStartYear/100)*100 +
(value < ambiguousTwoDigitYear ? 100 : 0);
}
calendar.set(Calendar.YEAR, value);
return pos.index;
case 2: // 'M' - MONTH
if (count <= 2) // i.e., M or MM.
{
// Don't want to parse the month if it is a string
// while pattern uses numeric style: M or MM.
// [We computed 'value' above.]
calendar.set(Calendar.MONTH, value - 1);
return pos.index;
}
else
{
// count >= 3 // i.e., MMM or MMMM
// Want to be able to parse both short and long forms.
// Try count == 4 first:
int newStart = 0;
if ((newStart=matchString(text, start, Calendar.MONTH,
formatData.months)) > 0)
return newStart;
else // count == 4 failed, now try count == 3
return matchString(text, start, Calendar.MONTH,
formatData.shortMonths);
}
case 4: // 'k' - HOUR_OF_DAY: 1-based. eg, 23:59 + 1 hour =>> 24:59
// [We computed 'value' above.]
if (value == calendar.getMaximum(Calendar.HOUR_OF_DAY)+1) value = 0;
calendar.set(Calendar.HOUR_OF_DAY, value);
return pos.index;
case 9: { // 'E' - DAY_OF_WEEK
// Want to be able to parse both short and long forms.
// Try count == 4 (DDDD) first:
int newStart = 0;
if ((newStart=matchString(text, start, Calendar.DAY_OF_WEEK,
formatData.weekdays)) > 0)
return newStart;
else // DDDD failed, now try DDD
return matchString(text, start, Calendar.DAY_OF_WEEK,
formatData.shortWeekdays);
}
case 14: // 'a' - AM_PM
return matchString(text, start, Calendar.AM_PM, formatData.ampms);
case 15: // 'h' - HOUR:1-based. eg, 11PM + 1 hour =>> 12 AM
// [We computed 'value' above.]
if (value == calendar.getLeastMaximum(Calendar.HOUR)+1) value = 0;
calendar.set(Calendar.HOUR, value);
return pos.index;
case 17: // 'z' - ZONE_OFFSET
// First try to parse generic forms such as GMT-07:00. Do this first
// in case localized DateFormatZoneData contains the string "GMT"
// for a zone; in that case, we don't want to match the first three
// characters of GMT+/-HH:MM etc.
{
int sign = 0;
int offset;
// For time zones that have no known names, look for strings
// of the form:
// GMT[+-]hours:minutes or
// GMT[+-]hhmm or
// GMT.
if (text.regionMatches(true,start, GMT, 0, GMT.length()))
{
calendar.set(Calendar.DST_OFFSET, 0);
pos.index = start + GMT.length();
if (pos.index == text.length()) {
calendar.set(Calendar.ZONE_OFFSET, 0 );
return pos.index;
}
else if( text.charAt(pos.index) == '+' )
sign = 1;
else if( text.charAt(pos.index) == '-' )
sign = -1;
else {
calendar.set(Calendar.ZONE_OFFSET, 0 );
return pos.index;
}
// Look for hours:minutes or hhmm.
pos.index++;
Number tzNumber = numberFormat.parse(text, pos);
if( tzNumber == null ) {
return -start;
}
if( text.charAt(pos.index) == ':' ) {
// This is the hours:minutes case
offset = tzNumber.intValue() * 60;
pos.index++;
tzNumber = numberFormat.parse(text, pos);
if( tzNumber == null ) {
return -start;
}
offset += tzNumber.intValue();
}
else {
// This is the hhmm case.
offset = tzNumber.intValue();
if( offset < 24 )
offset *= 60;
else
offset = offset % 100 + offset / 100 * 60;
}
// Fall through for final processing below of 'offset' and 'sign'.
}
else {
// At this point, check for named time zones by looking through
// the locale data from the DateFormatZoneData strings.
// Want to be able to parse both short and long forms.
for (i=0; i<formatData.zoneStrings.length; i++)
{
// Checking long and short zones [1 & 2],
// and long and short daylight [3 & 4].
int j = 1;
for (; j <= 4; ++j)
{
if (text.regionMatches(true, start,
formatData.zoneStrings[i][j], 0,
formatData.zoneStrings[i][j].length()))
break;
}
if (j <= 4)
{
TimeZone tz = TimeZone.getTimeZone(formatData.zoneStrings[i][0]);
calendar.set(Calendar.ZONE_OFFSET, tz.getRawOffset());
// Must call set() with something -- TODO -- Fix this to
// use the correct DST SAVINGS for the zone.
calendar.set(Calendar.DST_OFFSET, j >= 3 ? millisPerHour : 0);
return (start + formatData.zoneStrings[i][j].length());
}
}
// As a last resort, look for numeric timezones of the form
// [+-]hhmm as specified by RFC 822. This code is actually
// a little more permissive than RFC 822. It will try to do
// its best with numbers that aren't strictly 4 digits long.
DecimalFormat fmt = new DecimalFormat("+####;-####");
fmt.setParseIntegerOnly(true);
Number tzNumber = fmt.parse( text, pos );
if( tzNumber == null ) {
return -start; // Wasn't actually a number.
}
offset = tzNumber.intValue();
sign = 1;
if( offset < 0 ) {
sign = -1;
offset = -offset;
}
if( offset < 24 )
offset = offset * 60;
else
offset = offset % 100 + offset / 100 * 60;
// Fall through for final processing below of 'offset' and 'sign'.
}
// Do the final processing for both of the above cases. We only
// arrive here if the form GMT+/-... or an RFC 822 form was seen.
if (sign != 0)
{
offset *= millisPerMinute * sign;
if (calendar.getTimeZone().useDaylightTime())
{
calendar.set(Calendar.DST_OFFSET, millisPerHour);
offset -= millisPerHour;
}
calendar.set(Calendar.ZONE_OFFSET, offset);
return pos.index;
}
}
// All efforts to parse a zone failed.
return -start;
default:
// case 3: // 'd' - DATE
// case 5: // 'H' - HOUR_OF_DAY:0-based. eg, 23:59 + 1 hour =>> 00:59
// case 6: // 'm' - MINUTE
// case 7: // 's' - SECOND
// case 8: // 'S' - MILLISECOND
// case 10: // 'D' - DAY_OF_YEAR
// case 11: // 'F' - DAY_OF_WEEK_IN_MONTH
// case 12: // 'w' - WEEK_OF_YEAR
// case 13: // 'W' - WEEK_OF_MONTH
// case 16: // 'K' - HOUR: 0-based. eg, 11PM + 1 hour =>> 0 AM
// Handle "generic" fields
if (obeyCount)
{
if ((start+count) > text.length()) return -start;
number = numberFormat.parse(text.substring(0, start+count), pos);
}
else number = numberFormat.parse(text, pos);
if (number != null)
{
calendar.set(field, number.intValue());
return pos.index;
}
return -start;
}
}
/**
* Translate a pattern, mapping each character in the from string to the
* corresponding character in the to string.
*/
private String translatePattern(String pattern, String from, String to) {
StringBuffer result = new StringBuffer();
boolean inQuote = false;
for (int i = 0; i < pattern.length(); ++i) {
char c = pattern.charAt(i);
if (inQuote) {
if (c == '\'')
inQuote = false;
}
else {
if (c == '\'')
inQuote = true;
else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
int ci = from.indexOf(c);
if (ci == -1)
throw new IllegalArgumentException("Illegal pattern " +
" character '" +
c + "'");
c = to.charAt(ci);
}
}
result.append(c);
}
if (inQuote)
throw new IllegalArgumentException("Unfinished quote in pattern");
return result.toString();
}
/**
* Return a pattern string describing this date format.
*/
public String toPattern() {
return pattern;
}
/**
* Return a localized pattern string describing this date format.
*/
public String toLocalizedPattern() {
return translatePattern(pattern,
formatData.patternChars,
formatData.localPatternChars);
}
/**
* Apply the given unlocalized pattern string to this date format.
*/
public void applyPattern (String pattern)
{
this.pattern = pattern;
}
/**
* Apply the given localized pattern string to this date format.
*/
public void applyLocalizedPattern(String pattern) {
this.pattern = translatePattern(pattern,
formatData.localPatternChars,
formatData.patternChars);
}
/**
* Gets the date/time formatting data.
* @return a copy of the date-time formatting data associated
* with this date-time formatter.
*/
public DateFormatSymbols getDateFormatSymbols()
{
return (DateFormatSymbols)formatData.clone();
}
/**
* Allows you to set the date/time formatting data.
* @param newFormatData the given date-time formatting data.
*/
public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
{
this.formatData = (DateFormatSymbols)newFormatSymbols.clone();
}
/**
* Overrides Cloneable
*/
public Object clone() {
SimpleDateFormat other = (SimpleDateFormat) super.clone();
other.formatData = (DateFormatSymbols) formatData.clone();
return other;
}
/**
* Override hashCode.
* Generates the hash code for the SimpleDateFormat object
*/
public int hashCode()
{
return pattern.hashCode();
// just enough fields for a reasonable distribution
}
/**
* Override equals.
*/
public boolean equals(Object obj)
{
if (!super.equals(obj)) return false; // super does class check
SimpleDateFormat that = (SimpleDateFormat) obj;
return (pattern.equals(that.pattern)
&& formatData.equals(that.formatData));
}
/**
* Override readObject.
*/
private void readObject(ObjectInputStream stream)
throws IOException, ClassNotFoundException {
stream.defaultReadObject();
if (serialVersionOnStream < 1) {
// didn't have defaultCenturyStart field
initializeDefaultCentury();
}
else {
// fill in dependent transient field
parseAmbiguousDatesAsAfter(defaultCenturyStart);
}
serialVersionOnStream = currentSerialVersion;
}
}
