| // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| part of intl; |
| |
| // TODO(efortuna): Customized pattern system -- suggested by i18n needs |
| // feedback on appropriateness. |
| /** |
| * DateFormat is for formatting and parsing dates in a locale-sensitive |
| * manner. |
| * It allows the user to choose from a set of standard date time formats as well |
| * as specify a customized pattern under certain locales. Date elements that |
| * vary across locales include month name, week name, field order, etc. |
| * We also allow the user to use any customized pattern to parse or format |
| * date-time strings under certain locales. Date elements that vary across |
| * locales include month name, weekname, field, order, etc. |
| * |
| * Formatting dates in the default "en_US" format does not require any |
| * initialization. e.g. |
| * print(new DateFormat.yMMMd().format(new Date.now())); |
| * |
| * But for other locales, the formatting data for the locale must be |
| * obtained. This can currently be done |
| * in one of three ways, determined by which library you import. In all cases, |
| * the "initializeDateFormatting" method must be called and will return a future |
| * that is complete once the locale data is available. The result of the future |
| * isn't important, but the data for that locale is available to the date |
| * formatting and parsing once it completes. |
| * |
| * The easiest option is that the data may be available locally, imported in a |
| * library that contains data for all the locales. |
| * import 'package:intl/date_symbol_data_local.dart'; |
| * initializeDateFormatting("fr_FR", null).then((_) => runMyCode()); |
| * |
| * If we are running outside of a browser, we may want to read the data |
| * from files in the file system. |
| * import 'package:intl/date_symbol_data_file.dart'; |
| * initializeDateFormatting("de_DE", null).then((_) => runMyCode()); |
| * |
| * If we are running in a browser, we may want to read the data from the |
| * server using the XmlHttpRequest mechanism. |
| * import 'package:intl/date_symbol_data_http_request.dart'; |
| * initializeDateFormatting("pt_BR", null).then((_) => runMyCode()); |
| * |
| * The code in example/basic/basic_example.dart shows a full example of |
| * using this mechanism. |
| * |
| * Once we have the locale data, we need to specify the particular format. |
| * This library uses the ICU/JDK date/time pattern specification both for |
| * complete format specifications and also the abbreviated "skeleton" form |
| * which can also adapt to different locales and is preferred where available. |
| * |
| * Skeletons: These can be specified either as the ICU constant name or as the |
| * skeleton to which it resolves. The supported set of skeletons is as follows |
| * ICU Name Skeleton |
| * -------- -------- |
| * DAY d |
| * ABBR_WEEKDAY E |
| * WEEKDAY EEEE |
| * ABBR_STANDALONE_MONTH LLL |
| * STANDALONE_MONTH LLLL |
| * NUM_MONTH M |
| * NUM_MONTH_DAY Md |
| * NUM_MONTH_WEEKDAY_DAY MEd |
| * ABBR_MONTH MMM |
| * ABBR_MONTH_DAY MMMd |
| * ABBR_MONTH_WEEKDAY_DAY MMMEd |
| * MONTH MMMM |
| * MONTH_DAY MMMMd |
| * MONTH_WEEKDAY_DAY MMMMEEEEd |
| * ABBR_QUARTER QQQ |
| * QUARTER QQQQ |
| * YEAR y |
| * YEAR_NUM_MONTH yM |
| * YEAR_NUM_MONTH_DAY yMd |
| * YEAR_NUM_MONTH_WEEKDAY_DAY yMEd |
| * YEAR_ABBR_MONTH yMMM |
| * YEAR_ABBR_MONTH_DAY yMMMd |
| * YEAR_ABBR_MONTH_WEEKDAY_DAY yMMMEd |
| * YEAR_MONTH yMMMM |
| * YEAR_MONTH_DAY yMMMMd |
| * YEAR_MONTH_WEEKDAY_DAY yMMMMEEEEd |
| * YEAR_ABBR_QUARTER yQQQ |
| * YEAR_QUARTER yQQQQ |
| * HOUR24 H |
| * HOUR24_MINUTE Hm |
| * HOUR24_MINUTE_SECOND Hms |
| * HOUR j |
| * HOUR_MINUTE jm |
| * HOUR_MINUTE_SECOND jms |
| * HOUR_MINUTE_GENERIC_TZ jmv |
| * HOUR_MINUTE_TZ jmz |
| * HOUR_GENERIC_TZ jv |
| * HOUR_TZ jz |
| * MINUTE m |
| * MINUTE_SECOND ms |
| * SECOND s |
| * |
| * Examples Using the US Locale: |
| * |
| * Pattern Result |
| * ---------------- ------- |
| * new DateFormat.yMd() -> 07/10/1996 |
| * new DateFormat("yMd") -> 07/10/1996 |
| * new DateFormat.yMMMMd("en_US") -> July 10, 1996 |
| * new DateFormat("Hm", "en_US") -> 12:08 PM |
| * new DateFormat.yMd().Hm() -> 07/10/1996 12:08 PM |
| * |
| * Explicit Pattern Syntax: Formats can also be specified with a pattern string. |
| * The skeleton forms will resolve to explicit patterns of this form, but will |
| * also adapt to different patterns in different locales. |
| * The following characters are reserved: |
| * |
| * Symbol Meaning Presentation Example |
| * ------ ------- ------------ ------- |
| * G era designator (Text) AD |
| * y year (Number) 1996 |
| * M month in year (Text & Number) July & 07 |
| * L standalone month (Text & Number) July & 07 |
| * d day in month (Number) 10 |
| * c standalone day (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 fractional second (Number) 978 |
| * E day of week (Text) Tuesday |
| * D day in year (Number) 189 |
| * 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 |
| * Z time zone (RFC 822) (Number) -0800 |
| * v time zone (generic) (Text) Pacific Time |
| * Q quarter (Text) Q3 |
| * ' escape for text (Delimiter) 'Date=' |
| * '' single quote (Literal) 'o''clock' |
| * |
| * The count of pattern letters determine the format. |
| * |
| * **Text**: |
| * * 5 pattern letters--use narrow form for standalone. Otherwise does not apply |
| * * 4 or more pattern letters--use full form, |
| * * 3 pattern letters--use short or abbreviated form if one exists |
| * * less than 3--use numeric form if one exists |
| * |
| * **Number**: the minimum number of digits. Shorter numbers are zero-padded to |
| * this amount (e.g. if "m" produces "6", "mm" produces "06"). Year is handled |
| * specially; that is, if the count of 'y' is 2, the Year will be truncated to |
| * 2 digits. (e.g., if "yyyy" produces "1997", "yy" produces "97".) Unlike other |
| * fields, fractional seconds are padded on the right with zero. |
| * |
| * **(Text & Number)**: 3 or over, use text, otherwise use number. |
| * |
| * Any characters not in the pattern will be treated as quoted text. For |
| * instance, characters like ':', '.', ' ', '#' and '@' will appear in the |
| * resulting text even though they are not enclosed in single quotes. In our |
| * current pattern usage, not all letters have meanings. But those unused |
| * letters are strongly discouraged to be used as quoted text without quotes, |
| * because we may use other letters as pattern characters in the future. |
| * |
| * Examples Using the US Locale: |
| * |
| * Format Pattern Result |
| * -------------- ------- |
| * "yyyy.MM.dd G 'at' HH:mm:ss vvvv" 1996.07.10 AD at 15:08:56 Pacific Time |
| * "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, vvv" 0:00 PM, PT |
| * "yyyyy.MMMMM.dd GGG hh:mm aaa" 01996.July.10 AD 12:08 PM |
| * |
| * When parsing a date string using the abbreviated year pattern ("yy"), |
| * DateFormat 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 parse function is called. For example, using a |
| * pattern of "MM/dd/yy" and a DateParse 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 |
| * java.lang.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 will be interpreted as its face value. |
| * |
| * If the year pattern does not have exactly two 'y' characters, 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. |
| */ |
| |
| class DateFormat { |
| |
| /** |
| * Creates a new DateFormat, using the format specified by [newPattern]. For |
| * forms that match one of our predefined skeletons, we look up the |
| * corresponding pattern in [locale] (or in the default locale if none is |
| * specified) and use the resulting full format string. This is the |
| * preferred usage, but if [newPattern] does not match one of the skeletons, |
| * then it is used as a format directly, but will not be adapted to suit |
| * the locale. |
| * |
| * For example, in an en_US locale, specifying the skeleton |
| * new DateFormat('yMEd'); |
| * or the explicit |
| * new DateFormat('EEE, M/d/y'); |
| * would produce the same result, a date of the form |
| * Wed, 6/27/2012 |
| * The first version would produce a different format string if used in |
| * another locale, but the second format would always be the same. |
| * |
| * If [locale] does not exist in our set of supported locales then an |
| * [ArgumentError] is thrown. |
| */ |
| DateFormat([String newPattern, String locale]) { |
| // TODO(alanknight): It should be possible to specify multiple skeletons eg |
| // date, time, timezone all separately. Adding many or named parameters to |
| // the constructor seems awkward, especially with the possibility of |
| // confusion with the locale. A "fluent" interface with cascading on an |
| // instance might work better? A list of patterns is also possible. |
| _locale = Intl.verifiedLocale(locale, localeExists); |
| addPattern(newPattern); |
| } |
| |
| /** |
| * Return a string representing [date] formatted according to our locale |
| * and internal format. |
| */ |
| String format(DateTime date) { |
| // TODO(efortuna): read optional TimeZone argument (or similar)? |
| var result = new StringBuffer(); |
| _formatFields.forEach((field) => result.write(field.format(date))); |
| return result.toString(); |
| } |
| |
| /** |
| * Returns a date string indicating how long ago (3 hours, 2 minutes) |
| * something has happened or how long in the future something will happen |
| * given a [reference] DateTime relative to the current time. |
| */ |
| String formatDuration(DateTime reference) { |
| return ''; |
| } |
| |
| /** |
| * Formats a string indicating how long ago (negative [duration]) or how far |
| * in the future (positive [duration]) some time is with respect to a |
| * reference [date]. |
| */ |
| String formatDurationFrom(Duration duration, DateTime date) { |
| return ''; |
| } |
| |
| /** |
| * Given user input, attempt to parse the [inputString] into the anticipated |
| * format, treating it as being in the local timezone. |
| */ |
| DateTime parse(String inputString, [utc = false]) { |
| // TODO(alanknight): The Closure code refers to special parsing of numeric |
| // values with no delimiters, which we currently don't do. Should we? |
| var dateFields = new _DateBuilder(); |
| if (utc) dateFields.utc=true; |
| var stream = new _Stream(inputString); |
| _formatFields.forEach( |
| (each) => each.parse(stream, dateFields)); |
| return dateFields.asDate(); |
| } |
| |
| /** |
| * Given user input, attempt to parse the [inputString] into the anticipated |
| * format, treating it as being in UTC. |
| */ |
| DateTime parseUTC(String inputString) { |
| return parse(inputString, true); |
| } |
| |
| /** |
| * Return the locale code in which we operate, e.g. 'en_US' or 'pt'. |
| */ |
| String get locale => _locale; |
| |
| /** |
| * Returns a list of all locales for which we have date formatting |
| * information. |
| */ |
| static List<String> allLocalesWithSymbols() => dateTimeSymbols.keys.toList(); |
| |
| /** |
| * The named constructors for this class are all conveniences for creating |
| * instances using one of the known "skeleton" formats, and having code |
| * completion support for discovering those formats. |
| * So, |
| * new DateFormat.yMd("en_US") |
| * is equivalent to |
| * new DateFormat("yMd", "en_US") |
| * To create a compound format you can use these constructors in combination |
| * with the add_ methods below. e.g. |
| * new DateFormat.yMd().add_Hms(); |
| * If the optional [locale] is omitted, the format will be created using the |
| * default locale in [Intl.systemLocale]. |
| */ |
| DateFormat.d([locale]) : this("d", locale); |
| DateFormat.E([locale]) : this("E", locale); |
| DateFormat.EEEE([locale]) : this("EEEE", locale); |
| DateFormat.LLL([locale]) : this("LLL", locale); |
| DateFormat.LLLL([locale]) : this("LLLL", locale); |
| DateFormat.M([locale]) : this("M", locale); |
| DateFormat.Md([locale]) : this("Md", locale); |
| DateFormat.MEd([locale]) : this("MEd", locale); |
| DateFormat.MMM([locale]) : this("MMM", locale); |
| DateFormat.MMMd([locale]) : this("MMMd", locale); |
| DateFormat.MMMEd([locale]) : this("MMMEd", locale); |
| DateFormat.MMMM([locale]) : this("MMMM", locale); |
| DateFormat.MMMMd([locale]) : this("MMMMd", locale); |
| DateFormat.MMMMEEEEd([locale]) : this("MMMMEEEEd", locale); |
| DateFormat.QQQ([locale]) : this("QQQ", locale); |
| DateFormat.QQQQ([locale]) : this("QQQQ", locale); |
| DateFormat.y([locale]) : this("y", locale); |
| DateFormat.yM([locale]) : this("yM", locale); |
| DateFormat.yMd([locale]) : this("yMd", locale); |
| DateFormat.yMEd([locale]) : this("yMEd", locale); |
| DateFormat.yMMM([locale]) : this("yMMM", locale); |
| DateFormat.yMMMd([locale]) : this("yMMMd", locale); |
| DateFormat.yMMMEd([locale]) : this("yMMMEd", locale); |
| DateFormat.yMMMM([locale]) : this("yMMMM", locale); |
| DateFormat.yMMMMd([locale]) : this("yMMMMd", locale); |
| DateFormat.yMMMMEEEEd([locale]) : this("yMMMMEEEEd", locale); |
| DateFormat.yQQQ([locale]) : this("yQQQ", locale); |
| DateFormat.yQQQQ([locale]) : this("yQQQQ", locale); |
| DateFormat.H([locale]) : this("H", locale); |
| DateFormat.Hm([locale]) : this("Hm", locale); |
| DateFormat.Hms([locale]) : this("Hms", locale); |
| DateFormat.j([locale]) : this("j", locale); |
| DateFormat.jm([locale]) : this("jm", locale); |
| DateFormat.jms([locale]) : this("jms", locale); |
| DateFormat.jmv([locale]) : this("jmv", locale); |
| DateFormat.jmz([locale]) : this("jmz", locale); |
| DateFormat.jv([locale]) : this("jv", locale); |
| DateFormat.jz([locale]) : this("jz", locale); |
| DateFormat.m([locale]) : this("m", locale); |
| DateFormat.ms([locale]) : this("ms", locale); |
| DateFormat.s([locale]) : this("s", locale); |
| |
| /** |
| * The "add_*" methods append a particular skeleton to the format, or set |
| * it as the only format if none was previously set. These are primarily |
| * useful for creating compound formats. For example |
| * new DateFormat.yMd().add_Hms(); |
| * would create a date format that prints both the date and the time. |
| */ |
| DateFormat add_d() => addPattern("d"); |
| DateFormat add_E() => addPattern("E"); |
| DateFormat add_EEEE() => addPattern("EEEE"); |
| DateFormat add_LLL() => addPattern("LLL"); |
| DateFormat add_LLLL() => addPattern("LLLL"); |
| DateFormat add_M() => addPattern("M"); |
| DateFormat add_Md() => addPattern("Md"); |
| DateFormat add_MEd() => addPattern("MEd"); |
| DateFormat add_MMM() => addPattern("MMM"); |
| DateFormat add_MMMd() => addPattern("MMMd"); |
| DateFormat add_MMMEd() => addPattern("MMMEd"); |
| DateFormat add_MMMM() => addPattern("MMMM"); |
| DateFormat add_MMMMd() => addPattern("MMMMd"); |
| DateFormat add_MMMMEEEEd() => addPattern("MMMMEEEEd"); |
| DateFormat add_QQQ() => addPattern("QQQ"); |
| DateFormat add_QQQQ() => addPattern("QQQQ"); |
| DateFormat add_y() => addPattern("y"); |
| DateFormat add_yM() => addPattern("yM"); |
| DateFormat add_yMd() => addPattern("yMd"); |
| DateFormat add_yMEd() => addPattern("yMEd"); |
| DateFormat add_yMMM() => addPattern("yMMM"); |
| DateFormat add_yMMMd() => addPattern("yMMMd"); |
| DateFormat add_yMMMEd() => addPattern("yMMMEd"); |
| DateFormat add_yMMMM() => addPattern("yMMMM"); |
| DateFormat add_yMMMMd() => addPattern("yMMMMd"); |
| DateFormat add_yMMMMEEEEd() => addPattern("yMMMMEEEEd"); |
| DateFormat add_yQQQ() => addPattern("yQQQ"); |
| DateFormat add_yQQQQ() => addPattern("yQQQQ"); |
| DateFormat add_H() => addPattern("H"); |
| DateFormat add_Hm() => addPattern("Hm"); |
| DateFormat add_Hms() => addPattern("Hms"); |
| DateFormat add_j() => addPattern("j"); |
| DateFormat add_jm() => addPattern("jm"); |
| DateFormat add_jms() => addPattern("jms"); |
| DateFormat add_jmv() => addPattern("jmv"); |
| DateFormat add_jmz() => addPattern("jmz"); |
| DateFormat add_jv() => addPattern("jv"); |
| DateFormat add_jz() => addPattern("jz"); |
| DateFormat add_m() => addPattern("m"); |
| DateFormat add_ms() => addPattern("ms"); |
| DateFormat add_s() => addPattern("s"); |
| |
| /** |
| * For each of the skeleton formats we also allow the use of the corresponding |
| * ICU constant names. |
| */ |
| static const String ABBR_MONTH = 'MMM'; |
| static const String DAY = 'd'; |
| static const String ABBR_WEEKDAY = 'E'; |
| static const String WEEKDAY = 'EEEE'; |
| static const String ABBR_STANDALONE_MONTH = 'LLL'; |
| static const String STANDALONE_MONTH = 'LLLL'; |
| static const String NUM_MONTH = 'M'; |
| static const String NUM_MONTH_DAY = 'Md'; |
| static const String NUM_MONTH_WEEKDAY_DAY = 'MEd'; |
| static const String ABBR_MONTH_DAY = 'MMMd'; |
| static const String ABBR_MONTH_WEEKDAY_DAY = 'MMMEd'; |
| static const String MONTH = 'MMMM'; |
| static const String MONTH_DAY = 'MMMMd'; |
| static const String MONTH_WEEKDAY_DAY = 'MMMMEEEEd'; |
| static const String ABBR_QUARTER = 'QQQ'; |
| static const String QUARTER = 'QQQQ'; |
| static const String YEAR = 'y'; |
| static const String YEAR_NUM_MONTH = 'yM'; |
| static const String YEAR_NUM_MONTH_DAY = 'yMd'; |
| static const String YEAR_NUM_MONTH_WEEKDAY_DAY = 'yMEd'; |
| static const String YEAR_ABBR_MONTH = 'yMMM'; |
| static const String YEAR_ABBR_MONTH_DAY = 'yMMMd'; |
| static const String YEAR_ABBR_MONTH_WEEKDAY_DAY = 'yMMMEd'; |
| static const String YEAR_MONTH = 'yMMMM'; |
| static const String YEAR_MONTH_DAY = 'yMMMMd'; |
| static const String YEAR_MONTH_WEEKDAY_DAY = 'yMMMMEEEEd'; |
| static const String YEAR_ABBR_QUARTER = 'yQQQ'; |
| static const String YEAR_QUARTER = 'yQQQQ'; |
| static const String HOUR24 = 'H'; |
| static const String HOUR24_MINUTE = 'Hm'; |
| static const String HOUR24_MINUTE_SECOND = 'Hms'; |
| static const String HOUR = 'j'; |
| static const String HOUR_MINUTE = 'jm'; |
| static const String HOUR_MINUTE_SECOND = 'jms'; |
| static const String HOUR_MINUTE_GENERIC_TZ = 'jmv'; |
| static const String HOUR_MINUTE_TZ = 'jmz'; |
| static const String HOUR_GENERIC_TZ = 'jv'; |
| static const String HOUR_TZ = 'jz'; |
| static const String MINUTE = 'm'; |
| static const String MINUTE_SECOND = 'ms'; |
| static const String SECOND = 's'; |
| |
| /** The locale in which we operate, e.g. 'en_US', or 'pt'. */ |
| String _locale; |
| |
| /** |
| * The full template string. This may have been specified directly, or |
| * it may have been derived from a skeleton and the locale information |
| * on how to interpret that skeleton. |
| */ |
| String _pattern; |
| |
| /** |
| * We parse the format string into individual [_DateFormatField] objects |
| * that are used to do the actual formatting and parsing. Do not use |
| * this variable directly, use the getter [_formatFields]. |
| */ |
| List<_DateFormatField> _formatFieldsPrivate; |
| |
| /** |
| * Getter for [_formatFieldsPrivate] that lazily initializes it. |
| */ |
| get _formatFields { |
| if (_formatFieldsPrivate == null) { |
| if (_pattern == null) _useDefaultPattern(); |
| _formatFieldsPrivate = parsePattern(_pattern); |
| } |
| return _formatFieldsPrivate; |
| } |
| |
| /** |
| * We are being asked to do formatting without having set any pattern. |
| * Use a default. |
| */ |
| _useDefaultPattern() { |
| add_yMMMMd(); |
| add_jms(); |
| } |
| |
| /** |
| * A series of regular expressions used to parse a format string into its |
| * component fields. |
| */ |
| static List<RegExp> _matchers = [ |
| // Quoted String - anything between single quotes, with escaping |
| // of single quotes by doubling them. |
| // e.g. in the pattern "hh 'o''clock'" will match 'o''clock' |
| new RegExp("^\'(?:[^\']|\'\')*\'"), |
| // Fields - any sequence of 1 or more of the same field characters. |
| // e.g. in "hh:mm:ss" will match hh, mm, and ss. But in "hms" would |
| // match each letter individually. |
| new RegExp( |
| "^(?:G+|y+|M+|k+|S+|E+|a+|h+|K+|H+|c+|L+|Q+|d+|m+|s+|v+|z+|Z+)"), |
| // Everything else - A sequence that is not quotes or field characters. |
| // e.g. in "hh:mm:ss" will match the colons. |
| new RegExp("^[^\'GyMkSEahKHcLQdmsvzZ]+") |
| ]; |
| |
| /** |
| * Set our pattern, appending it to any existing patterns. Also adds a single |
| * space to separate the two. |
| */ |
| _appendPattern(String inputPattern, [String separator = ' ']) { |
| if (_pattern == null) { |
| _pattern = inputPattern; |
| } else { |
| _pattern = "$_pattern$separator$inputPattern"; |
| } |
| } |
| |
| /** |
| * Add [inputPattern] to this instance as a pattern. If there was a previous |
| * pattern, then this appends to it, separating the two by [separator]. |
| * [inputPattern] is first looked up in our list of known skeletons. |
| * If it's found there, then use the corresponding pattern for this locale. |
| * If it's not, then treat [inputPattern] as an explicit pattern. |
| */ |
| DateFormat addPattern(String inputPattern, [String separator = ' ']) { |
| // TODO(alanknight): This is an expensive operation. Caching recently used |
| // formats, or possibly introducing an entire "locale" object that would |
| // cache patterns for that locale could be a good optimization. |
| // If we have already parsed the format fields, reset them. |
| _formatFieldsPrivate = null; |
| if (inputPattern == null) return this; |
| if (!_availableSkeletons.containsKey(inputPattern)) { |
| _appendPattern(inputPattern, separator); |
| } else { |
| _appendPattern(_availableSkeletons[inputPattern], separator); |
| } |
| return this; |
| } |
| |
| /** Return the pattern that we use to format dates.*/ |
| get pattern => _pattern; |
| |
| /** Return the skeletons for our current locale. */ |
| Map get _availableSkeletons { |
| return dateTimePatterns[locale]; |
| } |
| |
| /** |
| * Set the locale. If the locale can't be found, we also look up |
| * based on alternative versions, e.g. if we have no 'en_CA' we will |
| * look for 'en' as a fallback. It will also translate en-ca into en_CA. |
| * Null is also considered a valid value for [newLocale], indicating |
| * to use the default. |
| */ |
| _setLocale(String newLocale) { |
| _locale = Intl.verifiedLocale(newLocale, localeExists); |
| } |
| |
| /** |
| * Return true if the locale exists, or if it is null. The null case |
| * is interpreted to mean that we use the default locale. |
| */ |
| static bool localeExists(localeName) { |
| if (localeName == null) return false; |
| return dateTimeSymbols.containsKey(localeName); |
| } |
| |
| static List get _fieldConstructors => [ |
| (pattern, parent) => new _DateFormatQuotedField(pattern, parent), |
| (pattern, parent) => new _DateFormatPatternField(pattern, parent), |
| (pattern, parent) => new _DateFormatLiteralField(pattern, parent)]; |
| |
| /** Parse the template pattern and return a list of field objects.*/ |
| List parsePattern(String pattern) { |
| if (pattern == null) return null; |
| return _parsePatternHelper(pattern).reversed.toList(); |
| } |
| |
| /** Recursive helper for parsing the template pattern. */ |
| List _parsePatternHelper(String pattern) { |
| if (pattern.isEmpty) return []; |
| |
| var matched = _match(pattern); |
| if (matched == null) return []; |
| |
| var parsed = _parsePatternHelper( |
| pattern.substring(matched.fullPattern().length)); |
| parsed.add(matched); |
| return parsed; |
| } |
| |
| /** Find elements in a string that are patterns for specific fields.*/ |
| _DateFormatField _match(String pattern) { |
| for (var i = 0; i < _matchers.length; i++) { |
| var regex = _matchers[i]; |
| var match = regex.firstMatch(pattern); |
| if (match != null) { |
| return _fieldConstructors[i](match.group(0), this); |
| } |
| } |
| } |
| } |
