Class SimpleDateFormat

All Implemented Interfaces:
Serializable, Cloneable
Direct Known Subclasses:
ChineseDateFormat

public class SimpleDateFormat extends DateFormat
.

SimpleDateFormat 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.

Clients are encouraged to create a date-time formatter using DateFormat.getDateInstance(), DateFormat.getDateInstance(), or DateFormat.getDateTimeInstance() rather than explicitly constructing an instance of SimpleDateFormat. This way, the client is guaranteed to get an appropriate formatting pattern for whatever locale the program is running in. If the client needs more control, they should consider using DateFormat.getInstanceForSkeleton(). However, if the client needs something more unusual than the default patterns in the locales, he can construct a SimpleDateFormat directly and give it an appropriate pattern (or use one of the factory methods on DateFormat and modify the pattern after the fact with toPattern() and applyPattern(). For more information on using these methods, see DateFormat.

Date and Time Patterns:

Date and time formats are specified by date and time pattern strings. The full syntax for date and time patterns can be found at https://unicode.org/reports/tr35/tr35-dates.html#Date_Format_Patterns.

Within date and time pattern strings, all unquoted ASCII letters [A-Za-z] are reserved as pattern letters representing calendar fields. Some of the most commonly used pattern letters are:

Sym. No. Example Description
G 1..3 AD Era - Replaced with the Era string for the current date. One to three letters for the abbreviated form, four letters for the long (wide) form, five for the narrow form.
y 1..n 1996 Year. Normally the length specifies the padding, but for two letters it also specifies the maximum length. Example:
Year y yy yyy yyyy yyyyy
AD 1 1 01 001 0001 00001
AD 12 12 12 012 0012 00012
AD 123 123 23 123 0123 00123
AD 1234 1234 34 1234 1234 01234
AD 12345 12345 45 12345 12345 12345
Q 1..2 02 Quarter - Use one or two for the numerical quarter, three for the abbreviation, or four for the full (wide) name (five for the narrow name is not yet supported).
3 Q2
4 2nd quarter
M 1..2 09 Month - Use one or two for the numerical month, three for the abbreviation, four for the full (wide) name, or five for the narrow name. With two ("MM"), the month number is zero-padded if necessary (e.g. "08").
3 Sep
4 September
5 S
d 1..2 1 Date - Day of the month. Use "d" to show the minimum number of digits, or "dd" to always show two digits (zero-padding if necessary, e.g. "08").
E 1..3 Tue Day of week - Use one through three letters for the short day, four for the full (wide) name, five for the narrow name, or six for the short name.
4 Tuesday
5 T
6 Tu
a 1 AM AM or PM
h 1..2 11 Hour [1-12]. When used in skeleton data or in a skeleton passed in an API for flexible data pattern generation, it should match the 12-hour-cycle format preferred by the locale (h or K); it should not match a 24-hour-cycle format (H or k). Use hh for zero padding.
H 1..2 13 Hour [0-23]. When used in skeleton data or in a skeleton passed in an API for flexible data pattern generation, it should match the 24-hour-cycle format preferred by the locale (H or k); it should not match a 12-hour-cycle format (h or K). Use HH for zero padding.
m 1..2 59 Minute. Use "m" to show the minimum number of digits, or "mm" to always show two digits (zero-padding if necessary, e.g. "08")..
s 1..2 12 Second. Use "s" to show the minimum number of digits, or "ss" to always show two digits (zero-padding if necessary, e.g. "08").
z 1..3 PDT Time zone. The short specific non-location format. Where that is unavailable, falls back to the short localized GMT format ("O").
4 Pacific Daylight Time The long specific non-location format. Where that is unavailable, falls back to the long localized GMT format ("OOOO").
v 1 PT Time zone. The short generic non-location format. Where that is unavailable, falls back to the generic location format ("VVVV"), then the short localized GMT format as the final fallback.
4 Pacific Time The long generic non-location format. Where that is unavailable, falls back to generic location format ("VVVV").

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.

A pattern containing any invalid pattern letter will result in a thrown exception during formatting or parsing.

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
 
Code Sample:
 SimpleTimeZone pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, "PST");
 pdt.setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY, 2*60*60*1000);
 pdt.setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY, 2*60*60*1000);
 
// Format the current time. SimpleDateFormat formatter = new SimpleDateFormat ("yyyy.MM.dd G '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);
In the example, the time value currentTime_2 obtained from parsing will be equal to currentTime_1. 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.

When parsing a date string using the abbreviated year pattern ("yy"), 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. During parsing, only strings consisting of exactly two digits, as defined by UCharacter.isDigit(int), 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.

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.

When numeric fields abut one another directly, with no intervening delimiter characters, they constitute a run of abutting numeric fields. Such runs are parsed specially. For example, the format "HHmmss" parses the input text "123456" to 12:34:56, parses the input text "12345" to 1:23:45, and fails to parse "1234". In other words, the leftmost field of the run is flexible, while the others keep a fixed width. If the parse fails anywhere in the run, then the leftmost field is shortened by one character, and the entire run is parsed again. This is repeated until either the parse succeeds or the leftmost field is one character in length. If the parse still fails at that point, the parse of the run fails.

For time zones that have no names, use strings GMT+hours:minutes or GMT-hours:minutes.

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.

Synchronization

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 Also:
  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:
    • currentSerialVersion

      static final int currentSerialVersion
      See Also:
    • DelayedHebrewMonthCheck

      static boolean DelayedHebrewMonthCheck
    • CALENDAR_FIELD_TO_LEVEL

      private static final int[] CALENDAR_FIELD_TO_LEVEL
    • PATTERN_CHAR_TO_LEVEL

      private static final int[] PATTERN_CHAR_TO_LEVEL
    • PATTERN_CHAR_IS_SYNTAX

      private static final boolean[] PATTERN_CHAR_IS_SYNTAX
    • HEBREW_CAL_CUR_MILLENIUM_START_YEAR

      private static final int HEBREW_CAL_CUR_MILLENIUM_START_YEAR
      See Also:
    • HEBREW_CAL_CUR_MILLENIUM_END_YEAR

      private static final int HEBREW_CAL_CUR_MILLENIUM_END_YEAR
      See Also:
    • serialVersionOnStream

      private int serialVersionOnStream
      The version of the serialized data on the stream. Possible values:
      • 0 or not present on stream: JDK 1.1.3. This version has no defaultCenturyStart on stream.
      • 1 JDK 1.1.4 or later. This version adds defaultCenturyStart.
      • 2 This version writes an additional int for capitalizationSetting.
      When streaming out this class, the most recent format and the highest allowable serialVersionOnStream is written.
    • pattern

      private String pattern
      The pattern string of this formatter. This is always a non-localized pattern. May not be null. See class documentation for details.
    • override

      private String override
      The override string of this formatter. Used to override the numbering system for one or more fields.
    • numberFormatters

      private HashMap<String,NumberFormat> numberFormatters
      The hash map used for number format overrides.
    • overrideMap

      private HashMap<Character,String> overrideMap
      The hash map used for number format overrides.
    • formatData

      private DateFormatSymbols formatData
      The symbols used by this formatter for week names, month names, etc. May not be null.
      See Also:
    • locale

      private transient ULocale locale
    • defaultCenturyStart

      private Date defaultCenturyStart
      We map dates with two-digit years into the century starting at defaultCenturyStart, which may be any date. May not be null.
      Since:
      JDK1.1.4
    • defaultCenturyStartYear

      private transient int defaultCenturyStartYear
    • defaultCenturyBase

      private transient long defaultCenturyBase
    • millisPerHour

      private static final int millisPerHour
      See Also:
    • ISOSpecialEra

      private static final int ISOSpecialEra
      See Also:
    • SUPPRESS_NEGATIVE_PREFIX

      private static final String SUPPRESS_NEGATIVE_PREFIX
      See Also:
    • useFastFormat

      private transient boolean useFastFormat
      If true, this object supports fast formatting using the subFormat variant that takes a StringBuffer.
    • tzFormat

      private volatile TimeZoneFormat tzFormat
    • capitalizationBrkIter

      private transient BreakIterator capitalizationBrkIter
      BreakIterator to use for capitalization (will be cloned for actual use)
    • hasMinute

      private transient boolean hasMinute
      DateFormat pattern contains the minute field.
    • hasSecond

      private transient boolean hasSecond
      DateFormat pattern contains the second field.
    • hasHanYearChar

      private transient boolean hasHanYearChar
      DateFormat pattern contains the Han year character 年=年, => non-numeric E Asian format.
    • cachedDefaultLocale

      private static ULocale cachedDefaultLocale
    • cachedDefaultPattern

      private static String cachedDefaultPattern
    • FALLBACKPATTERN

      private static final String FALLBACKPATTERN
      See Also:
    • PATTERN_CHAR_TO_INDEX

      private static final int[] PATTERN_CHAR_TO_INDEX
    • PATTERN_INDEX_TO_CALENDAR_FIELD

      private static final int[] PATTERN_INDEX_TO_CALENDAR_FIELD
    • PATTERN_INDEX_TO_DATE_FORMAT_FIELD

      private static final int[] PATTERN_INDEX_TO_DATE_FORMAT_FIELD
    • PATTERN_INDEX_TO_DATE_FORMAT_ATTRIBUTE

      private static final DateFormat.Field[] PATTERN_INDEX_TO_DATE_FORMAT_ATTRIBUTE
    • PARSED_PATTERN_CACHE

      private static ICUCache<String,Object[]> PARSED_PATTERN_CACHE
    • patternItems

      private transient Object[] patternItems
    • useLocalZeroPaddingNumberFormat

      private transient boolean useLocalZeroPaddingNumberFormat
    • decDigits

      private transient char[] decDigits
    • decimalBuf

      private transient char[] decimalBuf
    • DECIMAL_BUF_SIZE

      private static final int DECIMAL_BUF_SIZE
      See Also:
    • NUMERIC_FORMAT_CHARS

      private static final String NUMERIC_FORMAT_CHARS
      Format characters that indicate numeric fields always.
      See Also:
    • NUMERIC_FORMAT_CHARS2

      private static final String NUMERIC_FORMAT_CHARS2
      Format characters that indicate numeric fields when pattern length is up to 2.
      See Also:
    • MAX_DAYLIGHT_DETECTION_RANGE

      private static final long MAX_DAYLIGHT_DETECTION_RANGE
      Maximum range for detecting daylight offset of a time zone when parsed time zone string indicates it's daylight saving time, but the detected time zone does not observe daylight saving time at the parsed date.
      See Also:
    • DATE_PATTERN_TYPE

      static final UnicodeSet DATE_PATTERN_TYPE
  • Constructor Details

    • SimpleDateFormat

      public SimpleDateFormat()
      Constructs a SimpleDateFormat using the default pattern for the default FORMAT locale. Note: Not all locales support SimpleDateFormat; for full generality, use the factory methods in the DateFormat class.
      See Also:
    • SimpleDateFormat

      public SimpleDateFormat(String pattern)
      Constructs a SimpleDateFormat using the given pattern in the default FORMAT locale. Note: Not all locales support SimpleDateFormat; for full generality, use the factory methods in the DateFormat class.
      See Also:
    • SimpleDateFormat

      public SimpleDateFormat(String pattern, Locale loc)
      Constructs a SimpleDateFormat using the given pattern and locale. Note: Not all locales support SimpleDateFormat; for full generality, use the factory methods in the DateFormat class.
    • SimpleDateFormat

      public SimpleDateFormat(String pattern, ULocale loc)
      Constructs a SimpleDateFormat using the given pattern and locale. Note: Not all locales support SimpleDateFormat; for full generality, use the factory methods in the DateFormat class.
    • SimpleDateFormat

      public SimpleDateFormat(String pattern, String override, ULocale loc)
      Constructs a SimpleDateFormat using the given pattern , override and locale.
      Parameters:
      pattern - The pattern to be used
      override - The override string. A numbering system override string can take one of the following forms: 1). If just a numbering system name is specified, it applies to all numeric fields in the date format pattern. 2). To specify an alternate numbering system on a field by field basis, use the field letters from the pattern followed by an = sign, followed by the numbering system name. For example, to specify that just the year be formatted using Hebrew digits, use the override "y=hebr". Multiple overrides can be specified in a single string by separating them with a semi-colon. For example, the override string "m=thai;y=deva" would format using Thai digits for the month and Devanagari digits for the year.
      loc - The locale to be used
    • SimpleDateFormat

      public SimpleDateFormat(String pattern, DateFormatSymbols formatData)
      Constructs a SimpleDateFormat using the given pattern and locale-specific symbol data. Warning: uses default FORMAT locale for digits!
    • SimpleDateFormat

      @Deprecated public SimpleDateFormat(String pattern, DateFormatSymbols formatData, ULocale loc)
      Deprecated.
      This API is ICU internal only.
    • SimpleDateFormat

      SimpleDateFormat(String pattern, DateFormatSymbols formatData, Calendar calendar, ULocale locale, boolean useFastFormat, String override)
      Package-private constructor that allows a subclass to specify whether it supports fast formatting. TODO make this API public.
    • SimpleDateFormat

      private SimpleDateFormat(String pattern, DateFormatSymbols formatData, Calendar calendar, NumberFormat numberFormat, ULocale locale, boolean useFastFormat, String override)
  • Method Details

    • getLevelFromChar

      private static int getLevelFromChar(char ch)
      Map calendar field letter into calendar field level.
    • isSyntaxChar

      private static boolean isSyntaxChar(char ch)
      Tell if a character can be used to define a field in a format string.
    • getInstance

      @Deprecated public static SimpleDateFormat getInstance(Calendar.FormatConfiguration formatConfig)
      Deprecated.
      This API is ICU internal only.
      Creates an instance of SimpleDateFormat for the given format configuration
      Parameters:
      formatConfig - the format configuration
      Returns:
      A SimpleDateFormat instance
    • initialize

      private void initialize()
    • initializeTimeZoneFormat

      private void initializeTimeZoneFormat(boolean bForceUpdate)
      Private method lazily instantiate the TimeZoneFormat field
      Parameters:
      bForceUpdate - when true, check if tzFormat is synchronized with the current numberFormat and update its digits if necessary. When false, this check is skipped.
    • tzFormat

      private TimeZoneFormat tzFormat()
      Private method, returns non-null TimeZoneFormat.
      Returns:
      the TimeZoneFormat used by this formatter.
    • getDefaultPattern

      private static String getDefaultPattern()
    • parseAmbiguousDatesAsAfter

      private void parseAmbiguousDatesAsAfter(Date startDate)
    • initializeDefaultCenturyStart

      private void initializeDefaultCenturyStart(long baseTime)
    • getDefaultCenturyStart

      private Date getDefaultCenturyStart()
    • getDefaultCenturyStartYear

      private int getDefaultCenturyStartYear()
    • set2DigitYearStart

      public void set2DigitYearStart(Date startDate)
      Sets the 100-year period 2-digit years will be interpreted as being in to begin on the date the user specifies.
      Parameters:
      startDate - During parsing, two digit years will be placed in the range startDate to startDate + 100 years.
    • get2DigitYearStart

      public Date get2DigitYearStart()
      Returns the beginning date of the 100-year period 2-digit years are interpreted as being within.
      Returns:
      the start of the 100-year period into which two digit years are parsed
    • setContext

      public void setContext(DisplayContext context)
      Set a particular DisplayContext value in the formatter, such as CAPITALIZATION_FOR_STANDALONE. Note: For getContext, see DateFormat.
      Overrides:
      setContext in class DateFormat
      Parameters:
      context - The DisplayContext value to set.
    • format

      public StringBuffer format(Calendar cal, StringBuffer toAppendTo, FieldPosition pos)
      Formats a date or time, which is the standard millis since January 1, 1970, 00:00:00 GMT.

      Example: using the US locale: "yyyy.MM.dd G 'at' HH:mm:ss zzz" ->> 1996.07.10 AD at 15:08:56 PDT

      Specified by:
      format in class DateFormat
      Parameters:
      cal - the calendar whose date-time value is to be formatted into a date-time string
      toAppendTo - where the new date-time text is to be appended
      pos - the formatting position. On input: an alignment field, if desired. On output: the offsets of the alignment field.
      Returns:
      the formatted date-time string.
      See Also:
    • format

      StringBuffer format(Calendar cal, StringBuffer toAppendTo, FieldPosition pos, List<FieldPosition> attributes)
      Internal formatting method that accepts an attributes list.
    • format

      private StringBuffer format(Calendar cal, DisplayContext capitalizationContext, StringBuffer toAppendTo, FieldPosition pos, List<FieldPosition> attributes)
    • getIndexFromChar

      private static int getIndexFromChar(char ch)
    • patternCharToDateFormatField

      protected DateFormat.Field patternCharToDateFormatField(char ch)
      Returns a DateFormat.Field constant associated with the specified format pattern character.
      Parameters:
      ch - The pattern character
      Returns:
      DateFormat.Field associated with the pattern character
    • subFormat

      protected String subFormat(char ch, int count, int beginOffset, FieldPosition pos, DateFormatSymbols fmtData, Calendar cal) throws IllegalArgumentException
      Formats a single field, given its pattern character. Subclasses may override this method in order to modify or add formatting capabilities.
      Parameters:
      ch - the pattern character
      count - the number of times ch is repeated in the pattern
      beginOffset - the offset of the output string at the start of this field; used to set pos when appropriate
      pos - receives the position of a field, when appropriate
      fmtData - the symbols for this formatter
      Throws:
      IllegalArgumentException
    • subFormat

      @Deprecated protected String subFormat(char ch, int count, int beginOffset, int fieldNum, DisplayContext capitalizationContext, FieldPosition pos, char patternCharToOutput, Calendar cal)
      Deprecated.
      This API is ICU internal only.
      Formats a single field. This is the version called internally; it adds fieldNum and capitalizationContext parameters.
    • subFormat

      @Deprecated protected void subFormat(StringBuffer buf, char ch, int count, int beginOffset, int fieldNum, DisplayContext capitalizationContext, FieldPosition pos, char patternCharToOutput, Calendar cal)
      Deprecated.
      This API is ICU internal only.
      Formats a single field; useFastFormat variant. Reuses a StringBuffer for results instead of creating a String on the heap for each call. NOTE We don't really need the beginOffset parameter, EXCEPT for the need to support the slow subFormat variant (above) which has to pass it in to us.
    • safeAppend

      private static void safeAppend(String[] array, int value, StringBuffer appendTo)
    • safeAppendWithMonthPattern

      private static void safeAppendWithMonthPattern(String[] array, int value, StringBuffer appendTo, String monthPattern)
    • getPatternItems

      private Object[] getPatternItems()
    • zeroPaddingNumber

      @Deprecated protected void zeroPaddingNumber(NumberFormat nf, StringBuffer buf, int value, int minDigits, int maxDigits)
      Deprecated.
      This API is ICU internal only.
      Internal high-speed method. Reuses a StringBuffer for results instead of creating a String on the heap for each call.
    • setNumberFormat

      public void setNumberFormat(NumberFormat newNumberFormat)
      Overrides superclass method and This method also clears per field NumberFormat instances previously set by setNumberFormat(String, NumberFormat)
      Overrides:
      setNumberFormat in class DateFormat
      Parameters:
      newNumberFormat - the given new NumberFormat.
    • initLocalZeroPaddingNumberFormat

      private void initLocalZeroPaddingNumberFormat()
    • fastZeroPaddingNumber

      private void fastZeroPaddingNumber(StringBuffer buf, int value, int minDigits, int maxDigits)
    • zeroPaddingNumber

      protected String zeroPaddingNumber(long value, int minDigits, int maxDigits)
      Formats a number with the specified minimum and maximum number of digits.
    • isNumeric

      private static final boolean isNumeric(char formatChar, int count)
      Return true if the given format character, occurring count times, represents a numeric field.
    • parse

      public void parse(String text, Calendar cal, ParsePosition parsePos)
      Overrides DateFormat
      Specified by:
      parse in class DateFormat
      Parameters:
      text - The date/time string to be parsed
      cal - The calendar set on input to the date and time to be used for missing values in the date/time string being parsed, and set on output to the parsed date/time. In general, this should be initialized before calling this method - either cleared or set to the current date, depending on desired behavior. If this parse fails, the calendar may still have been modified. When the calendar type is different from the internal calendar held by this DateFormat instance, calendar field values will be parsed based on the internal calendar initialized with the time and the time zone taken from this calendar, then the parse result (time in milliseconds and time zone) will be set back to this calendar.
      parsePos - On input, the position at which to start parsing; on output, the position at which parsing terminated, or the start position if the parse failed.
      See Also:
    • matchLiteral

      private int matchLiteral(String text, int pos, Object[] items, int itemIndex, boolean[] complete)
      Matches text (starting at pos) with patl. Returns the new pos, and sets complete[0] if it matched the entire text. Whitespace sequences are treated as singletons.

      If isLenient and if we fail to match the first time, some special hacks are put into place.

      • we are between date and time fields, then one or more whitespace characters in the text are accepted instead.
        • we are after a non-numeric field, and the text starts with a ".", we skip it.
    • matchAlphaMonthStrings

      @Deprecated private int matchAlphaMonthStrings(String text, int start, String[] wideData, String[] shortData, Calendar cal)
      Deprecated.
      This API is ICU internal only. Does not handle monthPattern. field is always Calendar.MONTH
      Attempt to match the text at a given position against two arrays of month symbol strings. Since multiple strings in the array may match (for example, if the array contains "a", "ab", and "abc", all will match the input string "abcd") the longest match is returned. As a side effect, the given field of cal is set to the index of the best match, if there is one.
      Parameters:
      text - the time text being parsed.
      start - where to start parsing.
      wideData - the string array of wide month symbols
      shortData - the string array of short month symbols
      cal -
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, sets the cal field field to the index of the best match, if matching succeeded.
    • matchString

      protected int matchString(String text, int start, int field, String[] data, Calendar cal)
      Attempt to match the text at a given position against an array of strings. Since multiple strings in the array may match (for example, if the array contains "a", "ab", and "abc", all will match the input string "abcd") the longest match is returned. As a side effect, the given field of cal is set to the index of the best match, if there is one.
      Parameters:
      text - the time text being parsed.
      start - where to start parsing.
      field - the date field being parsed.
      data - the string array to parsed.
      cal -
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, sets the cal field field to the index of the best match, if matching succeeded.
    • matchString

      @Deprecated private int matchString(String text, int start, int field, String[] data, String monthPattern, Calendar cal)
      Deprecated.
      This API is ICU internal only.
      Attempt to match the text at a given position against an array of strings. Since multiple strings in the array may match (for example, if the array contains "a", "ab", and "abc", all will match the input string "abcd") the longest match is returned. As a side effect, the given field of cal is set to the index of the best match, if there is one.
      Parameters:
      text - the time text being parsed.
      start - where to start parsing.
      field - the date field being parsed.
      data - the string array to parsed.
      monthPattern - leap month pattern, or null if none.
      cal -
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, sets the cal field field to the index of the best match, if matching succeeded.
    • regionMatchesWithOptionalDot

      private int regionMatchesWithOptionalDot(String text, int start, String data, int length)
    • matchQuarterString

      protected int matchQuarterString(String text, int start, int field, String[] data, Calendar cal)
      Attempt to match the text at a given position against an array of quarter strings. Since multiple strings in the array may match (for example, if the array contains "a", "ab", and "abc", all will match the input string "abcd") the longest match is returned. As a side effect, the given field of cal is set to the index of the best match, if there is one.
      Parameters:
      text - the time text being parsed.
      start - where to start parsing.
      field - the date field being parsed.
      data - the string array to parsed.
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, sets the cal field field to the index of the best match, if matching succeeded.
    • matchDayPeriodString

      private int matchDayPeriodString(String text, int start, String[] data, int dataLength, Output<DayPeriodRules.DayPeriod> dayPeriod)
      Similar to matchQuarterString but customized for day periods.
    • subParse

      protected int subParse(String text, int start, char ch, int count, boolean obeyCount, boolean allowNegative, boolean[] ambiguousYear, Calendar cal)
      Protected method that converts one field of the input string into a numeric field value in cal. Returns -start (for ParsePosition) if failed. Subclasses may override this method to modify or add parsing capabilities.
      Parameters:
      text - the time text to be parsed.
      start - where to start parsing.
      ch - the pattern character for the date field text to be parsed.
      count - the count of a pattern character.
      obeyCount - if true, then the next field directly abuts this one, and we should use the count to know when to stop parsing.
      ambiguousYear - return parameter; upon return, if ambiguousYear[0] is true, then a two-digit year was parsed and may need to be readjusted.
      cal -
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, set the appropriate field of cal with the parsed value.
    • subParse

      private int subParse(String text, int start, char ch, int count, boolean obeyCount, boolean allowNegative, boolean[] ambiguousYear, Calendar cal, MessageFormat numericLeapMonthFormatter, Output<TimeZoneFormat.TimeType> tzTimeType)
      Overloading to provide default argument (null) for day period.
    • subParse

      @Deprecated private int subParse(String text, int start, char ch, int count, boolean obeyCount, boolean allowNegative, boolean[] ambiguousYear, Calendar cal, MessageFormat numericLeapMonthFormatter, Output<TimeZoneFormat.TimeType> tzTimeType, Output<DayPeriodRules.DayPeriod> dayPeriod)
      Deprecated.
      This API is ICU internal only.
      Protected method that converts one field of the input string into a numeric field value in cal. Returns -start (for ParsePosition) if failed. Subclasses may override this method to modify or add parsing capabilities.
      Parameters:
      text - the time text to be parsed.
      start - where to start parsing.
      ch - the pattern character for the date field text to be parsed.
      count - the count of a pattern character.
      obeyCount - if true, then the next field directly abuts this one, and we should use the count to know when to stop parsing.
      ambiguousYear - return parameter; upon return, if ambiguousYear[0] is true, then a two-digit year was parsed and may need to be readjusted.
      cal -
      numericLeapMonthFormatter - if non-null, used to parse numeric leap months.
      tzTimeType - the type of parsed time zone - standard, daylight or unknown (output). This parameter can be null if caller does not need the information.
      Returns:
      the new start position if matching succeeded; a negative number indicating matching failure, otherwise. As a side effect, set the appropriate field of cal with the parsed value.
    • allowNumericFallback

      private boolean allowNumericFallback(int patternCharIndex)
      return true if the pattern specified by patternCharIndex is one that allows numeric fallback regardless of actual pattern size.
    • parseInt

      private Number parseInt(String text, ParsePosition pos, boolean allowNegative, NumberFormat fmt)
      Parse an integer using numberFormat. This method is semantically const, but actually may modify fNumberFormat.
    • parseInt

      private Number parseInt(String text, int maxDigits, ParsePosition pos, boolean allowNegative, NumberFormat fmt)
      Parse an integer using numberFormat up to maxDigits.
    • countDigits

      private static int countDigits(String text, int start, int end)
      Counts number of digit code points in the specified text.
      Parameters:
      text - input text
      start - start index, inclusive
      end - end index, exclusive
      Returns:
      number of digits found in the text in the specified range.
    • translatePattern

      private String translatePattern(String pat, String from, String to)
      Translate a pattern, mapping each character in the from string to the corresponding character in the to string.
    • toPattern

      public String toPattern()
      Return a pattern string describing this date format.
    • toLocalizedPattern

      public String toLocalizedPattern()
      Return a localized pattern string describing this date format.

      Note: This implementation depends on DateFormatSymbols.getLocalPatternChars() to get localized format pattern characters. ICU does not include localized pattern character data, therefore, unless user sets localized pattern characters manually, this method returns the same result as toPattern().

    • applyPattern

      public void applyPattern(String pat)
      Apply the given unlocalized pattern string to this date format.
    • applyLocalizedPattern

      public void applyLocalizedPattern(String pat)
      Apply the given localized pattern string to this date format.
    • getDateFormatSymbols

      public DateFormatSymbols getDateFormatSymbols()
      Gets the date/time formatting data.
      Returns:
      a copy of the date-time formatting data associated with this date-time formatter.
    • setDateFormatSymbols

      public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
      Allows you to set the date/time formatting data.
      Parameters:
      newFormatSymbols - the new symbols
    • getSymbols

      protected DateFormatSymbols getSymbols()
      Method for subclasses to access the DateFormatSymbols.
    • getTimeZoneFormat

      public TimeZoneFormat getTimeZoneFormat()
      Gets the time zone formatter which this date/time formatter uses to format and parse a time zone.
      Returns:
      the time zone formatter which this date/time formatter uses.
    • setTimeZoneFormat

      public void setTimeZoneFormat(TimeZoneFormat tzfmt)
      Allows you to set the time zone formatter.
      Parameters:
      tzfmt - the new time zone formatter
    • clone

      public Object clone()
      Overrides Cloneable
      Overrides:
      clone in class DateFormat
    • hashCode

      public int hashCode()
      Override hashCode. Generates the hash code for the SimpleDateFormat object
      Overrides:
      hashCode in class DateFormat
    • equals

      public boolean equals(Object obj)
      Override equals.
      Overrides:
      equals in class DateFormat
    • writeObject

      private void writeObject(ObjectOutputStream stream) throws IOException
      Override writeObject. See http://docs.oracle.com/javase/6/docs/api/java/io/ObjectOutputStream.html
      Throws:
      IOException
    • readObject

      private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
      Override readObject. See http://docs.oracle.com/javase/6/docs/api/java/io/ObjectInputStream.html
      Throws:
      IOException
      ClassNotFoundException
    • formatToCharacterIterator

      public AttributedCharacterIterator formatToCharacterIterator(Object obj)
      Format the object to an attributed string, and return the corresponding iterator Overrides superclass method.
      Overrides:
      formatToCharacterIterator in class Format
      Parameters:
      obj - The object to format
      Returns:
      AttributedCharacterIterator describing the formatted value.
    • getLocale

      ULocale getLocale()
      Get the locale of this simple date formatter. It is package accessible. also used in DateIntervalFormat.
      Returns:
      locale in this simple date formatter
    • isFieldUnitIgnored

      boolean isFieldUnitIgnored(int field)
      Check whether the 'field' is smaller than all the fields covered in pattern, return true if it is. The sequence of calendar field, from large to small is: ERA, YEAR, MONTH, DATE, AM_PM, HOUR, MINUTE,...
      Parameters:
      field - the calendar field need to check against
      Returns:
      true if the 'field' is smaller than all the fields covered in pattern. false otherwise.
    • isFieldUnitIgnored

      static boolean isFieldUnitIgnored(String pattern, int field)
    • intervalFormatByAlgorithm

      @Deprecated public final StringBuffer intervalFormatByAlgorithm(Calendar fromCalendar, Calendar toCalendar, StringBuffer appendTo, FieldPosition pos) throws IllegalArgumentException
      Deprecated.
      This API is ICU internal only.
      Format date interval by algorithm. It is supposed to be used only by CLDR survey tool.
      Parameters:
      fromCalendar - calendar set to the from date in date interval to be formatted into date interval string
      toCalendar - calendar set to the to date in date interval to be formatted into date interval string
      appendTo - Output parameter to receive result. Result is appended to existing contents.
      pos - On input: an alignment field, if desired. On output: the offsets of the alignment field.
      Returns:
      Reference to 'appendTo' parameter.
      Throws:
      IllegalArgumentException - when there is non-recognized pattern letter
    • diffCalFieldValue

      private boolean diffCalFieldValue(Calendar fromCalendar, Calendar toCalendar, Object[] items, int i) throws IllegalArgumentException
      check whether the i-th item in 2 calendar is in different value. It is supposed to be used only by CLDR survey tool. It is used by intervalFormatByAlgorithm().
      Parameters:
      fromCalendar - one calendar
      toCalendar - the other calendar
      items - pattern items
      i - the i-th item in pattern items
      Returns:
      true is i-th item in 2 calendar is in different value, false otherwise.
      Throws:
      IllegalArgumentException - when there is non-recognized pattern letter
    • lowerLevel

      private boolean lowerLevel(Object[] items, int i, int level) throws IllegalArgumentException
      check whether the i-th item's level is lower than the input 'level' It is supposed to be used only by CLDR survey tool. It is used by intervalFormatByAlgorithm().
      Parameters:
      items - the pattern items
      i - the i-th item in pattern items
      level - the level with which the i-th pattern item compared to
      Returns:
      true if i-th pattern item is lower than 'level', false otherwise
      Throws:
      IllegalArgumentException - when there is non-recognized pattern letter
    • setNumberFormat

      public void setNumberFormat(String fields, NumberFormat overrideNF)
      allow the user to set the NumberFormat for several fields It can be a single field like: "y"(year) or "M"(month) It can be several field combined together: "yMd"(year, month and date) Note: 1 symbol field is enough for multiple symbol fields (so "y" will override "yy", "yyy") If the field is not numeric, then override has no effect (like "MMM" will use abbreviation, not numerical field)
      Parameters:
      fields - the fields to override
      overrideNF - the NumbeferFormat used
      Throws:
      IllegalArgumentException - when the fields contain invalid field
    • getNumberFormat

      public NumberFormat getNumberFormat(char field)
      give the NumberFormat used for the field like 'y'(year) and 'M'(year)
      Parameters:
      field - the field the user wants
      Returns:
      override NumberFormat used for the field
    • initNumberFormatters

      private void initNumberFormatters(ULocale loc)
    • processOverrideString

      private void processOverrideString(ULocale loc, String str)
    • parsePattern

      private void parsePattern()