java.lang.Object java.text.Format java.text.DateFormat java.text.SimpleDateFormat
public class SimpleDateFormat
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.
SimpleDateFormat 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 getTimeInstance, getDateInstance, or getDateTimeInstance in DateFormat. 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 applyPattern methods as desired. For more information on using these methods, see DateFormat .
Date and time formats are specified by date and time pattern strings. Within date and time pattern strings, unquoted letters from 'A' to 'Z' and from 'a' to 'z' are interpreted as pattern letters representing the components of a date or time string. Text can be quoted using single quotes (') to avoid interpretation. "''" represents a single quote. All other characters are not interpreted; they're simply copied into the output string during formatting or matched against the input string during parsing.
The following pattern letters are defined (all other characters from 'A' to 'Z' and from 'a' to 'z' are reserved):
Pattern letters are usually repeated, as their number determines the exact presentation:
Letter Date or Time Component Presentation Examples G Era designator Text AD y Year Year 1996; 96 M Month in year Month July; Jul; 07 w Week in year Number 27 W Week in month Number 2 D Day in year Number 189 d Day in month Number 10 F Day of week in month Number 2 E Day in week Text Tuesday; Tue a Am/pm marker Text PM H Hour in day (0-23) Number 0 k Hour in day (1-24) Number 24 K Hour in am/pm (0-11) Number 0 h Hour in am/pm (1-12) Number 12 m Minute in hour Number 30 s Second in minute Number 55 S Millisecond Number 978 z Time zone General time zone Pacific Standard Time; PST; GMT-08:00 Z Time zone RFC 822 time zone -0800
For parsing, if the number of pattern letters is more than 2, the year is interpreted literally, regardless of the number of digits. So using the pattern "MM/dd/yyyy", "01/11/12" parses to Jan 11, 12 A.D.
For parsing with the abbreviated year pattern ("y" or "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 Character.isDigit(char)
GMTOffsetTimeZone: GMT Sign Hours : Minutes Sign: one of + - Hours: Digit Digit Digit Minutes: Digit Digit Digit: one of 0 1 2 3 4 5 6 7 8 9Hours must be between 0 and 23, and Minutes must be between 00 and 59. The format is locale independent and digits must be taken from the Basic Latin block of the Unicode standard.
For parsing, RFC 822 time zones are also accepted.
RFC822TimeZone: Sign TwoDigitHours Minutes TwoDigitHours: Digit DigitTwoDigitHours must be between 00 and 23. Other definitions are as for general time zones .
For parsing, general time zones are also accepted.
Date and Time Pattern Result "yyyy.MM.dd G 'at' HH:mm:ss z" 2001.07.04 AD at 12:08:56 PDT "EEE, MMM d, ''yy" Wed, Jul 4, '01 "h:mm a" 12:08 PM "hh 'o''clock' a, zzzz" 12 o'clock PM, Pacific Daylight Time "K:mm a, z" 0:08 PM, PDT "yyyyy.MMMMM.dd GGG hh:mm aaa" 02001.July.04 AD 12:08 PM "EEE, d MMM yyyy HH:mm:ss Z" Wed, 4 Jul 2001 12:08:56 -0700 "yyMMddHHmmssZ" 010704120856-0700 "yyyy-MM-dd'T'HH:mm:ss.SSSZ" 2001-07-04T12:08:56.235-0700
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.
Nested Class Summary |
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Nested classes/interfaces inherited from class java.text. DateFormat |
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DateFormat.Field |
Field Summary |
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Fields inherited from class java.text. DateFormat |
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AM_PM_FIELD , calendar , DATE_FIELD , DAY_OF_WEEK_FIELD , DAY_OF_WEEK_IN_MONTH_FIELD , DAY_OF_YEAR_FIELD , DEFAULT , ERA_FIELD , FULL , HOUR_OF_DAY0_FIELD , HOUR_OF_DAY1_FIELD , HOUR0_FIELD , HOUR1_FIELD , LONG , MEDIUM , MILLISECOND_FIELD , MINUTE_FIELD , MONTH_FIELD , numberFormat , SECOND_FIELD , SHORT , TIMEZONE_FIELD , WEEK_OF_MONTH_FIELD , WEEK_OF_YEAR_FIELD , YEAR_FIELD |
Constructor Summary | |
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SimpleDateFormat
() Constructs a SimpleDateFormat using the default pattern and date format symbols for the default locale. |
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SimpleDateFormat
(
String
pattern) Constructs a SimpleDateFormat using the given pattern and the default date format symbols for the default locale. |
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SimpleDateFormat
(
String
pattern,
DateFormatSymbols
formatSymbols) Constructs a SimpleDateFormat using the given pattern and date format symbols. |
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SimpleDateFormat
(
String
pattern,
Locale
locale) Constructs a SimpleDateFormat using the given pattern and the default date format symbols for the given locale. |
Method Summary | |
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void |
applyLocalizedPattern
(
String
pattern) Applies the given localized pattern string to this date format. |
void |
applyPattern
(
String
pattern) Applies the given pattern string to this date format. |
Object |
clone
() Creates a copy of this SimpleDateFormat. |
boolean |
equals
(
Object
obj) Compares the given object with this SimpleDateFormat for equality. |
StringBuffer |
format
(
Date
date,
StringBuffer
toAppendTo,
FieldPosition
pos) Formats the given Date into a date/time string and appends the result to the given StringBuffer. |
AttributedCharacterIterator |
formatToCharacterIterator
(
Object
obj) Formats an Object producing an AttributedCharacterIterator. |
Date |
get2DigitYearStart
() Returns the beginning date of the 100-year period 2-digit years are interpreted as being within. |
DateFormatSymbols |
getDateFormatSymbols
() Gets a copy of the date and time format symbols of this date format. |
int |
hashCode
() Returns the hash code value for this SimpleDateFormat object. |
Date |
parse
(
String
text,
ParsePosition
pos) Parses text from a string to produce a Date. |
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. |
void |
setDateFormatSymbols
(
DateFormatSymbols
newFormatSymbols) Sets the date and time format symbols of this date format. |
String |
toLocalizedPattern
() Returns a localized pattern string describing this date format. |
String |
toPattern
() Returns a pattern string describing this date format. |
Methods inherited from class java.text. DateFormat |
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format , format , getAvailableLocales , getCalendar , getDateInstance , getDateInstance , getDateInstance , getDateTimeInstance , getDateTimeInstance , getDateTimeInstance , getInstance , getNumberFormat , getTimeInstance , getTimeInstance , getTimeInstance , getTimeZone , isLenient , parse , parseObject , setCalendar , setLenient , setNumberFormat , setTimeZone |
Methods inherited from class java.text. Format |
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format , parseObject |
Methods inherited from class java.lang. Object |
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finalize , getClass , notify , notifyAll , toString , wait , wait , wait |
Constructor Detail |
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public SimpleDateFormat()
public SimpleDateFormat(String pattern)
public SimpleDateFormat(String pattern, Locale locale)
public SimpleDateFormat(String pattern, DateFormatSymbols formatSymbols)
Method Detail |
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public void set2DigitYearStart(Date startDate)
public Date get2DigitYearStart()
public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition pos)
public AttributedCharacterIterator formatToCharacterIterator(Object obj)
Each attribute key of the AttributedCharacterIterator will be of type DateFormat.Field, with the corresponding attribute value being the same as the attribute key.
public Date parse(String text, ParsePosition pos)
The method attempts to parse text starting at the index given by pos. If parsing succeeds, then the index of pos is updated to the index after the last character used (parsing does not necessarily use all characters up to the end of the string), and the parsed date is returned. The updated pos can be used to indicate the starting point for the next call to this method. If an error occurs, then the index of pos is not changed, the error index of pos is set to the index of the character where the error occurred, and null is returned.
public String toPattern()
public String toLocalizedPattern()
public void applyPattern(String pattern)
public void applyLocalizedPattern(String pattern)
public DateFormatSymbols getDateFormatSymbols()
public void setDateFormatSymbols(DateFormatSymbols newFormatSymbols)
public Object clone()
public int hashCode()
public boolean equals(Object obj)