public final class DateTimeFormatter extends Object
This class provides the main application entry point for printing and parsing
and provides common implementations of DateTimeFormatter
:
ISO_LOCAL_DATE
uuuu-MMM-dd
long
or medium
More complex formatters are provided by
DateTimeFormatterBuilder
.
The main date-time classes provide two methods - one for formatting,
format(DateTimeFormatter formatter)
, and one for parsing,
parse(CharSequence text, DateTimeFormatter formatter)
.
For example:
LocalDate date = LocalDate.now(); String text = date.format(formatter); LocalDate parsedDate = LocalDate.parse(text, formatter);
In addition to the format, formatters can be created with desired Locale, Chronology, ZoneId, and DecimalStyle.
The withLocale
method returns a new formatter that
overrides the locale. The locale affects some aspects of formatting and
parsing. For example, the ofLocalizedDate
provides a
formatter that uses the locale specific date format.
The withChronology
method returns a new formatter
that overrides the chronology. If overridden, the date-time value is
converted to the chronology before formatting. During parsing the date-time
value is converted to the chronology before it is returned.
The withZone
method returns a new formatter that overrides
the zone. If overridden, the date-time value is converted to a ZonedDateTime
with the requested ZoneId before formatting. During parsing the ZoneId is
applied before the value is returned.
The withDecimalStyle
method returns a new formatter that
overrides the DecimalStyle
. The DecimalStyle symbols are used for
formatting and parsing.
Some applications may need to use the older java.text.Format
class for formatting. The toFormat()
method returns an
implementation of java.text.Format
.
Formatter | Description | Example |
---|---|---|
ofLocalizedDate(dateStyle) |
Formatter with date style from the locale | '2011-12-03' |
ofLocalizedTime(timeStyle) |
Formatter with time style from the locale | '10:15:30' |
ofLocalizedDateTime(dateTimeStyle) |
Formatter with a style for date and time from the locale | '3 Jun 2008 11:05:30' |
ofLocalizedDateTime(dateStyle,timeStyle)
|
Formatter with date and time styles from the locale | '3 Jun 2008 11:05' |
BASIC_ISO_DATE |
Basic ISO date | '20111203' |
ISO_LOCAL_DATE |
ISO Local Date | '2011-12-03' |
ISO_OFFSET_DATE |
ISO Date with offset | '2011-12-03+01:00' |
ISO_DATE |
ISO Date with or without offset | '2011-12-03+01:00'; '2011-12-03' |
ISO_LOCAL_TIME |
Time without offset | '10:15:30' |
ISO_OFFSET_TIME |
Time with offset | '10:15:30+01:00' |
ISO_TIME |
Time with or without offset | '10:15:30+01:00'; '10:15:30' |
ISO_LOCAL_DATE_TIME |
ISO Local Date and Time | '2011-12-03T10:15:30' |
ISO_OFFSET_DATE_TIME |
Date Time with Offset | 2011-12-03T10:15:30+01:00' |
ISO_ZONED_DATE_TIME |
Zoned Date Time | '2011-12-03T10:15:30+01:00[Europe/Paris]' |
ISO_DATE_TIME |
Date and time with ZoneId | '2011-12-03T10:15:30+01:00[Europe/Paris]' |
ISO_ORDINAL_DATE |
Year and day of year | '2012-337' |
ISO_WEEK_DATE |
Year and Week | 2012-W48-6' |
ISO_INSTANT |
Date and Time of an Instant | '2011-12-03T10:15:30Z' |
RFC_1123_DATE_TIME |
RFC 1123 / RFC 822 | 'Tue, 3 Jun 2008 11:05:30 GMT' |
ofPattern(String)
and ofPattern(String, Locale)
methods.
For example,
"d MMM uuuu"
will format 2011-12-03 as '3 Dec 2011'.
A formatter created from a pattern can be used as many times as necessary,
it is immutable and is thread-safe.
For example:
LocalDate date = LocalDate.now(); DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy MM dd"); String text = date.format(formatter); LocalDate parsedDate = LocalDate.parse(text, formatter);
All letters 'A' to 'Z' and 'a' to 'z' are reserved as pattern letters. The following pattern letters are defined:
Symbol Meaning Presentation Examples ------ ------- ------------ ------- G era text AD; Anno Domini; A u year year 2004; 04 y year-of-era year 2004; 04 D day-of-year number 189 M/L month-of-year number/text 7; 07; Jul; July; J d day-of-month number 10 Q/q quarter-of-year number/text 3; 03; Q3; 3rd quarter Y week-based-year year 1996; 96 w week-of-week-based-year number 27 W week-of-month number 4 E day-of-week text Tue; Tuesday; T e/c localized day-of-week number/text 2; 02; Tue; Tuesday; T F week-of-month number 3 a am-pm-of-day text PM h clock-hour-of-am-pm (1-12) number 12 K hour-of-am-pm (0-11) number 0 k clock-hour-of-am-pm (1-24) number 0 H hour-of-day (0-23) number 0 m minute-of-hour number 30 s second-of-minute number 55 S fraction-of-second fraction 978 A milli-of-day number 1234 n nano-of-second number 987654321 N nano-of-day number 1234000000 V time-zone ID zone-id America/Los_Angeles; Z; -08:30 z time-zone name zone-name Pacific Standard Time; PST O localized zone-offset offset-O GMT+8; GMT+08:00; UTC-08:00; X zone-offset 'Z' for zero offset-X Z; -08; -0830; -08:30; -083015; -08:30:15; x zone-offset offset-x +0000; -08; -0830; -08:30; -083015; -08:30:15; Z zone-offset offset-Z +0000; -0800; -08:00; p pad next pad modifier 1 ' escape for text delimiter '' single quote literal ' [ optional section start ] optional section end # reserved for future use { reserved for future use } reserved for future use
The count of pattern letters determines the format.
Text: The text style is determined based on the number of pattern
letters used. Less than 4 pattern letters will use the
short form
. Exactly 4 pattern letters will use the
full form
. Exactly 5 pattern letters will use the
narrow form
.
Pattern letters 'L', 'c', and 'q' specify the stand-alone form of the text styles.
Number: If the count of letters is one, then the value is output using the minimum number of digits and without padding. Otherwise, the count of digits is used as the width of the output field, with the value zero-padded as necessary. The following pattern letters have constraints on the count of letters. Only one letter of 'c' and 'F' can be specified. Up to two letters of 'd', 'H', 'h', 'K', 'k', 'm', and 's' can be specified. Up to three letters of 'D' can be specified.
Number/Text: If the count of pattern letters is 3 or greater, use the Text rules above. Otherwise use the Number rules above.
Fraction: Outputs the nano-of-second field as a fraction-of-second. The nano-of-second value has nine digits, thus the count of pattern letters is from 1 to 9. If it is less than 9, then the nano-of-second value is truncated, with only the most significant digits being output.
Year: The count of letters determines the minimum field width below
which padding is used. If the count of letters is two, then a
reduced
two digit form is
used. For printing, this outputs the rightmost two digits. For parsing, this
will parse using the base value of 2000, resulting in a year within the range
2000 to 2099 inclusive. If the count of letters is less than four (but not
two), then the sign is only output for negative years as per
SignStyle.NORMAL
. Otherwise, the sign is output if the pad width is
exceeded, as per SignStyle.EXCEEDS_PAD
.
ZoneId: This outputs the time-zone ID, such as 'Europe/Paris'. If the
count of letters is two, then the time-zone ID is output. Any other count of
letters throws IllegalArgumentException
.
Zone names: This outputs the display name of the time-zone ID. If the
count of letters is one, two or three, then the short name is output. If the
count of letters is four, then the full name is output. Five or more letters
throws IllegalArgumentException
.
Offset X and x: This formats the offset based on the number of pattern
letters. One letter outputs just the hour, such as '+01', unless the minute
is non-zero in which case the minute is also output, such as '+0130'. Two
letters outputs the hour and minute, without a colon, such as '+0130'. Three
letters outputs the hour and minute, with a colon, such as '+01:30'. Four
letters outputs the hour and minute and optional second, without a colon,
such as '+013015'. Five letters outputs the hour and minute and optional
second, with a colon, such as '+01:30:15'. Six or more letters throws
IllegalArgumentException
. Pattern letter 'X' (upper case) will output
'Z' when the offset to be output would be zero, whereas pattern letter 'x'
(lower case) will output '+00', '+0000', or '+00:00'.
Offset O: This formats the localized offset based on the number of
pattern letters. One letter outputs the short
form of the localized offset, which is localized offset text, such as 'GMT',
with hour without leading zero, optional 2-digit minute and second if
non-zero, and colon, for example 'GMT+8'. Four letters outputs the
full form, which is localized offset text,
such as 'GMT, with 2-digit hour and minute field, optional second field
if non-zero, and colon, for example 'GMT+08:00'. Any other count of letters
throws IllegalArgumentException
.
Offset Z: This formats the offset based on the number of pattern
letters. One, two or three letters outputs the hour and minute, without a
colon, such as '+0130'. The output will be '+0000' when the offset is zero.
Four letters outputs the full form of localized
offset, equivalent to four letters of Offset-O. The output will be the
corresponding localized offset text if the offset is zero. Five
letters outputs the hour, minute, with optional second if non-zero, with
colon. It outputs 'Z' if the offset is zero.
Six or more letters throws IllegalArgumentException
.
Optional section: The optional section markers work exactly like
calling DateTimeFormatterBuilder.optionalStart()
and
DateTimeFormatterBuilder.optionalEnd()
.
Pad modifier: Modifies the pattern that immediately follows to be
padded with spaces. The pad width is determined by the number of pattern
letters. This is the same as calling
DateTimeFormatterBuilder.padNext(int)
.
For example, 'ppH' outputs the hour-of-day padded on the left with spaces to a width of 2.
Any unrecognized letter is an error. Any non-letter character, other than '[', ']', '{', '}', '#' and the single quote will be output directly. Despite this, it is recommended to use single quotes around all characters that you want to output directly to ensure that future changes do not break your application.
Map
of field to value, a ZoneId
and a Chronology
.
Second, the parsed data is resolved, by validating, combining and
simplifying the various fields into more useful ones.
Five parsing methods are supplied by this class.
Four of these perform both the parse and resolve phases.
The fifth method, parseUnresolved(CharSequence, ParsePosition)
,
only performs the first phase, leaving the result unresolved.
As such, it is essentially a low-level operation.
The resolve phase is controlled by two parameters, set on this class.
The ResolverStyle
is an enum that offers three different approaches,
strict, smart and lenient. The smart option is the default.
It can be set using withResolverStyle(ResolverStyle)
.
The withResolverFields(TemporalField...)
parameter allows the
set of fields that will be resolved to be filtered before resolving starts.
For example, if the formatter has parsed a year, month, day-of-month
and day-of-year, then there are two approaches to resolve a date:
(year + month + day-of-month) and (year + day-of-year).
The resolver fields allows one of the two approaches to be selected.
If no resolver fields are set then both approaches must result in the same date.
Resolving separate fields to form a complete date and time is a complex process with behaviour distributed across a number of classes. It follows these steps:
IsoChronology
.
ChronoField
date fields are resolved.
This is achieved using Chronology.resolveDate(Map, ResolverStyle)
.
Documentation about field resolution is located in the implementation
of Chronology
.
ChronoField
time fields are resolved.
This is documented on ChronoField
and is the same for all chronologies.
ChronoField
are processed.
This is achieved using TemporalField.resolve(Map, TemporalAccessor, ResolverStyle)
.
Documentation about field resolution is located in the implementation
of TemporalField
.
ChronoField
date and time fields are re-resolved.
This allows fields in step four to produce ChronoField
values
and have them be processed into dates and times.
LocalTime
is formed if there is at least an hour-of-day available.
This involves providing default values for minute, second and fraction of second.
Modifier and Type | Field and Description |
---|---|
static DateTimeFormatter |
BASIC_ISO_DATE
The ISO date formatter that formats or parses a date without an
offset, such as '20111203'.
|
static DateTimeFormatter |
ISO_DATE
The ISO date formatter that formats or parses a date with the
offset if available, such as '2011-12-03' or '2011-12-03+01:00'.
|
static DateTimeFormatter |
ISO_DATE_TIME
The ISO-like date-time formatter that formats or parses a date-time with
the offset and zone if available, such as '2011-12-03T10:15:30',
'2011-12-03T10:15:30+01:00' or '2011-12-03T10:15:30+01:00[Europe/Paris]'.
|
static DateTimeFormatter |
ISO_INSTANT
The ISO instant formatter that formats or parses an instant in UTC,
such as '2011-12-03T10:15:30Z'.
|
static DateTimeFormatter |
ISO_LOCAL_DATE
The ISO date formatter that formats or parses a date without an
offset, such as '2011-12-03'.
|
static DateTimeFormatter |
ISO_LOCAL_DATE_TIME
The ISO date-time formatter that formats or parses a date-time without
an offset, such as '2011-12-03T10:15:30'.
|
static DateTimeFormatter |
ISO_LOCAL_TIME
The ISO time formatter that formats or parses a time without an
offset, such as '10:15' or '10:15:30'.
|
static DateTimeFormatter |
ISO_OFFSET_DATE
The ISO date formatter that formats or parses a date with an
offset, such as '2011-12-03+01:00'.
|
static DateTimeFormatter |
ISO_OFFSET_DATE_TIME
The ISO date-time formatter that formats or parses a date-time with an
offset, such as '2011-12-03T10:15:30+01:00'.
|
static DateTimeFormatter |
ISO_OFFSET_TIME
The ISO time formatter that formats or parses a time with an
offset, such as '10:15+01:00' or '10:15:30+01:00'.
|
static DateTimeFormatter |
ISO_ORDINAL_DATE
The ISO date formatter that formats or parses the ordinal date
without an offset, such as '2012-337'.
|
static DateTimeFormatter |
ISO_TIME
The ISO time formatter that formats or parses a time, with the
offset if available, such as '10:15', '10:15:30' or '10:15:30+01:00'.
|
static DateTimeFormatter |
ISO_WEEK_DATE
The ISO date formatter that formats or parses the week-based date
without an offset, such as '2012-W48-6'.
|
static DateTimeFormatter |
ISO_ZONED_DATE_TIME
The ISO-like date-time formatter that formats or parses a date-time with
offset and zone, such as '2011-12-03T10:15:30+01:00[Europe/Paris]'.
|
static DateTimeFormatter |
RFC_1123_DATE_TIME
The RFC-1123 date-time formatter, such as 'Tue, 3 Jun 2008 11:05:30 GMT'.
|
Modifier and Type | Method and Description |
---|---|
String |
format(TemporalAccessor temporal)
Formats a date-time object using this formatter.
|
void |
formatTo(TemporalAccessor temporal,
Appendable appendable)
Formats a date-time object to an
Appendable using this formatter. |
Chronology |
getChronology()
Gets the overriding chronology to be used during formatting.
|
DecimalStyle |
getDecimalStyle()
Gets the DecimalStyle to be used during formatting.
|
Locale |
getLocale()
Gets the locale to be used during formatting.
|
Set<TemporalField> |
getResolverFields()
Gets the resolver fields to use during parsing.
|
ResolverStyle |
getResolverStyle()
Gets the resolver style to use during parsing.
|
ZoneId |
getZone()
Gets the overriding zone to be used during formatting.
|
static DateTimeFormatter |
ofLocalizedDate(FormatStyle dateStyle)
Returns a locale specific date format for the ISO chronology.
|
static DateTimeFormatter |
ofLocalizedDateTime(FormatStyle dateTimeStyle)
Returns a locale specific date-time formatter for the ISO chronology.
|
static DateTimeFormatter |
ofLocalizedDateTime(FormatStyle dateStyle,
FormatStyle timeStyle)
Returns a locale specific date and time format for the ISO chronology.
|
static DateTimeFormatter |
ofLocalizedTime(FormatStyle timeStyle)
Returns a locale specific time format for the ISO chronology.
|
static DateTimeFormatter |
ofPattern(String pattern)
Creates a formatter using the specified pattern.
|
static DateTimeFormatter |
ofPattern(String pattern,
Locale locale)
Creates a formatter using the specified pattern and locale.
|
TemporalAccessor |
parse(CharSequence text)
Fully parses the text producing a temporal object.
|
TemporalAccessor |
parse(CharSequence text,
ParsePosition position)
Parses the text using this formatter, providing control over the text position.
|
<T> T |
parse(CharSequence text,
TemporalQuery<T> query)
Fully parses the text producing an object of the specified type.
|
TemporalAccessor |
parseBest(CharSequence text,
TemporalQuery<?>... queries)
Fully parses the text producing an object of one of the specified types.
|
static TemporalQuery<Period> |
parsedExcessDays()
A query that provides access to the excess days that were parsed.
|
static TemporalQuery<Boolean> |
parsedLeapSecond()
A query that provides access to whether a leap-second was parsed.
|
TemporalAccessor |
parseUnresolved(CharSequence text,
ParsePosition position)
Parses the text using this formatter, without resolving the result, intended
for advanced use cases.
|
Format |
toFormat()
Returns this formatter as a
java.text.Format instance. |
Format |
toFormat(TemporalQuery<?> parseQuery)
Returns this formatter as a
java.text.Format instance that will
parse using the specified query. |
String |
toString()
Returns a description of the underlying formatters.
|
DateTimeFormatter |
withChronology(Chronology chrono)
Returns a copy of this formatter with a new override chronology.
|
DateTimeFormatter |
withDecimalStyle(DecimalStyle decimalStyle)
Returns a copy of this formatter with a new DecimalStyle.
|
DateTimeFormatter |
withLocale(Locale locale)
Returns a copy of this formatter with a new locale.
|
DateTimeFormatter |
withResolverFields(Set<TemporalField> resolverFields)
Returns a copy of this formatter with a new set of resolver fields.
|
DateTimeFormatter |
withResolverFields(TemporalField... resolverFields)
Returns a copy of this formatter with a new set of resolver fields.
|
DateTimeFormatter |
withResolverStyle(ResolverStyle resolverStyle)
Returns a copy of this formatter with a new resolver style.
|
DateTimeFormatter |
withZone(ZoneId zone)
Returns a copy of this formatter with a new override zone.
|
public static final DateTimeFormatter ISO_LOCAL_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended local date format. The format consists of:
year
.
Years in the range 0000 to 9999 will be pre-padded by zero to ensure four digits.
Years outside that range will have a prefixed positive or negative symbol.
month-of-year
.
This is pre-padded by zero to ensure two digits.
day-of-month
.
This is pre-padded by zero to ensure two digits.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_OFFSET_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended offset date format. The format consists of:
ISO_LOCAL_DATE
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended date format. The format consists of:
ISO_LOCAL_DATE
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_LOCAL_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended local time format. The format consists of:
hour-of-day
.
This is pre-padded by zero to ensure two digits.
minute-of-hour
.
This is pre-padded by zero to ensure two digits.
second-of-minute
.
This is pre-padded by zero to ensure two digits.
nano-of-second
.
As many digits will be output as required.
The returned formatter has no override chronology or zone.
It uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_OFFSET_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended offset time format. The format consists of:
ISO_LOCAL_TIME
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
The returned formatter has no override chronology or zone.
It uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended offset time format. The format consists of:
ISO_LOCAL_TIME
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has no override chronology or zone.
It uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_LOCAL_DATE_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended offset date-time format. The format consists of:
ISO_LOCAL_DATE
ISO_LOCAL_TIME
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_OFFSET_DATE_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended offset date-time format. The format consists of:
ISO_LOCAL_DATE_TIME
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_ZONED_DATE_TIME
This returns an immutable formatter capable of formatting and parsing a format that extends the ISO-8601 extended offset date-time format to add the time-zone. The section in square brackets is not part of the ISO-8601 standard. The format consists of:
ISO_OFFSET_DATE_TIME
ZoneOffset
then the format is complete.
zone ID
. This is not part of the ISO-8601 standard.
Parsing is case sensitive.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_DATE_TIME
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended local or offset date-time format, as well as the extended non-ISO form specifying the time-zone. The format consists of:
ISO_LOCAL_DATE_TIME
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
ZoneOffset
then the format is complete.
zone ID
. This is not part of the ISO-8601 standard.
Parsing is case sensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_ORDINAL_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended ordinal date format. The format consists of:
year
.
Years in the range 0000 to 9999 will be pre-padded by zero to ensure four digits.
Years outside that range will have a prefixed positive or negative symbol.
day-of-year
.
This is pre-padded by zero to ensure three digits.
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_WEEK_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 extended week-based date format. The format consists of:
week-based-year
.
Years in the range 0000 to 9999 will be pre-padded by zero to ensure four digits.
Years outside that range will have a prefixed positive or negative symbol.
week-of-week-based-year
.
This is pre-padded by zero to ensure three digits.
day-of-week
.
The value run from Monday (1) to Sunday (7).
offset ID
. If the offset has seconds then
they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter ISO_INSTANT
This returns an immutable formatter capable of formatting and parsing the ISO-8601 instant format. When formatting, the second-of-minute is always output. The nano-of-second outputs zero, three, six or nine digits digits as necessary. When parsing, time to at least the seconds field is required. Fractional seconds from zero to nine are parsed. The localized decimal style is not used.
This is a special case formatter intended to allow a human readable form
of an Instant
. The Instant
class is designed to
only represent a point in time and internally stores a value in nanoseconds
from a fixed epoch of 1970-01-01Z. As such, an Instant
cannot be
formatted as a date or time without providing some form of time-zone.
This formatter allows the Instant
to be formatted, by providing
a suitable conversion using ZoneOffset.UTC
.
The format consists of:
ISO_OFFSET_DATE_TIME
where the instant is converted from
ChronoField.INSTANT_SECONDS
and ChronoField.NANO_OF_SECOND
using the UTC
offset. Parsing is case insensitive.
The returned formatter has no override chronology or zone.
It uses the STRICT
resolver style.
public static final DateTimeFormatter BASIC_ISO_DATE
This returns an immutable formatter capable of formatting and parsing the ISO-8601 basic local date format. The format consists of:
year
.
Only years in the range 0000 to 9999 are supported.
month-of-year
.
This is pre-padded by zero to ensure two digits.
day-of-month
.
This is pre-padded by zero to ensure two digits.
offset ID
without colons. If the offset has
seconds then they will be handled even though this is not part of the ISO-8601 standard.
Parsing is case insensitive.
As this formatter has an optional element, it may be necessary to parse using
parseBest(java.lang.CharSequence, java.time.temporal.TemporalQuery<?>...)
.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the STRICT
resolver style.
public static final DateTimeFormatter RFC_1123_DATE_TIME
This returns an immutable formatter capable of formatting and parsing most of the RFC-1123 format. RFC-1123 updates RFC-822 changing the year from two digits to four. This implementation requires a four digit year. This implementation also does not handle North American or military zone names, only 'GMT' and offset amounts.
The format consists of:
day-of-week
in English.
day-of-month
.
month-of-year
in English.
year
.
Only years in the range 0000 to 9999 are supported.
hour-of-day
.
This is pre-padded by zero to ensure two digits.
minute-of-hour
.
This is pre-padded by zero to ensure two digits.
second-of-minute
.
This is pre-padded by zero to ensure two digits.
offset ID
without colons or seconds.
An offset of zero uses "GMT". North American zone names and military zone names are not handled.
Parsing is case insensitive.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the SMART
resolver style.
public static DateTimeFormatter ofPattern(String pattern)
This method will create a formatter based on a simple
pattern of letters and symbols
as described in the class documentation.
For example, d MMM uuuu
will format 2011-12-03 as '3 Dec 2011'.
The formatter will use the default FORMAT locale
.
This can be changed using withLocale(Locale)
on the returned formatter
Alternatively use the ofPattern(String, Locale)
variant of this method.
The returned formatter has no override chronology or zone.
It uses SMART
resolver style.
pattern
- the pattern to use, not nullIllegalArgumentException
- if the pattern is invalidDateTimeFormatterBuilder.appendPattern(String)
public static DateTimeFormatter ofPattern(String pattern, Locale locale)
This method will create a formatter based on a simple
pattern of letters and symbols
as described in the class documentation.
For example, d MMM uuuu
will format 2011-12-03 as '3 Dec 2011'.
The formatter will use the specified locale.
This can be changed using withLocale(Locale)
on the returned formatter
The returned formatter has no override chronology or zone.
It uses SMART
resolver style.
pattern
- the pattern to use, not nulllocale
- the locale to use, not nullIllegalArgumentException
- if the pattern is invalidDateTimeFormatterBuilder.appendPattern(String)
public static DateTimeFormatter ofLocalizedDate(FormatStyle dateStyle)
This returns a formatter that will format or parse a date. The exact format pattern used varies by locale.
The locale is determined from the formatter. The formatter returned directly by
this method will use the default FORMAT locale
.
The locale can be controlled using withLocale(Locale)
on the result of this method.
Note that the localized pattern is looked up lazily.
This DateTimeFormatter
holds the style required and the locale,
looking up the pattern required on demand.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the SMART
resolver style.
dateStyle
- the formatter style to obtain, not nullpublic static DateTimeFormatter ofLocalizedTime(FormatStyle timeStyle)
This returns a formatter that will format or parse a time. The exact format pattern used varies by locale.
The locale is determined from the formatter. The formatter returned directly by
this method will use the default FORMAT locale
.
The locale can be controlled using withLocale(Locale)
on the result of this method.
Note that the localized pattern is looked up lazily.
This DateTimeFormatter
holds the style required and the locale,
looking up the pattern required on demand.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the SMART
resolver style.
timeStyle
- the formatter style to obtain, not nullpublic static DateTimeFormatter ofLocalizedDateTime(FormatStyle dateTimeStyle)
This returns a formatter that will format or parse a date-time. The exact format pattern used varies by locale.
The locale is determined from the formatter. The formatter returned directly by
this method will use the default FORMAT locale
.
The locale can be controlled using withLocale(Locale)
on the result of this method.
Note that the localized pattern is looked up lazily.
This DateTimeFormatter
holds the style required and the locale,
looking up the pattern required on demand.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the SMART
resolver style.
dateTimeStyle
- the formatter style to obtain, not nullpublic static DateTimeFormatter ofLocalizedDateTime(FormatStyle dateStyle, FormatStyle timeStyle)
This returns a formatter that will format or parse a date-time. The exact format pattern used varies by locale.
The locale is determined from the formatter. The formatter returned directly by
this method will use the default FORMAT locale
.
The locale can be controlled using withLocale(Locale)
on the result of this method.
Note that the localized pattern is looked up lazily.
This DateTimeFormatter
holds the style required and the locale,
looking up the pattern required on demand.
The returned formatter has a chronology of ISO set to ensure dates in
other calendar systems are correctly converted.
It has no override zone and uses the SMART
resolver style.
dateStyle
- the date formatter style to obtain, not nulltimeStyle
- the time formatter style to obtain, not nullpublic static final TemporalQuery<Period> parsedExcessDays()
This returns a singleton query that provides access to additional information from the parse. The query always returns a non-null period, with a zero period returned instead of null.
There are two situations where this query may return a non-zero period.
ResolverStyle
is LENIENT
and a time is parsed
without a date, then the complete result of the parse consists of a
LocalTime
and an excess Period
in days.
ResolverStyle
is SMART
and a time is parsed
without a date where the time is 24:00:00, then the complete result of
the parse consists of a LocalTime
of 00:00:00 and an excess
Period
of one day.
In both cases, if a complete ChronoLocalDateTime
or Instant
is parsed, then the excess days are added to the date part.
As a result, this query will return a zero period.
The SMART
behaviour handles the common "end of day" 24:00 value.
Processing in LENIENT
mode also produces the same result:
Text to parse Parsed object Excess days "2012-12-03T00:00" LocalDateTime.of(2012, 12, 3, 0, 0) ZERO "2012-12-03T24:00" LocalDateTime.of(2012, 12, 4, 0, 0) ZERO "00:00" LocalTime.of(0, 0) ZERO "24:00" LocalTime.of(0, 0) Period.ofDays(1)The query can be used as follows:
TemporalAccessor parsed = formatter.parse(str); LocalTime time = parsed.query(LocalTime::from); Period extraDays = parsed.query(DateTimeFormatter.parsedExcessDays());
public static final TemporalQuery<Boolean> parsedLeapSecond()
This returns a singleton query that provides access to additional information from the parse. The query always returns a non-null boolean, true if parsing saw a leap-second, false if not.
Instant parsing handles the special "leap second" time of '23:59:60'.
Leap seconds occur at '23:59:60' in the UTC time-zone, but at other
local times in different time-zones. To avoid this potential ambiguity,
the handling of leap-seconds is limited to
DateTimeFormatterBuilder.appendInstant()
, as that method
always parses the instant with the UTC zone offset.
If the time '23:59:60' is received, then a simple conversion is applied,
replacing the second-of-minute of 60 with 59. This query can be used
on the parse result to determine if the leap-second adjustment was made.
The query will return true
if it did adjust to remove the
leap-second, and false
if not. Note that applying a leap-second
smoothing mechanism, such as UTC-SLS, is the responsibility of the
application, as follows:
TemporalAccessor parsed = formatter.parse(str); Instant instant = parsed.query(Instant::from); if (parsed.query(DateTimeFormatter.parsedLeapSecond())) { // validate leap-second is correct and apply correct smoothing }
public Locale getLocale()
This is used to lookup any part of the formatter needing specific localization, such as the text or localized pattern.
public DateTimeFormatter withLocale(Locale locale)
This is used to lookup any part of the formatter needing specific localization, such as the text or localized pattern.
This instance is immutable and unaffected by this method call.
locale
- the new locale, not nullpublic DecimalStyle getDecimalStyle()
public DateTimeFormatter withDecimalStyle(DecimalStyle decimalStyle)
This instance is immutable and unaffected by this method call.
decimalStyle
- the new DecimalStyle, not nullpublic Chronology getChronology()
This returns the override chronology, used to convert dates.
By default, a formatter has no override chronology, returning null.
See withChronology(Chronology)
for more details on overriding.
public DateTimeFormatter withChronology(Chronology chrono)
This returns a formatter with similar state to this formatter but with the override chronology set. By default, a formatter has no override chronology, returning null.
If an override is added, then any date that is formatted or parsed will be affected.
When formatting, if the temporal object contains a date, then it will
be converted to a date in the override chronology.
Whether the temporal contains a date is determined by querying the
EPOCH_DAY
field.
Any time or zone will be retained unaltered unless overridden.
If the temporal object does not contain a date, but does contain one
or more ChronoField
date fields, then a DateTimeException
is thrown. In all other cases, the override chronology is added to the temporal,
replacing any previous chronology, but without changing the date/time.
When parsing, there are two distinct cases to consider.
If a chronology has been parsed directly from the text, perhaps because
DateTimeFormatterBuilder.appendChronologyId()
was used, then
this override chronology has no effect.
If no zone has been parsed, then this override chronology will be used
to interpret the ChronoField
values into a date according to the
date resolving rules of the chronology.
This instance is immutable and unaffected by this method call.
chrono
- the new chronology, null if no overridepublic ZoneId getZone()
This returns the override zone, used to convert instants.
By default, a formatter has no override zone, returning null.
See withZone(ZoneId)
for more details on overriding.
public DateTimeFormatter withZone(ZoneId zone)
This returns a formatter with similar state to this formatter but with the override zone set. By default, a formatter has no override zone, returning null.
If an override is added, then any instant that is formatted or parsed will be affected.
When formatting, if the temporal object contains an instant, then it will
be converted to a zoned date-time using the override zone.
Whether the temporal is an instant is determined by querying the
INSTANT_SECONDS
field.
If the input has a chronology then it will be retained unless overridden.
If the input does not have a chronology, such as Instant
, then
the ISO chronology will be used.
If the temporal object does not contain an instant, but does contain
an offset then an additional check is made. If the normalized override
zone is an offset that differs from the offset of the temporal, then
a DateTimeException
is thrown. In all other cases, the override
zone is added to the temporal, replacing any previous zone, but without
changing the date/time.
When parsing, there are two distinct cases to consider.
If a zone has been parsed directly from the text, perhaps because
DateTimeFormatterBuilder.appendZoneId()
was used, then
this override zone has no effect.
If no zone has been parsed, then this override zone will be included in
the result of the parse where it can be used to build instants and date-times.
This instance is immutable and unaffected by this method call.
zone
- the new override zone, null if no overridepublic ResolverStyle getResolverStyle()
This returns the resolver style, used during the second phase of parsing
when fields are resolved into dates and times.
By default, a formatter has the SMART
resolver style.
See withResolverStyle(ResolverStyle)
for more details.
public DateTimeFormatter withResolverStyle(ResolverStyle resolverStyle)
This returns a formatter with similar state to this formatter but
with the resolver style set. By default, a formatter has the
SMART
resolver style.
Changing the resolver style only has an effect during parsing.
Parsing a text string occurs in two phases.
Phase 1 is a basic text parse according to the fields added to the builder.
Phase 2 resolves the parsed field-value pairs into date and/or time objects.
The resolver style is used to control how phase 2, resolving, happens.
See ResolverStyle
for more information on the options available.
This instance is immutable and unaffected by this method call.
resolverStyle
- the new resolver style, not nullpublic Set<TemporalField> getResolverFields()
This returns the resolver fields, used during the second phase of parsing
when fields are resolved into dates and times.
By default, a formatter has no resolver fields, and thus returns null.
See withResolverFields(Set)
for more details.
public DateTimeFormatter withResolverFields(TemporalField... resolverFields)
This returns a formatter with similar state to this formatter but with the resolver fields set. By default, a formatter has no resolver fields.
Changing the resolver fields only has an effect during parsing. Parsing a text string occurs in two phases. Phase 1 is a basic text parse according to the fields added to the builder. Phase 2 resolves the parsed field-value pairs into date and/or time objects. The resolver fields are used to filter the field-value pairs between phase 1 and 2.
This can be used to select between two or more ways that a date or time might
be resolved. For example, if the formatter consists of year, month, day-of-month
and day-of-year, then there are two ways to resolve a date.
Calling this method with the arguments YEAR
and
DAY_OF_YEAR
will ensure that the date is
resolved using the year and day-of-year, effectively meaning that the month
and day-of-month are ignored during the resolving phase.
In a similar manner, this method can be used to ignore secondary fields that
would otherwise be cross-checked. For example, if the formatter consists of year,
month, day-of-month and day-of-week, then there is only one way to resolve a
date, but the parsed value for day-of-week will be cross-checked against the
resolved date. Calling this method with the arguments YEAR
,
MONTH_OF_YEAR
and
DAY_OF_MONTH
will ensure that the date is
resolved correctly, but without any cross-check for the day-of-week.
In implementation terms, this method behaves as follows. The result of the parsing phase can be considered to be a map of field to value. The behavior of this method is to cause that map to be filtered between phase 1 and 2, removing all fields other than those specified as arguments to this method.
This instance is immutable and unaffected by this method call.
resolverFields
- the new set of resolver fields, null if no fieldspublic DateTimeFormatter withResolverFields(Set<TemporalField> resolverFields)
This returns a formatter with similar state to this formatter but with the resolver fields set. By default, a formatter has no resolver fields.
Changing the resolver fields only has an effect during parsing. Parsing a text string occurs in two phases. Phase 1 is a basic text parse according to the fields added to the builder. Phase 2 resolves the parsed field-value pairs into date and/or time objects. The resolver fields are used to filter the field-value pairs between phase 1 and 2.
This can be used to select between two or more ways that a date or time might
be resolved. For example, if the formatter consists of year, month, day-of-month
and day-of-year, then there are two ways to resolve a date.
Calling this method with the arguments YEAR
and
DAY_OF_YEAR
will ensure that the date is
resolved using the year and day-of-year, effectively meaning that the month
and day-of-month are ignored during the resolving phase.
In a similar manner, this method can be used to ignore secondary fields that
would otherwise be cross-checked. For example, if the formatter consists of year,
month, day-of-month and day-of-week, then there is only one way to resolve a
date, but the parsed value for day-of-week will be cross-checked against the
resolved date. Calling this method with the arguments YEAR
,
MONTH_OF_YEAR
and
DAY_OF_MONTH
will ensure that the date is
resolved correctly, but without any cross-check for the day-of-week.
In implementation terms, this method behaves as follows. The result of the parsing phase can be considered to be a map of field to value. The behavior of this method is to cause that map to be filtered between phase 1 and 2, removing all fields other than those specified as arguments to this method.
This instance is immutable and unaffected by this method call.
resolverFields
- the new set of resolver fields, null if no fieldspublic String format(TemporalAccessor temporal)
This formats the date-time to a String using the rules of the formatter.
temporal
- the temporal object to format, not nullDateTimeException
- if an error occurs during formattingpublic void formatTo(TemporalAccessor temporal, Appendable appendable)
Appendable
using this formatter.
This outputs the formatted date-time to the specified destination.
Appendable
is a general purpose interface that is implemented by all
key character output classes including StringBuffer
, StringBuilder
,
PrintStream
and Writer
.
Although Appendable
methods throw an IOException
, this method does not.
Instead, any IOException
is wrapped in a runtime exception.
temporal
- the temporal object to format, not nullappendable
- the appendable to format to, not nullDateTimeException
- if an error occurs during formattingpublic TemporalAccessor parse(CharSequence text)
This parses the entire text producing a temporal object.
It is typically more useful to use parse(CharSequence, TemporalQuery)
.
The result of this method is TemporalAccessor
which has been resolved,
applying basic validation checks to help ensure a valid date-time.
If the parse completes without reading the entire length of the text, or a problem occurs during parsing or merging, then an exception is thrown.
text
- the text to parse, not nullDateTimeParseException
- if unable to parse the requested resultpublic TemporalAccessor parse(CharSequence text, ParsePosition position)
This parses the text without requiring the parse to start from the beginning
of the string or finish at the end.
The result of this method is TemporalAccessor
which has been resolved,
applying basic validation checks to help ensure a valid date-time.
The text will be parsed from the specified start ParsePosition
.
The entire length of the text does not have to be parsed, the ParsePosition
will be updated with the index at the end of parsing.
The operation of this method is slightly different to similar methods using
ParsePosition
on java.text.Format
. That class will return
errors using the error index on the ParsePosition
. By contrast, this
method will throw a DateTimeParseException
if an error occurs, with
the exception containing the error index.
This change in behavior is necessary due to the increased complexity of
parsing and resolving dates/times in this API.
If the formatter parses the same field more than once with different values, the result will be an error.
text
- the text to parse, not nullposition
- the position to parse from, updated with length parsed
and the index of any error, not nullDateTimeParseException
- if unable to parse the requested resultIndexOutOfBoundsException
- if the position is invalidpublic <T> T parse(CharSequence text, TemporalQuery<T> query)
Most applications should use this method for parsing.
It parses the entire text to produce the required date-time.
The query is typically a method reference to a from(TemporalAccessor)
method.
For example:
LocalDateTime dt = parser.parse(str, LocalDateTime::from);If the parse completes without reading the entire length of the text, or a problem occurs during parsing or merging, then an exception is thrown.
T
- the type of the parsed date-timetext
- the text to parse, not nullquery
- the query defining the type to parse to, not nullDateTimeParseException
- if unable to parse the requested resultpublic TemporalAccessor parseBest(CharSequence text, TemporalQuery<?>... queries)
This parse method is convenient for use when the parser can handle optional elements.
For example, a pattern of 'uuuu-MM-dd HH.mm[ VV]' can be fully parsed to a ZonedDateTime
,
or partially parsed to a LocalDateTime
.
The queries must be specified in order, starting from the best matching full-parse option
and ending with the worst matching minimal parse option.
The query is typically a method reference to a from(TemporalAccessor)
method.
The result is associated with the first type that successfully parses.
Normally, applications will use instanceof
to check the result.
For example:
TemporalAccessor dt = parser.parseBest(str, ZonedDateTime::from, LocalDateTime::from); if (dt instanceof ZonedDateTime) { ... } else { ... }If the parse completes without reading the entire length of the text, or a problem occurs during parsing or merging, then an exception is thrown.
text
- the text to parse, not nullqueries
- the queries defining the types to attempt to parse to,
must implement TemporalAccessor
, not nullIllegalArgumentException
- if less than 2 types are specifiedDateTimeParseException
- if unable to parse the requested resultpublic TemporalAccessor parseUnresolved(CharSequence text, ParsePosition position)
Parsing is implemented as a two-phase operation.
First, the text is parsed using the layout defined by the formatter, producing
a Map
of field to value, a ZoneId
and a Chronology
.
Second, the parsed data is resolved, by validating, combining and
simplifying the various fields into more useful ones.
This method performs the parsing stage but not the resolving stage.
The result of this method is TemporalAccessor
which represents the
data as seen in the input. Values are not validated, thus parsing a date string
of '2012-00-65' would result in a temporal with three fields - year of '2012',
month of '0' and day-of-month of '65'.
The text will be parsed from the specified start ParsePosition
.
The entire length of the text does not have to be parsed, the ParsePosition
will be updated with the index at the end of parsing.
Errors are returned using the error index field of the ParsePosition
instead of DateTimeParseException
.
The returned error index will be set to an index indicative of the error.
Callers must check for errors before using the result.
If the formatter parses the same field more than once with different values, the result will be an error.
This method is intended for advanced use cases that need access to the
internal state during parsing. Typical application code should use
parse(CharSequence, TemporalQuery)
or the parse method on the target type.
text
- the text to parse, not nullposition
- the position to parse from, updated with length parsed
and the index of any error, not nullDateTimeException
- if some problem occurs during parsingIndexOutOfBoundsException
- if the position is invalidpublic Format toFormat()
java.text.Format
instance.
The returned Format
instance will format any TemporalAccessor
and parses to a resolved TemporalAccessor
.
Exceptions will follow the definitions of Format
, see those methods
for details about IllegalArgumentException
during formatting and
ParseException
or null during parsing.
The format does not support attributing of the returned format string.
public Format toFormat(TemporalQuery<?> parseQuery)
java.text.Format
instance that will
parse using the specified query.
The returned Format
instance will format any TemporalAccessor
and parses to the type specified.
The type must be one that is supported by parse(java.lang.CharSequence)
.
Exceptions will follow the definitions of Format
, see those methods
for details about IllegalArgumentException
during formatting and
ParseException
or null during parsing.
The format does not support attributing of the returned format string.
parseQuery
- the query defining the type to parse to, not null Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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