java.lang.Object | ||
↳ | java.text.Format | |
↳ | java.text.DateFormat |
Known Direct Subclasses |
Formats or parses dates and times.
This class provides factories for obtaining instances configured for a specific locale.
The most common subclass is
SimpleDateFormat
.
This code:
DateFormat[] formats = new DateFormat[] { DateFormat.getDateInstance(), DateFormat.getDateTimeInstance(), DateFormat.getTimeInstance(), }; for (DateFormat df : formats) { System.out.println(df.format(new Date(0))); df.setTimeZone(TimeZone.getTimeZone("UTC")); System.out.println(df.format(new Date(0))); }
Produces this output when run on an
en_US
device in the America/Los_Angeles time zone:
Dec 31, 1969 Jan 1, 1970 Dec 31, 1969 4:00:00 PM Jan 1, 1970 12:00:00 AM 4:00:00 PM 12:00:00 AMAnd will produce similarly appropriate localized human-readable output on any user's system. Notice how the same point in time when formatted can appear to be a different time when rendered for a different time zone. This is one reason why formatting should be left until the data will only be presented to a human. Machines should interchange "Unix time" integers.
Nested Classes | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
|
DateFormat.Field |
The instances of this inner class are used as attribute keys and values
in
AttributedCharacterIterator
that the
formatToCharacterIterator(Object)
method returns.
|
Constants | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
int | AM_PM_FIELD |
FieldPosition selector for 'a' field alignment, corresponds to the
AM_PM
field.
|
|||||||||
int | DATE_FIELD |
The
FieldPosition
selector for 'd' field alignment, corresponds
to the
DATE
field.
|
|||||||||
int | DAY_OF_WEEK_FIELD |
FieldPosition selector for 'E' field alignment, corresponds to the
DAY_OF_WEEK
field.
|
|||||||||
int | DAY_OF_WEEK_IN_MONTH_FIELD |
FieldPosition selector for 'F' field alignment, corresponds to the
DAY_OF_WEEK_IN_MONTH
field.
|
|||||||||
int | DAY_OF_YEAR_FIELD |
FieldPosition selector for 'D' field alignment, corresponds to the
DAY_OF_YEAR
field.
|
|||||||||
int | DEFAULT | The format style constant defining the default format style. | |||||||||
int | ERA_FIELD |
The
FieldPosition
selector for 'G' field alignment, corresponds
to the
ERA
field.
|
|||||||||
int | FULL | The format style constant defining the full style. | |||||||||
int | HOUR0_FIELD |
The
FieldPosition
selector for 'K' field alignment, corresponding to the
HOUR
field.
|
|||||||||
int | HOUR1_FIELD |
FieldPosition selector for 'h' field alignment, corresponding to the
HOUR
field.
|
|||||||||
int | HOUR_OF_DAY0_FIELD |
The
FieldPosition
selector for 'H' field alignment, corresponds
to the
HOUR_OF_DAY
field.
|
|||||||||
int | HOUR_OF_DAY1_FIELD |
The
FieldPosition
selector for 'k' field alignment, corresponds
to the
HOUR_OF_DAY
field.
|
|||||||||
int | LONG | The format style constant defining the long style. | |||||||||
int | MEDIUM | The format style constant defining the medium style. | |||||||||
int | MILLISECOND_FIELD |
FieldPosition selector for 'S' field alignment, corresponds to the
MILLISECOND
field.
|
|||||||||
int | MINUTE_FIELD |
FieldPosition selector for 'm' field alignment, corresponds to the
MINUTE
field.
|
|||||||||
int | MONTH_FIELD |
The
FieldPosition
selector for 'M' field alignment, corresponds
to the
MONTH
field.
|
|||||||||
int | SECOND_FIELD |
FieldPosition selector for 's' field alignment, corresponds to the
SECOND
field.
|
|||||||||
int | SHORT | The format style constant defining the short style. | |||||||||
int | TIMEZONE_FIELD |
The
FieldPosition
selector for 'z' field alignment, corresponds
to the
ZONE_OFFSET
and
DST_OFFSET
fields.
|
|||||||||
int | WEEK_OF_MONTH_FIELD |
FieldPosition selector for 'W' field alignment, corresponds to the
WEEK_OF_MONTH
field.
|
|||||||||
int | WEEK_OF_YEAR_FIELD |
FieldPosition selector for 'w' field alignment, corresponds to the
WEEK_OF_YEAR
field.
|
|||||||||
int | YEAR_FIELD |
The
FieldPosition
selector for 'y' field alignment, corresponds
to the
YEAR
field.
|
Fields | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
|
calendar |
The calendar that this
DateFormat
uses to format a number
representing a date.
|
|||||||||
|
numberFormat | The number format used to format a number. |
Protected Constructors | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
|
Constructs a new instance of
DateFormat
.
|
Public Methods | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
|
Returns a new instance of
DateFormat
with the same properties.
|
||||||||||
|
Compares this date format with the specified object and indicates if they
are equal.
|
||||||||||
|
Formats the specified date as a string using the pattern of this date
format and appends the string to the specified string buffer.
|
||||||||||
|
Formats the specified object as a string using the pattern of this date
format and appends the string to the specified string buffer.
|
||||||||||
|
Formats the specified date using the rules of this date format.
|
||||||||||
|
Returns an array of locales for which custom
DateFormat
instances
are available.
|
||||||||||
|
Returns the calendar used by this
DateFormat
.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates in
the specified style for the user's default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates in
the specified style for the specified locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates in
the DEFAULT style for the default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates
and time values in the specified styles for the specified locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing of both
dates and time values in the manner appropriate for the user's default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates
and time values in the DEFAULT style for the default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing dates
and times in the SHORT style for the default locale.
|
||||||||||
|
Returns the
NumberFormat
used by this
DateFormat
.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing time
values in the specified style for the user's default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing time
values in the DEFAULT style for the default locale.
|
||||||||||
|
Returns a
DateFormat
instance for formatting and parsing time
values in the specified style for the specified locale.
|
||||||||||
|
Returns the time zone of this date format's calendar.
|
||||||||||
|
Returns an integer hash code for this object.
|
||||||||||
|
Indicates whether the calendar used by this date format is lenient.
|
||||||||||
|
Parses a date from the specified string using the rules of this date
format.
|
||||||||||
|
Parses a date from the specified string starting at the index specified
by
position
.
|
||||||||||
|
Parses a date from the specified string starting at the index specified
by
position
.
|
||||||||||
|
Sets the calendar used by this date format.
|
||||||||||
|
Specifies whether or not date/time parsing shall be lenient.
|
||||||||||
|
Sets the
NumberFormat
used by this date format.
|
||||||||||
|
Sets the time zone of the calendar used by this date format.
|
[Expand]
Inherited Methods
|
|||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
From class
java.text.Format
|
|||||||||||
From class
java.lang.Object
|
FieldPosition selector for 'a' field alignment, corresponds to the
AM_PM
field.
The
FieldPosition
selector for 'd' field alignment, corresponds
to the
DATE
field.
FieldPosition selector for 'E' field alignment, corresponds to the
DAY_OF_WEEK
field.
FieldPosition selector for 'F' field alignment, corresponds to the
DAY_OF_WEEK_IN_MONTH
field.
FieldPosition selector for 'D' field alignment, corresponds to the
DAY_OF_YEAR
field.
The format style constant defining the default format style. The default is MEDIUM.
The
FieldPosition
selector for 'G' field alignment, corresponds
to the
ERA
field.
The format style constant defining the full style.
The
FieldPosition
selector for 'K' field alignment, corresponding to the
HOUR
field.
FieldPosition selector for 'h' field alignment, corresponding to the
HOUR
field.
The
FieldPosition
selector for 'H' field alignment, corresponds
to the
HOUR_OF_DAY
field.
HOUR_OF_DAY0_FIELD
is
used for the zero-based 24-hour clock. For example, 23:59 + 01:00 results
in 00:59.
The
FieldPosition
selector for 'k' field alignment, corresponds
to the
HOUR_OF_DAY
field.
HOUR_OF_DAY1_FIELD
is
used for the one-based 24-hour clock. For example, 23:59 + 01:00 results
in 24:59.
The format style constant defining the long style.
The format style constant defining the medium style.
FieldPosition selector for 'S' field alignment, corresponds to the
MILLISECOND
field.
FieldPosition selector for 'm' field alignment, corresponds to the
MINUTE
field.
The
FieldPosition
selector for 'M' field alignment, corresponds
to the
MONTH
field.
FieldPosition selector for 's' field alignment, corresponds to the
SECOND
field.
The format style constant defining the short style.
The
FieldPosition
selector for 'z' field alignment, corresponds
to the
ZONE_OFFSET
and
DST_OFFSET
fields.
FieldPosition selector for 'W' field alignment, corresponds to the
WEEK_OF_MONTH
field.
FieldPosition selector for 'w' field alignment, corresponds to the
WEEK_OF_YEAR
field.
The
FieldPosition
selector for 'y' field alignment, corresponds
to the
YEAR
field.
The calendar that this
DateFormat
uses to format a number
representing a date.
Returns a new instance of
DateFormat
with the same properties.
Compares this date format with the specified object and indicates if they are equal.
object | the object to compare with this date format. |
---|
true
if
object
is a
DateFormat
object and
it has the same properties as this date format;
false
otherwise.
Formats the specified date as a string using the pattern of this date format and appends the string to the specified string buffer.
If the
field
member of
field
contains a value specifying
a format field, then its
beginIndex
and
endIndex
members
will be updated with the position of the first occurrence of this field
in the formatted text.
date | the date to format. |
---|---|
buffer | the target string buffer to append the formatted date/time to. |
field | on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text. |
Formats the specified object as a string using the pattern of this date format and appends the string to the specified string buffer.
If the
field
member of
field
contains a value specifying
a format field, then its
beginIndex
and
endIndex
members
will be updated with the position of the first occurrence of this field
in the formatted text.
object |
the source object to format, must be a
Date
or a
Number
. If
object
is a number then a date is
constructed using the
longValue()
of the number.
|
---|---|
buffer | the target string buffer to append the formatted date/time to. |
field | on input: an optional alignment field; on output: the offsets of the alignment field in the formatted text. |
IllegalArgumentException |
if
object
is neither a
Date
nor a
Number
instance.
|
---|
Formats the specified date using the rules of this date format.
date | the date to format. |
---|
Returns an array of locales for which custom
DateFormat
instances
are available.
Note that Android does not support user-supplied locale service providers.
Returns the calendar used by this
DateFormat
.
Returns a
DateFormat
instance for formatting and parsing dates in
the specified style for the user's default locale.
See "
Be wary of the default locale
".
style | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|
DateFormat
instance for
style
and the default
locale.
IllegalArgumentException |
if
style
is not one of SHORT, MEDIUM, LONG, FULL, or
DEFAULT.
|
---|
Returns a
DateFormat
instance for formatting and parsing dates in
the specified style for the specified locale.
style | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|---|
locale | the locale. |
DateFormat
instance for
style
and
locale
.
IllegalArgumentException |
if
style
is not one of SHORT, MEDIUM, LONG, FULL, or
DEFAULT.
|
---|
Returns a
DateFormat
instance for formatting and parsing dates in
the DEFAULT style for the default locale.
DateFormat
instance for the default style and locale.
Returns a
DateFormat
instance for formatting and parsing dates
and time values in the specified styles for the specified locale.
dateStyle | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|---|
timeStyle | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
locale | the locale. |
DateFormat
instance for
dateStyle
,
timeStyle
and
locale
.
IllegalArgumentException |
if
dateStyle
or
timeStyle
is not one of
SHORT, MEDIUM, LONG, FULL, or DEFAULT.
|
---|
Returns a
DateFormat
instance for formatting and parsing of both
dates and time values in the manner appropriate for the user's default locale.
See "
Be wary of the default locale
".
dateStyle | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|---|
timeStyle | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
DateFormat
instance for
dateStyle
,
timeStyle
and the default locale.
IllegalArgumentException |
if
dateStyle
or
timeStyle
is not one of
SHORT, MEDIUM, LONG, FULL, or DEFAULT.
|
---|
Returns a
DateFormat
instance for formatting and parsing dates
and time values in the DEFAULT style for the default locale.
DateFormat
instance for the default style and locale.
Returns a
DateFormat
instance for formatting and parsing dates
and times in the SHORT style for the default locale.
DateFormat
instance for the SHORT style and default
locale.
Returns the
NumberFormat
used by this
DateFormat
.
NumberFormat
used by this date format.
Returns a
DateFormat
instance for formatting and parsing time
values in the specified style for the user's default locale.
See "
Be wary of the default locale
".
style | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|
DateFormat
instance for
style
and the default
locale.
IllegalArgumentException |
if
style
is not one of SHORT, MEDIUM, LONG, FULL, or
DEFAULT.
|
---|
Returns a
DateFormat
instance for formatting and parsing time
values in the DEFAULT style for the default locale.
DateFormat
instance for the default style and locale.
Returns a
DateFormat
instance for formatting and parsing time
values in the specified style for the specified locale.
style | one of SHORT, MEDIUM, LONG, FULL, or DEFAULT. |
---|---|
locale | the locale. |
DateFormat
instance for
style
and
locale
.
IllegalArgumentException |
if
style
is not one of SHORT, MEDIUM, LONG, FULL, or
DEFAULT.
|
---|
Returns the time zone of this date format's calendar.
Returns an integer hash code for this object. By contract, any two
objects for which
equals(Object)
returns
true
must return
the same hash code value. This means that subclasses of
Object
usually override both methods or neither method.
Note that hash values must not change over time unless information used in equals comparisons also changes.
See
Writing a correct
hashCode
method
if you intend implementing your own
hashCode
method.
Indicates whether the calendar used by this date format is lenient.
true
if the calendar is lenient;
false
otherwise.
Parses a date from the specified string using the rules of this date format.
string | the string to parse. |
---|
Date
resulting from the parsing.
ParseException | if an error occurs during parsing. |
---|
Parses a date from the specified string starting at the index specified
by
position
. If the string is successfully parsed then the index
of the
ParsePosition
is updated to the index following the parsed
text. On error, the index is unchanged and the error index of
ParsePosition
is set to the index where the error occurred.
By default, parsing is lenient: If the input is not in the form used by
this object's format method but can still be parsed as a date, then the
parse succeeds. Clients may insist on strict adherence to the format by
calling
setLenient(false)
.
string | the string to parse. |
---|---|
position |
input/output parameter, specifies the start index in
string
from where to start parsing. If parsing is successful,
it is updated with the index following the parsed text; on
error, the index is unchanged and the error index is set to
the index where the error occurred.
|
null
if there is an
error.
Parses a date from the specified string starting at the index specified
by
position
. If the string is successfully parsed then the index
of the
ParsePosition
is updated to the index following the parsed
text. On error, the index is unchanged and the error index of
ParsePosition
is set to the index where the error occurred.
By default, parsing is lenient: If the input is not in the form used by
this object's format method but can still be parsed as a date, then the
parse succeeds. Clients may insist on strict adherence to the format by
calling
setLenient(false)
.
string | the string to parse. |
---|---|
position |
input/output parameter, specifies the start index in
string
from where to start parsing. If parsing is
successful, it is updated with the index following the parsed
text; on error, the index is unchanged and the error index
is set to the index where the error occurred.
|
null
if there is
an error.
Sets the calendar used by this date format.
cal | the new calendar. |
---|
Specifies whether or not date/time parsing shall be lenient. With lenient parsing, the parser may use heuristics to interpret inputs that do not precisely match this object's format. With strict parsing, inputs must match this object's format.
value |
true
to set the calendar to be lenient,
false
otherwise.
|
---|
Sets the
NumberFormat
used by this date format.
format | the new number format. |
---|
Sets the time zone of the calendar used by this date format.
timezone | the new time zone. |
---|