DateFormat is an abstract class for date/time formatting subclasses which
formats and parses dates or time in a language-independent manner.
The date/time formatting subclass, such as SimpleDateFormat, allows for
formatting (i.e., millis -> text), parsing (text -> millis), and
normalization. Formats/Parses a date or time, which is the standard millis
since 24:00 GMT, Jan 1, 1970
DateFormat provides many class methods for obtaining default date/time
formatters based on the default or a given loacle and a number of formatting
styles. The formatting styles include FULL, LONG, MEDIUM, and SHORT. More
detail and examples of using these styles are provided in the method
descriptions.
DateFormat helps you to format and parse dates for any locale.
Your code can be completely independent of the locale conventions for
months, days of the week, or even the calendar format: lunar vs. solar.
To format a date for the current Locale, use one of the
static factory methods:
myString = DateFormat.getDateInstance().format(myDate);
If you are formatting multiple numbers, it is
more efficient to get the format and use it multiple times so that
the system doesn't have to fetch the information about the local
language and country conventions multiple times.
DateFormat df = DateFormat.getDateInstance();
for (int i = 0; i < a.length; ++i) {
output.println(df.format(myDate[i]) + "; ");
}
To format a number for a different Locale, specify it in the
call to getDateInstance().
DateFormat df = DateFormat.getDateInstance(Locale.FRANCE);
You can use a DateFormat to parse also.
myDate = df.parse(myString);
Use getDate to get the normal date format for that country.
There are other static factory methods available.
Use getTime to get the time format for that country.
Use getDateTime to get a date and time format. You can pass in different
options to these factory methods to control the length of the
result; from SHORT to MEDIUM to LONG to FULL. The exact result depends
on the locale, but generally:
SHORT is completely numeric, such as 12.13.52 or 3:30pm
MEDIUM is longer, such as Jan 12, 1952
LONG is longer, such as January 12, 1952 or 3:30:32pm
FULL is pretty completely specified, such as
Tuesday, April 12, 1952 AD or 3:30:42pm PST.
You can also set the time zone on the format if you wish.
If you want even more control over the format or parsing,
(or want to give your users more control),
you can try casting the DateFormat you get from the factory methods
to a SimpleDateFormat. This will work for the majority
of countries; just remember to put it in a try block in case you
encounter an unusual one.
You can also use forms of the parse and format methods with
ParsePosition and FieldPosition to
allow you to
pregressively parse through pieces of a string.
align any particular field, or find out where it is for selection
on the screen.
The calendar that DateFormat uses to produce the time field values
needed to implement date/time formatting. Subclasses should initialize
this to the default calendar for the locale associated with this
DateFormat.
The number formatter that DateFormat uses to format numbers in dates
and times. Subclasses should initialize this to the default number
format for the locale associated with this DateFormat.
ERA_FIELD
public static final int ERA_FIELD
Useful constant for ERA field alignment.
Used in FieldPosition of date/time formatting.
YEAR_FIELD
public static final int YEAR_FIELD
Useful constant for YEAR field alignment.
Used in FieldPosition of date/time formatting.
MONTH_FIELD
public static final int MONTH_FIELD
Useful constant for MONTH field alignment.
Used in FieldPosition of date/time formatting.
DATE_FIELD
public static final int DATE_FIELD
Useful constant for DATE field alignment.
Used in FieldPosition of date/time formatting.
HOUR_OF_DAY1_FIELD
public static final int HOUR_OF_DAY1_FIELD
Useful constant for one-based HOUR_OF_DAY field alignment.
Used in FieldPosition of date/time formatting.
HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock.
For example, 23:59 + 01:00 results in 24:59.
HOUR_OF_DAY0_FIELD
public static final int HOUR_OF_DAY0_FIELD
Useful constant for zero-based HOUR_OF_DAY field alignment.
Used in FieldPosition of date/time formatting.
HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock.
For example, 23:59 + 01:00 results in 00:59.
MINUTE_FIELD
public static final int MINUTE_FIELD
Useful constant for MINUTE field alignment.
Used in FieldPosition of date/time formatting.
SECOND_FIELD
public static final int SECOND_FIELD
Useful constant for SECOND field alignment.
Used in FieldPosition of date/time formatting.
MILLISECOND_FIELD
public static final int MILLISECOND_FIELD
Useful constant for MILLISECOND field alignment.
Used in FieldPosition of date/time formatting.
DAY_OF_WEEK_FIELD
public static final int DAY_OF_WEEK_FIELD
Useful constant for DAY_OF_WEEK field alignment.
Used in FieldPosition of date/time formatting.
DAY_OF_YEAR_FIELD
public static final int DAY_OF_YEAR_FIELD
Useful constant for DAY_OF_YEAR field alignment.
Used in FieldPosition of date/time formatting.
DAY_OF_WEEK_IN_MONTH_FIELD
public static final int DAY_OF_WEEK_IN_MONTH_FIELD
Useful constant for DAY_OF_WEEK_IN_MONTH field alignment.
Used in FieldPosition of date/time formatting.
WEEK_OF_YEAR_FIELD
public static final int WEEK_OF_YEAR_FIELD
Useful constant for WEEK_OF_YEAR field alignment.
Used in FieldPosition of date/time formatting.
WEEK_OF_MONTH_FIELD
public static final int WEEK_OF_MONTH_FIELD
Useful constant for WEEK_OF_MONTH field alignment.
Used in FieldPosition of date/time formatting.
AM_PM_FIELD
public static final int AM_PM_FIELD
Useful constant for AM_PM field alignment.
Used in FieldPosition of date/time formatting.
HOUR1_FIELD
public static final int HOUR1_FIELD
Useful constant for one-based HOUR field alignment.
Used in FieldPosition of date/time formatting.
HOUR1_FIELD is used for the one-based 12-hour clock.
For example, 11:30 PM + 1 hour results in 12:30 AM.
HOUR0_FIELD
public static final int HOUR0_FIELD
Useful constant for zero-based HOUR field alignment.
Used in FieldPosition of date/time formatting.
HOUR0_FIELD is used for the zero-based 12-hour clock.
For example, 11:30 PM + 1 hour results in 00:30 AM.
TIMEZONE_FIELD
public static final int TIMEZONE_FIELD
Useful constant for TIMEZONE field alignment.
Used in FieldPosition of date/time formatting.
date - a Date to be formatted into a date/time string.
toAppendTo - the string buffer for the returning date/time string.
status - the formatting status. On input: an alignment field,
if desired. On output: the offsets of the alignment field. For
example, given a time text "1996.07.10 AD at 15:08:56 PDT",
if the given status.field is DateFormat.YEAR_FIELD, the offsets
status.beginIndex and status.getEndIndex will be set to 0 and 4,
respectively. Notice that if the same time field appears
more than once in a pattern, the status will be set for the first
occurence of that time field. For instance, formatting a Date to
the time string "1 PM PDT (Pacific Daylight Time)" using the pattern
"h a z (zzzz)" and the alignment field DateFormat.TIMEZONE_FIELD,
the offsets status.beginIndex and status.getEndIndex will be set to
5 and 8, respectively, for the first occurence of the timezone
pattern character 'z'.
Parse a date/time string according to the given parse position. For
example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
that is equivalent to Date(837039928046).
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).
Parameters:
text - The date/time string to be parsed
pos - 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.
the time zone associated with the calendar of DateFormat.
setLenient
public void setLenient(boolean lenient)
Specify whether or not date/time parsing is to 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.
AM_PM_FIELD
calendar
DateFormat()
clone()
getAvailableLocales()
calendar
ERA_FIELD
DateFormat
format
getTimeInstance