public abstract class DateFormat extends Format implements Cloneable
Date
object or
as the milliseconds since January 1, 1970, 00:00:00 GMT.
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:
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
Format
,
NumberFormat
,
SimpleDateFormat
,
Calendar
,
GregorianCalendar
,
TimeZone
Modifier and Type | Field and Description |
---|---|
static int |
AM_PM_FIELD
Useful constant for AM_PM field alignment.
|
protected Calendar |
calendar
The calendar that DateFormat uses to produce the time field values
needed to implement date/time formatting.
|
static int |
DATE_FIELD
Useful constant for DATE field alignment.
|
static int |
DAY_OF_WEEK_FIELD
Useful constant for DAY_OF_WEEK field alignment.
|
static int |
DAY_OF_WEEK_IN_MONTH_FIELD
Useful constant for DAY_OF_WEEK_IN_MONTH field alignment.
|
static int |
DAY_OF_YEAR_FIELD
Useful constant for DAY_OF_YEAR field alignment.
|
static int |
DEFAULT
Constant for default style pattern.
|
static int |
ERA_FIELD
Useful constant for ERA field alignment.
|
static int |
FULL
Constant for full style pattern.
|
static int |
HOUR_OF_DAY0_FIELD
Useful constant for zero-based HOUR_OF_DAY field alignment.
|
static int |
HOUR_OF_DAY1_FIELD
Useful constant for one-based HOUR_OF_DAY field alignment.
|
static int |
HOUR0_FIELD
Useful constant for zero-based HOUR field alignment.
|
static int |
HOUR1_FIELD
Useful constant for one-based HOUR field alignment.
|
static int |
LONG
Constant for long style pattern.
|
static int |
MEDIUM
Constant for medium style pattern.
|
static int |
MILLISECOND_FIELD
Useful constant for MILLISECOND field alignment.
|
static int |
MINUTE_FIELD
Useful constant for MINUTE field alignment.
|
static int |
MONTH_FIELD
Useful constant for MONTH field alignment.
|
protected NumberFormat |
numberFormat
The number formatter that DateFormat uses to format numbers in dates
and times.
|
static int |
SECOND_FIELD
Useful constant for SECOND field alignment.
|
static int |
SHORT
Constant for short style pattern.
|
static int |
TIMEZONE_FIELD
Useful constant for TIMEZONE field alignment.
|
static int |
WEEK_OF_MONTH_FIELD
Useful constant for WEEK_OF_MONTH field alignment.
|
static int |
WEEK_OF_YEAR_FIELD
Useful constant for WEEK_OF_YEAR field alignment.
|
static int |
YEAR_FIELD
Useful constant for YEAR field alignment.
|
Modifier | Constructor and Description |
---|---|
protected |
DateFormat()
DateFormat
|
Modifier and Type | Method and Description |
---|---|
Object |
clone()
Overrides Cloneable.
|
boolean |
equals(Object obj)
Overrides equals
|
String |
format(Date date)
Formats a Date into a date/time string.
|
abstract StringBuffer |
format(Date date,
StringBuffer toAppendTo,
FieldPosition fieldPosition)
Formats a Date into a date/time string.
|
StringBuffer |
format(Object obj,
StringBuffer toAppendTo,
FieldPosition fieldPosition)
Overrides Format.
|
static Locale[] |
getAvailableLocales()
Gets the set of locales for which DateFormats are installed.
|
Calendar |
getCalendar()
Gets the calendar associated with this date/time formatter.
|
static DateFormat |
getDateInstance()
Gets the date formatter with the default formatting style
for the default locale.
|
static DateFormat |
getDateInstance(int style)
Gets the date formatter with the given formatting style
for the default locale.
|
static DateFormat |
getDateInstance(int style,
Locale aLocale)
Gets the date formatter with the given formatting style
for the given locale.
|
static DateFormat |
getDateTimeInstance()
Gets the date/time formatter with the default formatting style
for the default locale.
|
static DateFormat |
getDateTimeInstance(int dateStyle,
int timeStyle)
Gets the date/time formatter with the given date and time
formatting styles for the default locale.
|
static DateFormat |
getDateTimeInstance(int dateStyle,
int timeStyle,
Locale aLocale)
Gets the date/time formatter with the given formatting styles
for the given locale.
|
static DateFormat |
getInstance()
Get a default date/time formatter that uses the SHORT style for both the
date and the time.
|
NumberFormat |
getNumberFormat()
Gets the number formatter which this date/time formatter uses to
format and parse a time.
|
static DateFormat |
getTimeInstance()
Gets the time formatter with the default formatting style
for the default locale.
|
static DateFormat |
getTimeInstance(int style)
Gets the time formatter with the given formatting style
for the default locale.
|
static DateFormat |
getTimeInstance(int style,
Locale aLocale)
Gets the time formatter with the given formatting style
for the given locale.
|
TimeZone |
getTimeZone()
Gets the time zone.
|
int |
hashCode()
Overrides hashCode
|
boolean |
isLenient()
Tell whether date/time parsing is to be lenient.
|
Date |
parse(String text)
Parse a date/time string.
|
abstract Date |
parse(String text,
ParsePosition pos)
Parse a date/time string according to the given parse position.
|
Object |
parseObject(String source,
ParsePosition pos)
Parse a date/time string into an Object.
|
void |
setCalendar(Calendar newCalendar)
Set the calendar to be used by this date format.
|
void |
setLenient(boolean lenient)
Specify whether or not date/time parsing is to be lenient.
|
void |
setNumberFormat(NumberFormat newNumberFormat)
Allows you to set the number formatter.
|
void |
setTimeZone(TimeZone zone)
Sets the time zone for the calendar of this DateFormat object.
|
format, parseObject
protected Calendar calendar
protected NumberFormat numberFormat
public static final int ERA_FIELD
public static final int YEAR_FIELD
public static final int MONTH_FIELD
public static final int DATE_FIELD
public static final int HOUR_OF_DAY1_FIELD
public static final int HOUR_OF_DAY0_FIELD
public static final int MINUTE_FIELD
public static final int SECOND_FIELD
public static final int MILLISECOND_FIELD
public static final int DAY_OF_WEEK_FIELD
public static final int DAY_OF_YEAR_FIELD
public static final int DAY_OF_WEEK_IN_MONTH_FIELD
public static final int WEEK_OF_YEAR_FIELD
public static final int WEEK_OF_MONTH_FIELD
public static final int AM_PM_FIELD
public static final int HOUR1_FIELD
public static final int HOUR0_FIELD
public static final int TIMEZONE_FIELD
public static final int FULL
public static final int LONG
public static final int MEDIUM
public static final int SHORT
public static final int DEFAULT
public final StringBuffer format(Object obj, StringBuffer toAppendTo, FieldPosition fieldPosition)
public abstract StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition)
date
- a Date to be formatted into a date/time string.toAppendTo
- the string buffer for the returning date/time string.fieldPosition
- ?public final String format(Date date)
date
- the time value to be formatted into a time string.public Date parse(String text) throws ParseException
text
- ?ParseException
- If the given string cannot be parsed as a date.parse(String, ParsePosition)
public abstract Date parse(String text, ParsePosition pos)
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).
text
- The date/time string to be parsedpos
- 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.setLenient(boolean)
public Object parseObject(String source, ParsePosition pos)
parseObject
in class Format
pos
- positionsource
- ?parse(String, ParsePosition)
public static final DateFormat getTimeInstance()
public static final DateFormat getTimeInstance(int style)
style
- the given formatting style. For example,
SHORT for "h:mm a" in the US locale.public static final DateFormat getTimeInstance(int style, Locale aLocale)
style
- the given formatting style. For example,
SHORT for "h:mm a" in the US locale.aLocale
- the given locale.public static final DateFormat getDateInstance()
public static final DateFormat getDateInstance(int style)
style
- the given formatting style. For example,
SHORT for "M/d/yy" in the US locale.public static final DateFormat getDateInstance(int style, Locale aLocale)
style
- the given formatting style. For example,
SHORT for "M/d/yy" in the US locale.aLocale
- the given locale.public static final DateFormat getDateTimeInstance()
public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle)
dateStyle
- the given date formatting style. For example,
SHORT for "M/d/yy" in the US locale.timeStyle
- the given time formatting style. For example,
SHORT for "h:mm a" in the US locale.public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle, Locale aLocale)
dateStyle
- the given date formatting style.timeStyle
- the given time formatting style.aLocale
- the given locale.public static final DateFormat getInstance()
public static Locale[] getAvailableLocales()
public void setCalendar(Calendar newCalendar)
newCalendar
- ?public Calendar getCalendar()
public void setNumberFormat(NumberFormat newNumberFormat)
newNumberFormat
- the given new NumberFormat.public NumberFormat getNumberFormat()
public void setTimeZone(TimeZone zone)
zone
- the given new time zone.public TimeZone getTimeZone()
public void setLenient(boolean lenient)
lenient
- ?Calendar.setLenient(boolean)
public boolean isLenient()
public int hashCode()
hashCode
in class Object
Object.equals(java.lang.Object)
,
Hashtable
public boolean equals(Object obj)
equals
in class Object
obj
- the reference object with which to compare.true
if this object is the same as the obj
argument; false
otherwise.Boolean.hashCode()
,
Hashtable