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Chapter 29 The java.text Package |
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29.7 java.text.DateFormat (JDK 1.1)
This class formats and parses dates and times in a locale-specific way. As an abstract class, it cannot be instantiated directly, but it provides a number of static methods that return instances of a concrete subclass which you can use to format dates in a variety of ways. The getDateInstance() methods return a DateFormat object suitable for formatting dates in either the default locale or a specified locale. A formatting style may also optionally be specified--the constants FULL, LONG, MEDIUM, SHORT, and DEFAULT specify this style. Similarly, the getTimeInstance() methods return a DateFormat object that formats and parses times, and the getDateTimeInstance() methods return a DateFormat object that formats both dates and times. These methods also optionally take a format style constant and a Locale. Finally, getInstance() returns a default DateFormat object that formats both dates and times in the SHORT format.
Once you have created a DateFormat object, you can use the setCalendar() and setTimeZone() methods if you want to format the date using a calendar or time zone other than the default.
The various format() methods convert java.util.Date objects to strings, using whatever format is encapsulated in the DateFormat object. The parse() and parseObject() methods perform the reverse operation--they parse a string formatted according to the rules of the DateFormat object and convert it into a Date object.
The DEFAULT, FULL, MEDIUM, LONG, and SHORT constants are used to specify how verbose or compact the formatted date or time should be. The remaining constants, which all end with _FIELD, specify various fields of formatted dates and times and are used with the FieldPosition object that is optionally passed to format().
public abstract class DateFormat extends Format implements Cloneable {
// Protected Constructor
protected DateFormat();
// Format Style Constants
public static final int DEFAULT;
public static final int FULL;
public static final int LONG;
public static final int MEDIUM;
public static final int SHORT;
// Date and Time Field Constants
public static final int ERA_FIELD;
public static final int YEAR_FIELD;
public static final int MONTH_FIELD;
public static final int WEEK_OF_MONTH_FIELD, WEEK_OF_YEAR_FIELD;
public static final int DATE_FIELD, DAY_OF_YEAR_FIELD;
public static final int DAY_OF_WEEK_FIELD, DAY_OF_WEEK_IN_MONTH_FIELD;
public static final int TIMEZONE_FIELD;
public static final int AM_PM_FIELD;
public static final int HOUR0_FIELD, HOUR1_FIELD;
public static final int HOUR_OF_DAY0_FIELD, HOUR_OF_DAY1_FIELD;
public static final int MINUTE_FIELD;
public static final int SECOND_FIELD;
public static final int MILLISECOND_FIELD;
// Protected Instance Variables
protected Calendar calendar;
protected NumberFormat numberFormat;
// Class Methods
public static Locale[] getAvailableLocales();
public static final DateFormat getDateInstance();
public static final DateFormat getDateInstance(int style);
public static final DateFormat getDateInstance(int style, Locale aLocale);
public static final DateFormat getDateTimeInstance();
public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle);
public static final DateFormat getDateTimeInstance(int dateStyle, int timeStyle, Locale aLocale);
public static final DateFormat getInstance();
public static final DateFormat getTimeInstance();
public static final DateFormat getTimeInstance(int style);
public static final DateFormat getTimeInstance(int style, Locale aLocale);
// Public Instance Methods
public Object clone(); // Overrides Format
public boolean equals(Object obj); // Overrides Object
public final StringBuffer format(Object obj, StringBuffer toAppendTo, FieldPosition fieldPosition); // Defines Format
public abstract StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition);
public final String format(Date date);
public Calendar getCalendar();
public NumberFormat getNumberFormat();
public TimeZone getTimeZone();
public int hashCode(); // Overrides Object
public boolean isLenient();
public Date parse(String text) throws ParseException;
public abstract Date parse(String text, ParsePosition pos);
public Object parseObject(String source, ParsePosition pos); // Defines Format
public void setCalendar(Calendar newCalendar);
public void setLenient(boolean lenient);
public void setNumberFormat(NumberFormat newNumberFormat);
public void setTimeZone(TimeZone zone);
}
Hierarchy:
Object->Format(Serializable, Cloneable)->DateFormat(Cloneable)
Extended By:
SimpleDateFormat
Returned By:
DateFormat.getDateInstance(), DateFormat.getDateTimeInstance(), DateFormat.getInstance(), DateFormat.getTimeInstance()
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| java.text.Collator (JDK 1.1) |  |
java.text.DateFormatSymbols (JDK 1.1) |
