javax.mail.internet

Class MailDateFormat

java.lang.Object

java.text.Format

java.text.DateFormat

java.text.SimpleDateFormat

javax.mail.internet.MailDateFormat

All Implemented Interfaces:

Serializable, Cloneable

public class MailDateFormat
extends SimpleDateFormat

Formats and parses date specification based on RFC 2822.

This class does not support methods that influence the format. It always formats the date based on the specification below.

3.3. Date and Time Specification

Date and time occur in several header fields. This section specifies the syntax for a full date and time specification. Though folding white space is permitted throughout the date-time specification, it is RECOMMENDED that a single space be used in each place that FWS appears (whether it is required or optional); some older implementations may not interpret other occurrences of folding white space correctly.

 date-time       =       [ day-of-week "," ] date FWS time [CFWS]

 day-of-week     =       ([FWS] day-name) / obs-day-of-week

 day-name        =       "Mon" / "Tue" / "Wed" / "Thu" /
                         "Fri" / "Sat" / "Sun"

 date            =       day month year

 year            =       4*DIGIT / obs-year

 month           =       (FWS month-name FWS) / obs-month

 month-name      =       "Jan" / "Feb" / "Mar" / "Apr" /
                         "May" / "Jun" / "Jul" / "Aug" /
                         "Sep" / "Oct" / "Nov" / "Dec"

 day             =       ([FWS] 1*2DIGIT) / obs-day

 time            =       time-of-day FWS zone

 time-of-day     =       hour ":" minute [ ":" second ]

 hour            =       2DIGIT / obs-hour

 minute          =       2DIGIT / obs-minute

 second          =       2DIGIT / obs-second

 zone            =       (( "+" / "-" ) 4DIGIT) / obs-zone
 

The day is the numeric day of the month. The year is any numeric year 1900 or later.

The time-of-day specifies the number of hours, minutes, and optionally seconds since midnight of the date indicated.

The date and time-of-day SHOULD express local time.

The zone specifies the offset from Coordinated Universal Time (UTC, formerly referred to as "Greenwich Mean Time") that the date and time-of-day represent. The "+" or "-" indicates whether the time-of-day is ahead of (i.e., east of) or behind (i.e., west of) Universal Time. The first two digits indicate the number of hours difference from Universal Time, and the last two digits indicate the number of minutes difference from Universal Time. (Hence, +hhmm means +(hh * 60 + mm) minutes, and -hhmm means -(hh * 60 + mm) minutes). The form "+0000" SHOULD be used to indicate a time zone at Universal Time. Though "-0000" also indicates Universal Time, it is used to indicate that the time was generated on a system that may be in a local time zone other than Universal Time and therefore indicates that the date-time contains no information about the local time zone.

A date-time specification MUST be semantically valid. That is, the day-of-the-week (if included) MUST be the day implied by the date, the numeric day-of-month MUST be between 1 and the number of days allowed for the specified month (in the specified year), the time-of-day MUST be in the range 00:00:00 through 23:59:60 (the number of seconds allowing for a leap second; see [STD12]), and the zone MUST be within the range -9959 through +9959.

Synchronization

Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Since:

JavaMail 1.2

Author:

Anthony Vanelverdinghe, Max Spivak

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.text.DateFormat

DateFormat.Field

Field Summary

Fields inherited from class java.text.DateFormat

AM_PM_FIELD, calendar, DATE_FIELD, DAY_OF_WEEK_FIELD, DAY_OF_WEEK_IN_MONTH_FIELD, DAY_OF_YEAR_FIELD, DEFAULT, ERA_FIELD, FULL, HOUR_OF_DAY0_FIELD, HOUR_OF_DAY1_FIELD, HOUR0_FIELD, HOUR1_FIELD, LONG, MEDIUM, MILLISECOND_FIELD, MINUTE_FIELD, MONTH_FIELD, numberFormat, SECOND_FIELD, SHORT, TIMEZONE_FIELD, WEEK_OF_MONTH_FIELD, WEEK_OF_YEAR_FIELD, YEAR_FIELD

Constructor Summary

Constructors

Constructor and Description
MailDateFormat() Create a new date format for the RFC2822 specification with lenient parsing.

Method Summary

Modifier and Type	Method and Description
StringBuffer	format(Date date, StringBuffer dateStrBuf, FieldPosition fieldPosition) Formats the given date in the format specified by RFC 2822 in the current TimeZone.
Date	parse(String text, ParsePosition pos) Parses the given date in the format specified by RFC 2822.
void	setCalendar(Calendar newCalendar) This method always throws an UnsupportedOperationException and should not be used because RFC 2822 mandates a specific calendar.
void	setNumberFormat(NumberFormat newNumberFormat) This method always throws an UnsupportedOperationException and should not be used because RFC 2822 mandates a specific number format.

Methods inherited from class java.text.SimpleDateFormat

applyLocalizedPattern, applyPattern, clone, equals, formatToCharacterIterator, get2DigitYearStart, getDateFormatSymbols, hashCode, set2DigitYearStart, setDateFormatSymbols, toLocalizedPattern, toPattern

Methods inherited from class java.text.DateFormat

format, format, getAvailableLocales, getCalendar, getDateInstance, getDateInstance, getDateInstance, getDateTimeInstance, getDateTimeInstance, getDateTimeInstance, getInstance, getNumberFormat, getTimeInstance, getTimeInstance, getTimeInstance, getTimeZone, isLenient, parse, parseObject, setLenient, setTimeZone

Methods inherited from class java.text.Format

format, parseObject

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MailDateFormat

public MailDateFormat()

Create a new date format for the RFC2822 specification with lenient parsing.

Method Detail

format

public StringBuffer format(Date date,
                           StringBuffer dateStrBuf,
                           FieldPosition fieldPosition)

Formats the given date in the format specified by RFC 2822 in the current TimeZone.

Overrides:

format in class SimpleDateFormat

Parameters:

date - the Date object

dateStrBuf - the formatted string

fieldPosition - the current field position

Returns:

StringBuffer the formatted String

Since:

JavaMail 1.2

parse

public Date parse(String text,
                  ParsePosition pos)

Parses the given date in the format specified by RFC 2822.

• With strict parsing, obs-* tokens are unsupported. Lenient parsing supports obs-year and obs-zone, with the exception of the 1-character military time zones.
• The optional CFWS token at the end is not parsed.
• RFC 2822 specifies that a zone of "-0000" indicates that the date-time contains no information about the local time zone. This class uses the UTC time zone in this case.

Overrides:

parse in class SimpleDateFormat

Parameters:

text - the formatted date to be parsed

pos - the current parse position

Returns:

Date the parsed date. In case of error, returns null.

Since:

JavaMail 1.2

setCalendar

public void setCalendar(Calendar newCalendar)

This method always throws an UnsupportedOperationException and should not be used because RFC 2822 mandates a specific calendar.

Overrides:

setCalendar in class DateFormat

Throws:

UnsupportedOperationException - if this method is invoked

setNumberFormat

public void setNumberFormat(NumberFormat newNumberFormat)

This method always throws an UnsupportedOperationException and should not be used because RFC 2822 mandates a specific number format.

Overrides:

setNumberFormat in class DateFormat

Throws:

UnsupportedOperationException - if this method is invoked