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Class XMLGregorianCalendar

java.lang.Object

javax.xml.datatype.XMLGregorianCalendar

All Implemented Interfaces:: Cloneable

public abstract class XMLGregorianCalendar extends Object implements Cloneable

Representation for W3C XML Schema 1.0 date/time datatypes. Specifically, these date/time datatypes are DatatypeConstants.DATETIME, DatatypeConstants.TIME, DatatypeConstants.DATE, DatatypeConstants.GYEARMONTH, DatatypeConstants.GMONTHDAY, DatatypeConstants.GYEAR, DatatypeConstants.GMONTH, and DatatypeConstants.GDAY defined in the XML Namespace "http://www.w3.org/2001/XMLSchema". These datatypes are normatively defined in W3C XML Schema 1.0 Part 2, Section 3.2.7-14.

The table below defines the mapping between XML Schema 1.0 date/time datatype fields and this class' fields. It also summarizes the value constraints for the date and time fields defined in W3C XML Schema 1.0 Part 2, Appendix D, ISO 8601 Date and Time Formats.

Date/Time Datatype Field Mapping Between XML Schema 1.0 and Java Representation
XML Schema 1.0 datatype field	Related XMLGregorianCalendar Accessor(s)	Value Range
year	`getYear()` + `getEon()` or `getEonAndYear()`	`getYear()` is a value between -(10^9-1) to (10^9)-1 or `DatatypeConstants.FIELD_UNDEFINED`. `getEon()` is high order year value in billion of years. `getEon()` has values greater than or equal to (10^9) or less than or equal to -(10^9). A value of null indicates field is undefined. Given that XML Schema 1.0 errata states that the year zero will be a valid lexical value in a future version of XML Schema, this class allows the year field to be set to zero. Otherwise, the year field value is handled exactly as described in the errata and [ISO-8601-1988]. Note that W3C XML Schema 1.0 validation does not allow for the year field to have a value of zero.
month	`getMonth()`	1 to 12 or `DatatypeConstants.FIELD_UNDEFINED`
day	`getDay()`	Independent of month, max range is 1 to 31 or `DatatypeConstants.FIELD_UNDEFINED`. The normative value constraint stated relative to month field's value is in W3C XML Schema 1.0 Part 2, Appendix D.
hour	`getHour()`	0 to 23 or `DatatypeConstants.FIELD_UNDEFINED`. An hour value of 24 is allowed to be set in the lexical space provided the minute and second field values are zero. However, an hour value of 24 is not allowed in value space and will be transformed to represent the value of the first instance of the following day as per XML Schema Part 2: Datatypes Second Edition, 3.2 Primitive datatypes.
minute	`getMinute()`	0 to 59 or `DatatypeConstants.FIELD_UNDEFINED`
second	`getSecond()` + `getMillisecond()`/1000 or `getSecond()` + `getFractionalSecond()`	`getSecond()` from 0 to 60 or `DatatypeConstants.FIELD_UNDEFINED`. (Note: 60 only allowable for leap second.) `getFractionalSecond()` allows for infinite precision over the range from 0.0 to 1.0 when the `getSecond()` is defined. `FractionalSecond` is optional and has a value of `null` when it is undefined. `getMillisecond()` is the convenience millisecond precision of value of `getFractionalSecond()`.
timezone	`getTimezone()`	Number of minutes or `DatatypeConstants.FIELD_UNDEFINED`. Value range from -14 hours (-14 * 60 minutes) to 14 hours (14 * 60 minutes).

All maximum value space constraints listed for the fields in the table above are checked by factory methods, DatatypeFactory, setter methods and parse methods of this class. IllegalArgumentException is thrown when a parameter's value is outside the value constraint for the field or if the composite values constitute an invalid XMLGregorianCalendar instance (for example, if the 31st of June is specified).

The following operations are defined for this class:

accessors/mutators for independent date/time fields
conversion between this class and W3C XML Schema 1.0 lexical representation, toString(), DatatypeFactory.newXMLGregorianCalendar(String lexicalRepresentation)
conversion between this class and GregorianCalendar, toGregorianCalendar(java.util.TimeZone timezone, java.util.Locale aLocale, XMLGregorianCalendar defaults), DatatypeFactory
partial order relation comparator method, compare(XMLGregorianCalendar xmlGregorianCalendar)
equals(Object) defined relative to compare(XMLGregorianCalendar xmlGregorianCalendar).
addition operation with Duration instance as defined in W3C XML Schema 1.0 Part 2, Appendix E, Adding durations to dateTimes.

Since:

1.5

See Also:

Constructor Summary

Constructor	Description
`XMLGregorianCalendar()`	Default no-arg constructor.

Method Summary

Modifier and Type	Method	Description
`abstract void`	`add(Duration duration)`	Add `duration` to this instance.
`abstract void`	`clear()`	Unset all fields to undefined.
`abstract Object`	`clone()`	Creates and returns a copy of this object.
`abstract int`	`compare(XMLGregorianCalendar xmlGregorianCalendar)`	Compare two instances of W3C XML Schema 1.0 date/time datatypes according to partial order relation defined in W3C XML Schema 1.0 Part 2, Section 3.2.7.3, Order relation on dateTime.
`boolean`	`equals(Object obj)`	Compares this calendar to the specified object.
`abstract int`	`getDay()`	Returns the day of month or `DatatypeConstants.FIELD_UNDEFINED`.
`abstract BigInteger`	`getEon()`	Returns the high order component for XML Schema 1.0 dateTime datatype field for `year`.
`abstract BigInteger`	`getEonAndYear()`	Returns the XML Schema 1.0 dateTime datatype field for `year`.
`abstract BigDecimal`	`getFractionalSecond()`	Returns fractional seconds.
`abstract int`	`getHour()`	Returns the hour of day or `DatatypeConstants.FIELD_UNDEFINED` if this field is not defined.
`int`	`getMillisecond()`	Returns the millisecond precision of `getFractionalSecond()`.
`abstract int`	`getMinute()`	Returns the minute of hour or `DatatypeConstants.FIELD_UNDEFINED` if this field is not defined.
`abstract int`	`getMonth()`	Returns the month of this calendar or `DatatypeConstants.FIELD_UNDEFINED`.
`abstract int`	`getSecond()`	Returns the second of minute or `DatatypeConstants.FIELD_UNDEFINED` if this field is not defined.
`abstract int`	`getTimezone()`	Returns the Timezone offset in minutes or `DatatypeConstants.FIELD_UNDEFINED` if this optional field is not defined.
`abstract TimeZone`	`getTimeZone(int defaultZoneoffset)`	Returns a `java.util.TimeZone` for this class.
`abstract QName`	`getXMLSchemaType()`	Return the name of the XML Schema date/time type that this instance maps to.
`abstract int`	`getYear()`	Returns the low order component for XML Schema 1.0 dateTime datatype field for `year` or `DatatypeConstants.FIELD_UNDEFINED`.
`int`	`hashCode()`	Returns a hash code consistent with the definition of the equals method.
`abstract boolean`	`isValid()`	Validate instance by `getXMLSchemaType()` constraints.
`abstract XMLGregorianCalendar`	`normalize()`	Normalize this instance to UTC.
`abstract void`	`reset()`	Reset this `XMLGregorianCalendar` to its original values.
`abstract void`	`setDay(int day)`	Set days in month.
`abstract void`	`setFractionalSecond(BigDecimal fractional)`	Set fractional seconds.
`abstract void`	`setHour(int hour)`	Set hours.
`abstract void`	`setMillisecond(int millisecond)`	Set milliseconds.
`abstract void`	`setMinute(int minute)`	Set minutes.
`abstract void`	`setMonth(int month)`	Set month.
`abstract void`	`setSecond(int second)`	Set seconds.
`void`	`setTime(int hour, int minute, int second)`	Set time as one unit.
`void`	`setTime(int hour, int minute, int second, int millisecond)`	Set time as one unit, including optional milliseconds.
`void`	`setTime(int hour, int minute, int second, BigDecimal fractional)`	Set time as one unit, including the optional infinite precision fractional seconds.
`abstract void`	`setTimezone(int offset)`	Set the number of minutes in the timezone offset.
`abstract void`	`setYear(int year)`	Set year of XSD `dateTime` year field.
`abstract void`	`setYear(BigInteger year)`	Set low and high order component of XSD `dateTime` year field.
`abstract GregorianCalendar`	`toGregorianCalendar()`	Convert this `XMLGregorianCalendar` to a `GregorianCalendar`.
`abstract GregorianCalendar`	`toGregorianCalendar(TimeZone timezone, Locale aLocale, XMLGregorianCalendar defaults)`	Convert this `XMLGregorianCalendar` along with provided parameters to a `GregorianCalendar` instance.
`String`	`toString()`	Returns a `String` representation of this `XMLGregorianCalendar` `Object`.
`abstract String`	`toXMLFormat()`	Return the lexical representation of `this` instance.

Methods declared in class java.lang.Object

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

Constructor Details

XMLGregorianCalendar

public XMLGregorianCalendar()

Default no-arg constructor.

Note: Always use the DatatypeFactory to construct an instance of XMLGregorianCalendar. The constructor on this class cannot be guaranteed to produce an object with a consistent state and may be removed in the future.

Method Details

clear

public abstract void clear()

Unset all fields to undefined.

Set all int fields to DatatypeConstants.FIELD_UNDEFINED and reference fields to null.

reset

public abstract void reset()

Reset this XMLGregorianCalendar to its original values.

reset() is designed to allow the reuse of existing XMLGregorianCalendars thus saving resources associated with the creation of new XMLGregorianCalendars.

setYear

public abstract void setYear(BigInteger year)

Set low and high order component of XSD dateTime year field.

Unset this field by invoking the setter with a parameter value of null.

Parameters:: year - value constraints summarized in year field of date/time field mapping table.
Throws:: IllegalArgumentException - if year parameter is outside value constraints for the field as specified in date/time field mapping table.

setYear

public abstract void setYear(int year)

Set year of XSD dateTime year field.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Note: if the absolute value of the year parameter is less than 10^9, the eon component of the XSD year field is set to null by this method.

Parameters:: year - value constraints are summarized in year field of date/time field mapping table. If year is DatatypeConstants.FIELD_UNDEFINED, then eon is set to null.

setMonth

public abstract void setMonth(int month)

Set month.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: month - value constraints summarized in month field of date/time field mapping table.
Throws:: IllegalArgumentException - if month parameter is outside value constraints for the field as specified in date/time field mapping table.

setDay

public abstract void setDay(int day)

Set days in month.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: day - value constraints summarized in day field of date/time field mapping table.
Throws:: IllegalArgumentException - if day parameter is outside value constraints for the field as specified in date/time field mapping table.

setTimezone

public abstract void setTimezone(int offset)

Set the number of minutes in the timezone offset.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: offset - value constraints summarized in timezone field of date/time field mapping table.
Throws:: IllegalArgumentException - if offset parameter is outside value constraints for the field as specified in date/time field mapping table.

setTime

public void setTime(int hour, int minute, int second)

Set time as one unit.

Parameters:

hour - value constraints are summarized in hour field of date/time field mapping table.

minute - value constraints are summarized in minute field of date/time field mapping table.

second - value constraints are summarized in second field of date/time field mapping table.

Throws:

IllegalArgumentException - if any parameter is outside value constraints for the field as specified in date/time field mapping table.

See Also:

setHour

public abstract void setHour(int hour)

Set hours.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: hour - value constraints summarized in hour field of date/time field mapping table.
Throws:: IllegalArgumentException - if hour parameter is outside value constraints for the field as specified in date/time field mapping table.

setMinute

public abstract void setMinute(int minute)

Set minutes.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: minute - value constraints summarized in minute field of date/time field mapping table.
Throws:: IllegalArgumentException - if minute parameter is outside value constraints for the field as specified in date/time field mapping table.

setSecond

public abstract void setSecond(int second)

Set seconds.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: second - value constraints summarized in second field of date/time field mapping table.
Throws:: IllegalArgumentException - if second parameter is outside value constraints for the field as specified in date/time field mapping table.

setMillisecond

public abstract void setMillisecond(int millisecond)

Set milliseconds.

Unset this field by invoking the setter with a parameter value of DatatypeConstants.FIELD_UNDEFINED.

Parameters:: millisecond - value constraints summarized in second field of date/time field mapping table.
Throws:: IllegalArgumentException - if millisecond parameter is outside value constraints for the field as specified in date/time field mapping table.

setFractionalSecond

public abstract void setFractionalSecond(BigDecimal fractional)

Set fractional seconds.

Unset this field by invoking the setter with a parameter value of null.

Parameters:: fractional - value constraints summarized in second field of date/time field mapping table.
Throws:: IllegalArgumentException - if fractional parameter is outside value constraints for the field as specified in date/time field mapping table.

setTime

public void setTime(int hour, int minute, int second, BigDecimal fractional)

Set time as one unit, including the optional infinite precision fractional seconds.

Parameters:: hour - value constraints are summarized in hour field of date/time field mapping table.; minute - value constraints are summarized in minute field of date/time field mapping table.; second - value constraints are summarized in second field of date/time field mapping table.; fractional - value of null indicates this optional field is not set.
Throws:: IllegalArgumentException - if any parameter is outside value constraints for the field as specified in date/time field mapping table.

setTime

public void setTime(int hour, int minute, int second, int millisecond)

Set time as one unit, including optional milliseconds.

Parameters:: hour - value constraints are summarized in hour field of date/time field mapping table.; minute - value constraints are summarized in minute field of date/time field mapping table.; second - value constraints are summarized in second field of date/time field mapping table.; millisecond - value of DatatypeConstants.FIELD_UNDEFINED indicates this optional field is not set.
Throws:: IllegalArgumentException - if any parameter is outside value constraints for the field as specified in date/time field mapping table.

getEon

public abstract BigInteger getEon()

Returns the high order component for XML Schema 1.0 dateTime datatype field for year. null if this optional part of the year field is not defined.

Value constraints for this value are summarized in year field of date/time field mapping table.

Returns:

The eon of this XMLGregorianCalendar. The value returned is an integer multiple of 10^9.

See Also:

getYear

public abstract int getYear()

Returns the low order component for XML Schema 1.0 dateTime datatype field for year or DatatypeConstants.FIELD_UNDEFINED.

Value constraints for this value are summarized in year field of date/time field mapping table.

Returns:

The year of this XMLGregorianCalendar.

See Also:

getEonAndYear

public abstract BigInteger getEonAndYear()

Returns the XML Schema 1.0 dateTime datatype field for year.

Value constraints for this value are summarized in year field of date/time field mapping table.

Returns:

sum of eon and BigInteger.valueOf(year) when both fields are defined. When only year is defined, return it. When both eon and year are not defined, return null.

See Also:

getMonth

public abstract int getMonth()

Returns the month of this calendar or DatatypeConstants.FIELD_UNDEFINED.

Value constraints for this value are summarized in month field of date/time field mapping table.

Returns:: The month of this XMLGregorianCalendar, from 1 to 12.

getDay

public abstract int getDay()

Returns the day of month or DatatypeConstants.FIELD_UNDEFINED.

Value constraints for this value are summarized in day field of date/time field mapping table.

Returns:

The day of month of this XMLGregorianCalendar, from 1 to 31.

See Also:

getTimezone

public abstract int getTimezone()

Returns the Timezone offset in minutes or DatatypeConstants.FIELD_UNDEFINED if this optional field is not defined.

Value constraints for this value are summarized in timezone field of date/time field mapping table.

Returns:

The Timezone offset in minutes of this XMLGregorianCalendar.

See Also:

getHour

public abstract int getHour()

Returns the hour of day or DatatypeConstants.FIELD_UNDEFINED if this field is not defined.

Value constraints for this value are summarized in hour field of date/time field mapping table.

Returns:

The hour of day of this XMLGregorianCalendar, from 0 to 23.

See Also:

getMinute

public abstract int getMinute()

Returns the minute of hour or DatatypeConstants.FIELD_UNDEFINED if this field is not defined.

Value constraints for this value are summarized in minute field of date/time field mapping table.

Returns:

The minute of hour of this XMLGregorianCalendar, from 0 to 59.

See Also:

getSecond

public abstract int getSecond()

Returns the second of minute or DatatypeConstants.FIELD_UNDEFINED if this field is not defined. When this field is not defined, the optional xs:dateTime fractional seconds field, represented by getFractionalSecond() and getMillisecond(), must not be defined.

Value constraints for this value are summarized in second field of date/time field mapping table.

Returns:

The second of minute of this XMLGregorianCalendar, from 0 to 59.

See Also:

getMillisecond

public int getMillisecond()

Returns the millisecond precision of getFractionalSecond().

This method represents a convenience accessor to infinite precision fractional second value returned by getFractionalSecond(). The returned value is the rounded down to milliseconds value of getFractionalSecond(). When getFractionalSecond() returns null, this method must return DatatypeConstants.FIELD_UNDEFINED.

Value constraints for this value are summarized in second field of date/time field mapping table.

Returns:

The millisecond precision of this XMLGregorianCalendar.

See Also:

getFractionalSecond

public abstract BigDecimal getFractionalSecond()

Returns fractional seconds.

null is returned when this optional field is not defined.

Value constraints are detailed in second field of date/time field mapping table.

This optional field can only have a defined value when the xs:dateTime second field, represented by getSecond(), does not return DatatypeConstants.FIELD_UNDEFINED.

Returns:

Fractional seconds of this XMLGregorianCalendar.

See Also:

compare

public abstract int compare(XMLGregorianCalendar xmlGregorianCalendar)

Compare two instances of W3C XML Schema 1.0 date/time datatypes according to partial order relation defined in W3C XML Schema 1.0 Part 2, Section 3.2.7.3, Order relation on dateTime.

xsd:dateTime datatype field mapping to accessors of this class are defined in date/time field mapping table.

Parameters:: xmlGregorianCalendar - Instance of XMLGregorianCalendar to compare
Returns:: The relationship between this XMLGregorianCalendar and the specified xmlGregorianCalendar as DatatypeConstants.LESSER, DatatypeConstants.EQUAL, DatatypeConstants.GREATER or DatatypeConstants.INDETERMINATE.
Throws:: NullPointerException - if xmlGregorianCalendar is null.

normalize

public abstract XMLGregorianCalendar normalize()

Normalize this instance to UTC.

2000-03-04T23:00:00+03:00 normalizes to 2000-03-04T20:00:00Z

Implements W3C XML Schema Part 2, Section 3.2.7.3 (A).

Returns:: this XMLGregorianCalendar normalized to UTC.

equals

public boolean equals(Object obj)

Compares this calendar to the specified object. The result is true if and only if the argument is not null and is an XMLGregorianCalendar object that represents the same instant in time as this object.

Overrides:

equals in class Object

Parameters:

obj - to compare.

Returns:

true when obj is an instance of XMLGregorianCalendar and compare(XMLGregorianCalendar obj) returns DatatypeConstants.EQUAL, otherwise false.

See Also:

hashCode

public int hashCode()

Returns a hash code consistent with the definition of the equals method.

Overrides:

hashCode in class Object

Returns:

hash code of this object.

See Also:

toXMLFormat

public abstract String toXMLFormat()

Return the lexical representation of this instance. The format is specified in XML Schema 1.0 Part 2, Section 3.2.[7-14].1, Lexical Representation".

Specific target lexical representation format is determined by getXMLSchemaType().

Returns:: XML, as String, representation of this XMLGregorianCalendar
Throws:: IllegalStateException - if the combination of set fields does not match one of the eight defined XML Schema builtin date/time datatypes.

getXMLSchemaType

public abstract QName getXMLSchemaType()

Return the name of the XML Schema date/time type that this instance maps to. Type is computed based on fields that are set.

Required fields for XML Schema 1.0 Date/Time Datatypes.
*(timezone is optional for all date/time datatypes)*
Datatype	year	month	day	hour	minute	second
`DatatypeConstants.DATETIME`	X	X	X	X	X	X
`DatatypeConstants.DATE`	X	X	X
`DatatypeConstants.TIME`				X	X	X
`DatatypeConstants.GYEARMONTH`	X	X
`DatatypeConstants.GMONTHDAY`		X	X
`DatatypeConstants.GYEAR`	X
`DatatypeConstants.GMONTH`		X
`DatatypeConstants.GDAY`			X

Returns:: One of the following class constants: DatatypeConstants.DATETIME, DatatypeConstants.TIME, DatatypeConstants.DATE, DatatypeConstants.GYEARMONTH, DatatypeConstants.GMONTHDAY, DatatypeConstants.GYEAR, DatatypeConstants.GMONTH or DatatypeConstants.GDAY.
Throws:: IllegalStateException - if the combination of set fields does not match one of the eight defined XML Schema builtin date/time datatypes.

toString

public String toString()

Returns a String representation of this XMLGregorianCalendar Object.

The result is a lexical representation generated by toXMLFormat().

Overrides:

toString in class Object

Returns:

A non-null valid String representation of this XMLGregorianCalendar.

Throws:

IllegalStateException - if the combination of set fields does not match one of the eight defined XML Schema builtin date/time datatypes.

See Also:

isValid

public abstract boolean isValid()

Validate instance by getXMLSchemaType() constraints.

Returns:: true if data values are valid.

add

public abstract void add(Duration duration)

Add duration to this instance.

The computation is specified in XML Schema 1.0 Part 2, Appendix E, Adding durations to dateTimes. date/time field mapping table defines the mapping from XML Schema 1.0 dateTime fields to this class' representation of those fields.

Parameters:: duration - Duration to add to this XMLGregorianCalendar.
Throws:: NullPointerException - when duration parameter is null.

toGregorianCalendar

public abstract GregorianCalendar toGregorianCalendar()

Convert this XMLGregorianCalendar to a GregorianCalendar.

When this instance has an undefined field, this conversion relies on the java.util.GregorianCalendar default for its corresponding field. A notable difference between XML Schema 1.0 date/time datatypes and java.util.GregorianCalendar is that Timezone value is optional for date/time datatypes and it is a required field for java.util.GregorianCalendar. See javadoc for java.util.TimeZone.getDefault() on how the default is determined. To explicitly specify the TimeZone instance, see toGregorianCalendar(TimeZone, Locale, XMLGregorianCalendar).

Field by Field Conversion from this class to `java.util.GregorianCalendar`
`java.util.GregorianCalendar` field	`javax.xml.datatype.XMLGregorianCalendar` field
`ERA`	`getEonAndYear().signum() < 0 ? GregorianCalendar.BC : GregorianCalendar.AD`
`YEAR`	`getEonAndYear().abs().intValue()`*
`MONTH`	`getMonth()` - `DatatypeConstants.JANUARY` + `Calendar.JANUARY`
`DAY_OF_MONTH`	`getDay()`
`HOUR_OF_DAY`	`getHour()`
`MINUTE`	`getMinute()`
`SECOND`	`getSecond()`
`MILLISECOND`	get millisecond order from `getFractionalSecond()`*
`GregorianCalendar.setTimeZone(TimeZone)`	`getTimezone()` formatted into Custom timezone id

* designates possible loss of precision during the conversion due to source datatype having higher precision than target datatype.

To ensure consistency in conversion implementations, the new GregorianCalendar should be instantiated in following manner.

Using timeZone value as defined above, create a new java.util.GregorianCalendar(timeZone,Locale.getDefault()).
Initialize all GregorianCalendar fields by calling Calendar.clear().
Obtain a pure Gregorian Calendar by invoking GregorianCalendar.setGregorianChange( new Date(Long.MIN_VALUE)).
Its fields ERA, YEAR, MONTH, DAY_OF_MONTH, HOUR_OF_DAY, MINUTE, SECOND and MILLISECOND are set using the method Calendar.set(int,int)

Returns:

An instance of GregorianCalendar.

See Also:

toGregorianCalendar

public abstract GregorianCalendar toGregorianCalendar(TimeZone timezone, Locale aLocale, XMLGregorianCalendar defaults)

Convert this XMLGregorianCalendar along with provided parameters to a GregorianCalendar instance.

Since XML Schema 1.0 date/time datetypes has no concept of timezone ids or daylight savings timezone ids, this conversion operation allows the user to explicitly specify one with timezone parameter.

To compute the return value's TimeZone field,

when parameter timeZone is non-null, it is the timezone field.
else when this.getTimezone() != FIELD_UNDEFINED, create a java.util.TimeZone with a custom timezone id using the this.getTimezone().
else when defaults.getTimezone() != FIELD_UNDEFINED, create a java.util.TimeZone with a custom timezone id using defaults.getTimezone().
else use the GregorianCalendar default timezone value for the host is defined as specified by java.util.TimeZone.getDefault().

To ensure consistency in conversion implementations, the new GregorianCalendar should be instantiated in following manner.

Create a new java.util.GregorianCalendar(TimeZone, Locale) with TimeZone set as specified above and the Locale parameter.
Initialize all GregorianCalendar fields by calling Calendar.clear()
Obtain a pure Gregorian Calendar by invoking GregorianCalendar.setGregorianChange( new Date(Long.MIN_VALUE)).
Its fields ERA, YEAR, MONTH, DAY_OF_MONTH, HOUR_OF_DAY, MINUTE, SECOND and MILLISECOND are set using the method Calendar.set(int,int)

Parameters:: timezone - provide Timezone. null is a legal value.; aLocale - provide explicit Locale. Use default GregorianCalendar locale if value is null.; defaults - provide default field values to use when corresponding field for this instance is FIELD_UNDEFINED or null. If defaultsis null or a field within the specified defaults is undefined, just use java.util.GregorianCalendar defaults.
Returns:: a java.util.GregorianCalendar conversion of this instance.

getTimeZone

public abstract TimeZone getTimeZone(int defaultZoneoffset)

Returns a java.util.TimeZone for this class.

If timezone field is defined for this instance, returns TimeZone initialized with custom timezone id of zoneoffset. If timezone field is undefined, try the defaultZoneoffset that was passed in. If defaultZoneoffset is FIELD_UNDEFINED, return default timezone for this host. (Same default as java.util.GregorianCalendar).

Parameters:: defaultZoneoffset - default zoneoffset if this zoneoffset is DatatypeConstants.FIELD_UNDEFINED.
Returns:: TimeZone for this.

clone

public abstract Object clone()

Creates and returns a copy of this object.

Overrides:

clone in class Object

Returns:

copy of this Object

See Also:

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