net.sf.saxon.value
Class DateTimeValue

java.lang.Object
  extended by net.sf.saxon.value.Value
      extended by net.sf.saxon.value.AtomicValue
          extended by net.sf.saxon.value.CalendarValue
              extended by net.sf.saxon.value.DateTimeValue
All Implemented Interfaces:
Serializable, Comparable, PullEvent, SequenceIterable, GroundedValue, Item, ValueRepresentation, ConversionResult

public final class DateTimeValue
extends CalendarValue
implements Comparable

A value of type DateTime

See Also:
Serialized Form

Field Summary
static DateTimeValue javaOrigin
          Fixed date/time used by Java (and Unix) as the origin of the universe: 1970-01-01
 
Fields inherited from class net.sf.saxon.value.CalendarValue
NO_TIMEZONE
 
Fields inherited from class net.sf.saxon.value.Value
EMPTY_CLASS_ARRAY, INDETERMINATE_ORDERING
 
Fields inherited from interface net.sf.saxon.om.ValueRepresentation
EMPTY_VALUE_ARRAY
 
Fields inherited from interface net.sf.saxon.om.ValueRepresentation
EMPTY_VALUE_ARRAY
 
Constructor Summary
DateTimeValue(Calendar calendar, boolean tzSpecified)
          Constructor: create a dateTime value given a Java calendar object
DateTimeValue(int year, byte month, byte day, byte hour, byte minute, byte second, int microsecond, int tz)
          Constructor: construct a DateTimeValue from its components.
 
Method Summary
 CalendarValue add(DurationValue duration)
          Add a duration to a dateTime
 CalendarValue adjustTimezone(int timezone)
          Return a new dateTime with the same normalized value, but in a different timezone.
 int compareTo(CalendarValue other, XPathContext context)
          Compare the value to another dateTime value, following the XPath comparison semantics
 int compareTo(Object v2)
          Context-free comparison of two DateTimeValue values.
 ConversionResult convertPrimitive(BuiltInAtomicType requiredType, boolean validate, XPathContext context)
          Convert to target data type
 Object convertToJava(Class target, XPathContext context)
          Convert to Java object (for passing to external functions)
 AtomicValue copyAsSubType(AtomicType typeLabel)
          Make a copy of this date, time, or dateTime value, but with a new type label
 boolean equals(Object o)
          Context-free comparison of two dateTime values
static DateTimeValue fromJavaDate(Date suppliedDate)
          Factory method: create a dateTime value given a Java Date object.
static DateTimeValue fromJulianInstant(BigDecimal instant)
          Get the DateTimeValue corresponding to a given Julian instant
 GregorianCalendar getCalendar()
          Get a Java Calendar object representing the value of this DateTime.
 CharSequence getCanonicalLexicalRepresentation()
          Get the canonical lexical representation as defined in XML Schema.
 ComparisonKey getComparisonKey(XPathContext context)
          Get a comparison key for this value.
 AtomicValue getComponent(int component)
          Get a component of the value.
static DateTimeValue getCurrentDateTime(XPathContext context)
          Get the dateTime value representing the nominal date/time of this transformation run.
 byte getDay()
          Get the day component, 1-31
 byte getHour()
          Get the hour component, 0-23
 int getMicrosecond()
          Get the microsecond component, 0-999999
 byte getMinute()
          Get the minute component, 0-59
 byte getMonth()
          Get the month component, 1-12
 BuiltInAtomicType getPrimitiveType()
          Determine the primitive type of the value.
 Comparable getSchemaComparable()
          Get a Comparable value that implements the XML Schema ordering comparison semantics for this value.
 byte getSecond()
          Get the second component, 0-59
 CharSequence getStringValueCS()
          Convert to string
 int getYear()
          Get the year component, in its internal form (which allows a year zero)
 int hashCode()
          Hash code for context-free comparison of date time values.
static ConversionResult makeDateTimeValue(CharSequence s)
          Factory method: create a dateTime value from a supplied string, in ISO 8601 format
static DateTimeValue makeDateTimeValue(DateValue date, TimeValue time)
          Factory method: create a dateTime value given a date and a time.
 DateTimeValue normalize(XPathContext cc)
          Normalize the date and time to be in timezone Z.
 DayTimeDurationValue subtract(CalendarValue other, XPathContext context)
          Determine the difference between two points in time, as a duration
 DateTimeValue toDateTime()
          Convert the value to a DateTime, retaining all the components that are actually present, and substituting conventional values for components that are missing.
 BigDecimal toJulianInstant()
          Get the Julian instant: a decimal value whose integer part is the Julian day number multiplied by the number of seconds per day, and whose fractional part is the fraction of the second.
 
Methods inherited from class net.sf.saxon.value.CalendarValue
adjustTimezone, appendTimezone, appendTimezone, getStringValue, getTimezoneInMinutes, getXPathComparable, hasTimezone, removeTimezone, setTimezoneInMinutes
 
Methods inherited from class net.sf.saxon.value.AtomicValue
asAtomic, checkPermittedContents, convert, convert, effectiveBooleanValue, getCardinality, getItemType, getLength, getTypedValue, getTypeLabel, isNaN, itemAt, iterate, process, setTypeLabel, subsequence, toString
 
Methods inherited from class net.sf.saxon.value.Value
asItem, asItem, asIterator, asValue, convertJavaObjectToXPath, convertToJava, fromItem, getIterator, iterate, makeQNameValue, reduce, stringToNumber
 
Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

javaOrigin

public static final DateTimeValue javaOrigin
Fixed date/time used by Java (and Unix) as the origin of the universe: 1970-01-01

Constructor Detail

DateTimeValue

public DateTimeValue(Calendar calendar,
                     boolean tzSpecified)
Constructor: create a dateTime value given a Java calendar object

Parameters:
calendar - holds the date and time
tzSpecified - indicates whether the timezone is specified

DateTimeValue

public DateTimeValue(int year,
                     byte month,
                     byte day,
                     byte hour,
                     byte minute,
                     byte second,
                     int microsecond,
                     int tz)
Constructor: construct a DateTimeValue from its components. This constructor performs no validation.

Parameters:
year - The year as held internally (note that the year before 1AD is 0)
month - The month, 1-12
day - The day 1-31
hour - the hour value, 0-23
minute - the minutes value, 0-59
second - the seconds value, 0-59
microsecond - the number of microseconds, 0-999999
tz - the timezone displacement in minutes from UTC. Supply the value CalendarValue.NO_TIMEZONE if there is no timezone component.
Method Detail

getCurrentDateTime

public static DateTimeValue getCurrentDateTime(XPathContext context)
Get the dateTime value representing the nominal date/time of this transformation run. Two calls within the same query or transformation will always return the same answer.

Parameters:
context - the XPath dynamic context. May be null, in which case the current date and time are taken directly from the system clock
Returns:
the current xs:dateTime

fromJavaDate

public static DateTimeValue fromJavaDate(Date suppliedDate)
                                  throws XPathException
Factory method: create a dateTime value given a Java Date object. The returned dateTime value will always have a timezone, which will always be UTC.

Parameters:
suppliedDate - holds the date and time
Returns:
the corresponding xs:dateTime value
Throws:
XPathException

makeDateTimeValue

public static DateTimeValue makeDateTimeValue(DateValue date,
                                              TimeValue time)
                                       throws XPathException
Factory method: create a dateTime value given a date and a time.

Parameters:
date - the date
time - the time
Returns:
the dateTime with the given components. If either component is null, returns null
Throws:
XPathException - if the timezones are both present and inconsistent

makeDateTimeValue

public static ConversionResult makeDateTimeValue(CharSequence s)
Factory method: create a dateTime value from a supplied string, in ISO 8601 format

Parameters:
s - a string in the lexical space of xs:dateTime
Returns:
either a DateTimeValue representing the xs:dateTime supplied, or a ValidationFailure if the lexical value was invalid

getPrimitiveType

public BuiltInAtomicType getPrimitiveType()
Determine the primitive type of the value. This delivers the same answer as getItemType().getPrimitiveItemType(). The primitive types are the 19 primitive types of XML Schema, plus xs:integer, xs:dayTimeDuration and xs:yearMonthDuration, and xs:untypedAtomic. For external objects, the result is AnyAtomicType.

Specified by:
getPrimitiveType in class AtomicValue
Returns:
the primitive type

getYear

public int getYear()
Get the year component, in its internal form (which allows a year zero)

Returns:
the year component

getMonth

public byte getMonth()
Get the month component, 1-12

Returns:
the month component

getDay

public byte getDay()
Get the day component, 1-31

Returns:
the day component

getHour

public byte getHour()
Get the hour component, 0-23

Returns:
the hour component (never 24, even if the input was specified as 24:00:00)

getMinute

public byte getMinute()
Get the minute component, 0-59

Returns:
the minute component

getSecond

public byte getSecond()
Get the second component, 0-59

Returns:
the second component

getMicrosecond

public int getMicrosecond()
Get the microsecond component, 0-999999

Returns:
the microsecond component

toDateTime

public DateTimeValue toDateTime()
Convert the value to a DateTime, retaining all the components that are actually present, and substituting conventional values for components that are missing. (This method does nothing in the case of xs:dateTime, but is there to implement a method in the CalendarValue interface).

Specified by:
toDateTime in class CalendarValue
Returns:
the value as an xs:dateTime

normalize

public DateTimeValue normalize(XPathContext cc)
                        throws NoDynamicContextException
Normalize the date and time to be in timezone Z.

Parameters:
cc - used to supply the implicit timezone, used when the value has no explicit timezone
Returns:
in general, a new DateTimeValue in timezone Z, representing the same instant in time. Returns the original DateTimeValue if this is already in timezone Z.
Throws:
NoDynamicContextException - if the implicit timezone is needed and is not available

getComparisonKey

public ComparisonKey getComparisonKey(XPathContext context)
                               throws NoDynamicContextException
Get a comparison key for this value. Two values are equal if and only if they their comparison keys are equal

Specified by:
getComparisonKey in class CalendarValue
Parameters:
context - XPath dynamic context
Returns:
a comparison key
Throws:
NoDynamicContextException - if the implicit timezone is needed and is not available

toJulianInstant

public BigDecimal toJulianInstant()
Get the Julian instant: a decimal value whose integer part is the Julian day number multiplied by the number of seconds per day, and whose fractional part is the fraction of the second. This method operates on the local time, ignoring the timezone. The caller should call normalize() before calling this method to get a normalized time.

Returns:
the Julian instant corresponding to this xs:dateTime value

fromJulianInstant

public static DateTimeValue fromJulianInstant(BigDecimal instant)
Get the DateTimeValue corresponding to a given Julian instant

Parameters:
instant - the Julian instant: a decimal value whose integer part is the Julian day number multiplied by the number of seconds per day, and whose fractional part is the fraction of the second.
Returns:
the xs:dateTime value corresponding to the Julian instant. This will always be in timezone Z.

getCalendar

public GregorianCalendar getCalendar()
Get a Java Calendar object representing the value of this DateTime. This will respect the timezone if there is one, or be in GMT otherwise.

Specified by:
getCalendar in class CalendarValue
Returns:
a Java GregorianCalendar object representing the value of this xs:dateTime value.

convertPrimitive

public ConversionResult convertPrimitive(BuiltInAtomicType requiredType,
                                         boolean validate,
                                         XPathContext context)
Convert to target data type

Parameters:
requiredType - an integer identifying the required atomic type
context - the XPath dynamic context
validate - true if validation is required. If set to false, the caller guarantees that the value is valid for the target data type, and that further validation is therefore not required. Note that a validation failure may be reported even if validation was not requested.
Returns:
an AtomicValue, a value of the required type; or an ErrorValue

getStringValueCS

public CharSequence getStringValueCS()
Convert to string

Specified by:
getStringValueCS in interface Item
Specified by:
getStringValueCS in interface ValueRepresentation
Overrides:
getStringValueCS in class AtomicValue
Returns:
ISO 8601 representation. The value returned is the localized representation, that is it uses the timezone contained within the value itself.
See Also:
Item.getStringValue()

getCanonicalLexicalRepresentation

public CharSequence getCanonicalLexicalRepresentation()
Get the canonical lexical representation as defined in XML Schema. This is not always the same as the result of casting to a string according to the XPath rules. For an xs:dateTime it is the date/time adjusted to UTC.

Overrides:
getCanonicalLexicalRepresentation in class Value
Returns:
the canonical lexical representation as defined in XML Schema

copyAsSubType

public AtomicValue copyAsSubType(AtomicType typeLabel)
Make a copy of this date, time, or dateTime value, but with a new type label

Specified by:
copyAsSubType in class AtomicValue
Parameters:
typeLabel - the type label to be attached to the new copy. It is the caller's responsibility to ensure that the value actually conforms to the rules for this type.
Returns:
the copied value

adjustTimezone

public CalendarValue adjustTimezone(int timezone)
Return a new dateTime with the same normalized value, but in a different timezone.

Specified by:
adjustTimezone in class CalendarValue
Parameters:
timezone - the new timezone offset, in minutes
Returns:
the date/time in the new timezone. This will be a new DateTimeValue unless no change was required to the original value

add

public CalendarValue add(DurationValue duration)
                  throws XPathException
Add a duration to a dateTime

Specified by:
add in class CalendarValue
Parameters:
duration - the duration to be added (may be negative)
Returns:
the new date
Throws:
XPathException - if the duration is an xs:duration, as distinct from a subclass thereof

subtract

public DayTimeDurationValue subtract(CalendarValue other,
                                     XPathContext context)
                              throws XPathException
Determine the difference between two points in time, as a duration

Overrides:
subtract in class CalendarValue
Parameters:
other - the other point in time
context - the XPath dynamic context
Returns:
the duration as an xs:dayTimeDuration
Throws:
XPathException - for example if one value is a date and the other is a time

convertToJava

public Object convertToJava(Class target,
                            XPathContext context)
                     throws XPathException
Convert to Java object (for passing to external functions)

Overrides:
convertToJava in class Value
Parameters:
target - the required target class
context - the XPath dynamic evaluation context
Returns:
the (boxed) Java object that best represents the XPath value
Throws:
XPathException

getComponent

public AtomicValue getComponent(int component)
                         throws XPathException
Get a component of the value. Returns null if the timezone component is requested and is not present.

Overrides:
getComponent in class AtomicValue
Parameters:
component - identifies the required component, as a constant defined in class Component, for example Component.HOURS
Returns:
the value of the requested component of this value
Throws:
XPathException

compareTo

public int compareTo(CalendarValue other,
                     XPathContext context)
              throws NoDynamicContextException
Compare the value to another dateTime value, following the XPath comparison semantics

Specified by:
compareTo in class CalendarValue
Parameters:
other - The other dateTime value
context - XPath dynamic evaluation context
Returns:
negative value if this one is the earler, 0 if they are chronologically equal, positive value if this one is the later. For this purpose, dateTime values with an unknown timezone are considered to be values in the implicit timezone (the Comparable interface requires a total ordering).
Throws:
ClassCastException - if the other value is not a DateTimeValue (the parameter is declared as CalendarValue to satisfy the interface)
NoDynamicContextException - if the implicit timezone is needed and is not available

compareTo

public int compareTo(Object v2)
Context-free comparison of two DateTimeValue values. For this to work, the two values must either both have a timezone or both have none.

Specified by:
compareTo in interface Comparable
Parameters:
v2 - the other value
Returns:
the result of the comparison: -1 if the first is earlier, 0 if they are equal, +1 if the first is later
Throws:
ClassCastException - if the values are not comparable (which might be because no timezone is available)

getSchemaComparable

public Comparable getSchemaComparable()
Description copied from class: AtomicValue
Get a Comparable value that implements the XML Schema ordering comparison semantics for this value. An implementation must be provided for all atomic types.

In the case of data types that are partially ordered, the returned Comparable extends the standard semantics of the compareTo() method by returning the value Value.INDETERMINATE_ORDERING when there is no defined order relationship between two given values. This value is also returned when two values of different types are compared.

Specified by:
getSchemaComparable in class AtomicValue
Returns:
a Comparable that follows XML Schema comparison rules

equals

public boolean equals(Object o)
Context-free comparison of two dateTime values

Specified by:
equals in class AtomicValue
Parameters:
o - the other date time value
Returns:
true if the two values represent the same instant in time
Throws:
ClassCastException - if one of the values has a timezone and the other does not

hashCode

public int hashCode()
Hash code for context-free comparison of date time values. Note that equality testing and therefore hashCode() works only for values with a timezone

Overrides:
hashCode in class Object
Returns:
a hash code


Copyright (C) Michael H. Kay. All rights reserved.