java.lang.Object  
↳  javax.xml.datatype.Duration 
Immutable representation of a time span as defined in the W3C XML Schema 1.0 specification.
A Duration object represents a period of Gregorian time, which consists of six fields (years, months, days, hours, minutes, and seconds) plus a sign (+/) field.
The first five fields have nonnegative (>=0) integers or null (which represents that the field is not set), and the seconds field has a nonnegative decimal or null. A negative sign indicates a negative duration.
This class provides a number of methods that make it easy to use for the duration datatype of XML Schema 1.0 with the errata.
Duration objects only have partial order, where two values A and B maybe either:
For example, 30 days cannot be meaningfully compared to one month.
The compare(Duration)
method implements this
relationship.
See the isLongerThan(Duration)
method for details about
the order relationship among Duration
objects.
This class provides a set of basic arithmetic operations, such as addition, subtraction and multiplication. Because durations don't have total order, an operation could fail for some combinations of operations. For example, you cannot subtract 15 days from 1 month. See the javadoc of those methods for detailed conditions where this could happen.
Also, division of a duration by a number is not provided because
the Duration
class can only deal with finite precision
decimal numbers. For example, one cannot represent 1 sec divided by 3.
However, you could substitute a division by 3 with multiplying by numbers such as 0.3 or 0.333.
Because some operations of Duration
rely on Calendar
even though Duration
can hold very large or very small values,
some of the methods may not work correctly on such Duration
s.
The impacted methods document their dependency on Calendar
.
See also:
Public Constructors  

Public Methods  

Computes a new duration whose value is  
Adds this duration to a
Calendar object.
 
Adds this duration to a
Date object.
 
Partial order relation comparison with this  
Checks if this duration object has the same duration
as another  
Obtains the value of the DAYS field as an integer value,
or 0 if not present.
 
Gets the value of a field.
 
Obtains the value of the HOURS field as an integer value,
or 0 if not present.
 
Obtains the value of the MINUTES field as an integer value,
or 0 if not present.
 
Obtains the value of the MONTHS field as an integer value,
or 0 if not present.
 
Obtains the value of the SECONDS field as an integer value,
or 0 if not present.
 
Returns the sign of this duration in 1,0, or 1.
 
Returns the length of the duration in milliseconds.  
Returns the length of the duration in milliseconds.  
Return the name of the XML Schema date/time type that this instance maps to.  
Get the years value of this  
Returns a hash code consistent with the definition of the equals method.
 
Checks if this duration object is strictly longer than
another  
Checks if a field is set.
 
Checks if this duration object is strictly shorter than
another  
Computes a new duration whose value is  
Computes a new duration whose value is
factor times
longer than the value of this duration.
 
Returns a new
Duration object whose
value is this .
 
Converts the years and months fields into the days field by using a specific time instant as the reference point.  
Computes a new duration whose value is  
Returns a 
[Expand]
Inherited Methods  

From class
java.lang.Object

Computes a new duration whose value is this+rhs
.
For example,
"1 day" + "3 days" = "2 days" "1 year" + "1 day" = "1 year and 1 day" "(1 hour,50 minutes)" + "20 minutes" = "(1 hours,70 minutes)" "15 hours" + "3 days" = "(2 days,9 hours)" "1 year" + "1 day" = IllegalStateException
Since there's no way to meaningfully subtract 1 day from 1 month,
there are cases where the operation fails in
IllegalStateException
.
Formally, the computation is defined as follows.
Firstly, we can assume that two Duration
s to be added
are both positive without losing generality (i.e.,
(X)+Y=YX
, X+(Y)=XY
,
(X)+(Y)=(X+Y)
)
Addition of two positive Duration
s are simply defined as
field by field addition where missing fields are treated as 0.
A field of the resulting Duration
will be unset if and
only if respective fields of two input Duration
s are unset.
Note that lhs.add(rhs)
will be always successful if
lhs.signum()*rhs.signum()!=1
or both of them are
normalized.
Parameters  

rhs 
Duration to add to this Duration 
Returns  

Duration 
nonnull valid Duration object. 
Throws  

NullPointerException 
If the rhs parameter is null. 
IllegalStateException 
If two durations cannot be meaningfully added. For example, adding negative one day to one month causes this exception. 
See also:
Adds this duration to a Calendar
object.
Calls add(int, int)
in the
order of YEARS, MONTHS, DAYS, HOURS, MINUTES, SECONDS, and MILLISECONDS
if those fields are present. Because the Calendar
class
uses int to hold values, there are cases where this method
won't work correctly (for example if values of fields
exceed the range of int.)
Also, since this duration class is a Gregorian duration, this
method will not work correctly if the given Calendar
object is based on some other calendar systems.
Any fractional parts of this Duration
object
beyond milliseconds will be simply ignored. For example, if
this duration is "P1.23456S", then 1 is added to SECONDS,
234 is added to MILLISECONDS, and the rest will be unused.
Note that because add(int, int)
is using
int, Duration
with values beyond the
range of int in its fields
will cause overflow/underflow to the given Calendar
.
add(Duration)
provides the same
basic operation as this method while avoiding
the overflow/underflow issues.
Parameters  

calendar 
A calendar object whose value will be modified. 
Throws  

NullPointerException 
if the calendar parameter is null. 
Adds this duration to a Date
object.
The given date is first converted into
a GregorianCalendar
, then the duration
is added exactly like the addTo(Calendar)
method.
The updated time instant is then converted back into a
Date
object and used to update the given Date
object.
This somewhat redundant computation is necessary to unambiguously determine the duration of months and years.
Parameters  

date 
A date object whose value will be modified. 
Throws  

NullPointerException 
if the date parameter is null. 
Partial order relation comparison with this Duration
instance.
Comparison result must be in accordance with W3C XML Schema 1.0 Part 2, Section 3.2.7.6.2, Order relation on duration.
Return:
LESSER
if this Duration
is shorter than duration
parameterEQUAL
if this Duration
is equal to duration
parameterGREATER
if this Duration
is longer than duration
parameterINDETERMINATE
if a conclusive partial order relation cannot be determinedParameters  

duration 
to compare 
Returns  

int 
the relationship between this Duration and duration parameter as
LESSER , EQUAL , GREATER
or INDETERMINATE . 
Throws  

UnsupportedOperationException 
If the underlying implementation cannot reasonably process the request, e.g. W3C XML Schema allows for arbitrarily large/small/precise values, the request may be beyond the implementations capability. 
NullPointerException 
if duration is null . 
Checks if this duration object has the same duration
as another Duration
object.
For example, "P1D" (1 day) is equal to "PT24H" (24 hours).
Duration X is equal to Y if and only if time instant t+X and t+Y are the same for all the test time instants specified in the section 3.2.6.2 of the XML Schema 1.0 specification.
Note that there are cases where two Duration
s are
"incomparable" to each other, like one month and 30 days.
For example,
!new Duration("P1M").isShorterThan(new Duration("P30D")) !new Duration("P1M").isLongerThan(new Duration("P30D")) !new Duration("P1M").equals(new Duration("P30D"))
Parameters  

duration 
A nonnull valid Duration object. 
Returns  

boolean 
true if this duration is the same length as
duration .
false if duration is not a
Duration object, is null ,
or its length is different from this duration. 
Throws  

UnsupportedOperationException 
If the underlying implementation cannot reasonably process the request, e.g. W3C XML Schema allows for arbitrarily large/small/precise values, the request may be beyond the implementations capability. 
See also:
Obtains the value of the DAYS field as an integer value,
or 0 if not present.
This method works just like getYears()
except
that this method works on the DAYS field.
Returns  

int 
Days of this Duration .

Gets the value of a field.
Fields of a duration object may contain arbitrary large value.
Therefore this method is designed to return a Number
object.
In case of YEARS, MONTHS, DAYS, HOURS, and MINUTES, the returned
number will be a nonnegative integer. In case of seconds,
the returned number may be a nonnegative decimal value.
Parameters  

field 
one of the six Field constants (YEARS,MONTHS,DAYS,HOURS, MINUTES, or SECONDS.) 
Returns  

Number 
If the specified field is present, this method returns
a nonnull nonnegative Number object that
represents its value. If it is not present, return null.
For YEARS, MONTHS, DAYS, HOURS, and MINUTES, this method
returns a BigInteger object. For SECONDS, this
method returns a BigDecimal . 
Throws  

NullPointerException 
If the field is null .

Obtains the value of the HOURS field as an integer value,
or 0 if not present.
This method works just like getYears()
except
that this method works on the HOURS field.
Returns  

int 
Hours of this Duration .

Obtains the value of the MINUTES field as an integer value,
or 0 if not present.
This method works just like getYears()
except
that this method works on the MINUTES field.
Returns  

int 
Minutes of this Duration .

Obtains the value of the MONTHS field as an integer value,
or 0 if not present.
This method works just like getYears()
except
that this method works on the MONTHS field.
Returns  

int 
Months of this Duration .

Obtains the value of the SECONDS field as an integer value,
or 0 if not present.
This method works just like getYears()
except
that this method works on the SECONDS field.
Returns  

int 
seconds in the integer value. The fraction of seconds will be discarded (for example, if the actual value is 2.5, this method returns 2) 
Returns the sign of this duration in 1,0, or 1.
Returns  

int 
1 if this duration is negative, 0 if the duration is zero, and 1 if the duration is positive. 
Returns the length of the duration in milliseconds.
If the seconds field carries more digits than millisecond order,
those will be simply discarded (or in other words, rounded to zero.)
For example, for any Calendar value x
,
new Duration("PT10.00099S").getTimeInMills(x) == 10000
.new Duration("PT10.00099S").getTimeInMills(x) == 10000
.
Note that this method uses the addTo(Calendar)
method,
which may work incorrectly with Duration
objects with
very large values in its fields. See the addTo(Calendar)
method for details.
Parameters  

startInstant 
The length of a month/year varies. The startInstant is
used to disambiguate this variance. Specifically, this method
returns the difference between startInstant and
startInstant+duration 
Returns  

long 
milliseconds between startInstant and
startInstant plus this Duration 
Throws  

NullPointerException 
if startInstant parameter
is null.

Returns the length of the duration in milliseconds.
If the seconds field carries more digits than millisecond order,
those will be simply discarded (or in other words, rounded to zero.)
For example, for any Date
value x
,
new Duration("PT10.00099S").getTimeInMills(x) == 10000
.new Duration("PT10.00099S").getTimeInMills(x) == 10000
.
Note that this method uses the addTo(Date)
method,
which may work incorrectly with Duration
objects with
very large values in its fields. See the addTo(Date)
method for details.
Parameters  

startInstant 
The length of a month/year varies. The startInstant is
used to disambiguate this variance. Specifically, this method
returns the difference between startInstant and
startInstant+duration . 
Returns  

long 
milliseconds between startInstant and
startInstant plus this Duration 
Throws  

NullPointerException 
If the startInstant parameter is null. 
See also:
Return the name of the XML Schema date/time type that this instance
maps to. Type is computed based on fields that are set,
i.e. isSet(DatatypeConstants.Field)
== true
.
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 
DURATION 
X  X  X  X  X  X 
DURATION_DAYTIME 
X  X  X  X  
DURATION_YEARMONTH 
X  X 
Returns  

QName 
one of the following constants:
DURATION ,
DURATION_DAYTIME or
DURATION_YEARMONTH . 
Throws  

IllegalStateException 
If the combination of set fields does not match one of the XML Schema date/time datatypes. 
Get the years value of this Duration
as an int
or 0
if not present.
getYears()
is a convenience method for
getField(DatatypeConstants.YEARS)
.
As the return value is an int
, an incorrect value will be returned for Duration
s
with years that go beyond the range of an int
.
Use getField(DatatypeConstants.YEARS)
to avoid possible loss of precision.
Returns  

int 
If the years field is present, return its value as an int , else return 0 .

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

int 
this object's hash code. 
See also:
Checks if this duration object is strictly longer than
another Duration
object.
Duration X is "longer" than Y if and only if X>Y as defined in the section 3.2.6.2 of the XML Schema 1.0 specification.
For example, "P1D" (one day) > "PT12H" (12 hours) and "P2Y" (two years) > "P23M" (23 months).
Parameters  

duration 
Duration to test this Duration against. 
Returns  

boolean 
true if the duration represented by this object is longer than the given duration. false otherwise. 
Throws  

UnsupportedOperationException 
If the underlying implementation cannot reasonably process the request, e.g. W3C XML Schema allows for arbitrarily large/small/precise values, the request may be beyond the implementations capability. 
NullPointerException 
If duration is null. 
See also:
Checks if a field is set. A field of a duration object may or may not be present. This method can be used to test if a field is present.
Parameters  

field 
one of the six Field constants (YEARS,MONTHS,DAYS,HOURS, MINUTES, or SECONDS.) 
Returns  

boolean 
true if the field is present. false if not. 
Throws  

NullPointerException 
If the field parameter is null. 
Checks if this duration object is strictly shorter than
another Duration
object.
Parameters  

duration 
Duration to test this Duration against. 
Returns  

boolean 
true if duration parameter is shorter than this Duration ,
else false . 
Throws  

UnsupportedOperationException 
If the underlying implementation cannot reasonably process the request, e.g. W3C XML Schema allows for arbitrarily large/small/precise values, the request may be beyond the implementations capability. 
NullPointerException 
if duration is null. 
See also:
Computes a new duration whose value is factor
times
longer than the value of this duration.
This method is provided for the convenience. It is functionally equivalent to the following code:
multiply(new BigDecimal(String.valueOf(factor)))
Parameters  

factor 
Factor times longer of new Duration to create. 
Returns  

Duration 
New Duration that is factor times longer than this Duration . 
See also:
Computes a new duration whose value is factor
times
longer than the value of this duration.
For example,
"P1M" (1 month) * "12" = "P12M" (12 months) "PT1M" (1 min) * "0.3" = "PT18S" (18 seconds) "P1M" (1 month) * "1.5" = IllegalStateException
Since the Duration
class is immutable, this method
doesn't change the value of this object. It simply computes
a new Duration object and returns it.
The operation will be performed field by field with the precision
of BigDecimal
. Since all the fields except seconds are
restricted to hold integers,
any fraction produced by the computation will be
carried down toward the next lower unit. For example,
if you multiply "P1D" (1 day) with "0.5", then it will be 0.5 day,
which will be carried down to "PT12H" (12 hours).
When fractions of month cannot be meaningfully carried down
to days, or year to months, this will cause an
IllegalStateException
to be thrown.
For example if you multiple one month by 0.5.
To avoid IllegalStateException
, use
the normalizeWith(Calendar)
method to remove the years
and months fields.
Parameters  

factor 
to multiply by 
Returns  

Duration 
returns a nonnull valid Duration object 
Throws  

IllegalStateException 
if operation produces fraction in the months field. 
NullPointerException 
if the factor parameter is
null .

Returns a new Duration
object whose
value is this
.
Since the Duration
class is immutable, this method
doesn't change the value of this object. It simply computes
a new Duration object and returns it.
Returns  

Duration 
always return a nonnull valid Duration object.

Converts the years and months fields into the days field by using a specific time instant as the reference point.
For example, duration of one month normalizes to 31 days given the start time instance "July 8th 2003, 17:40:32".
Formally, the computation is done as follows:
Calendar
object
by using the add(int, int)
methodNote that since the Calendar class uses int
to
hold the value of year and month, this method may produce
an unexpected result if this duration object holds
a very large value in the years or months fields.
Parameters  

startTimeInstant 
Calendar reference point. 
Returns  

Duration 
Duration of years and months of this Duration as days. 
Throws  

NullPointerException 
If the startTimeInstant parameter is null. 
Computes a new duration whose value is thisrhs
.
For example:
"1 day"  "3 days" = "4 days" "1 year"  "1 day" = IllegalStateException "(1 hour,50 minutes)"  "20 minutes" = "(1hours,30 minutes)" "15 hours"  "3 days" = "3 days and 15 hours" "1 year"  "1 day" = "1 year and 1 day"
Since there's no way to meaningfully subtract 1 day from 1 month,
there are cases where the operation fails in IllegalStateException
.
Formally the computation is defined as follows.
First, we can assume that two Duration
s are both positive
without losing generality. (i.e.,
(X)Y=(X+Y)
, X(Y)=X+Y
,
(X)(Y)=(XY)
)
Then two durations are subtracted field by field. If the sign of any nonzero field F is different from the sign of the most significant field, 1 (if F is negative) or 1 (otherwise) will be borrowed from the next bigger unit of F.
This process is repeated until all the nonzero fields have the same sign.
If a borrow occurs in the days field (in other words, if
the computation needs to borrow 1 or 1 month to compensate
days), then the computation fails by throwing an
IllegalStateException
.
Parameters  

rhs 
Duration to subtract from this Duration . 
Returns  

Duration 
New Duration created from subtracting rhs from this Duration . 
Throws  

IllegalStateException 
If two durations cannot be meaningfully subtracted. For example, subtracting one day from one month causes this exception. 
NullPointerException 
If the rhs parameter is null. 
See also:
Returns a String
representation of this Duration
Object
.
The result is formatted according to the XML Schema 1.0 specification and can be always parsed back later into the
equivalent Duration
Object
by newDuration(String)
.
Formally, the following holds for any Duration
Object
x:
new Duration(x.toString()).equals(x)
Returns  

String 
A nonnull valid String representation of this Duration .
