net.sf.saxon.value
Class DoubleValue

java.lang.Object
  extended by net.sf.saxon.value.Value<AtomicValue>
      extended by net.sf.saxon.value.AtomicValue
          extended by net.sf.saxon.value.NumericValue
              extended by net.sf.saxon.value.DoubleValue
All Implemented Interfaces:
Comparable, PullEvent, GroundedValue<AtomicValue>, Item<AtomicValue>, ValueRepresentation<AtomicValue>, ConversionResult

public final class DoubleValue
extends NumericValue

A numeric (double precision floating point) value


Field Summary
static DoubleValue NaN
           
static DoubleValue NEGATIVE_ZERO
           
static DoubleValue ONE
           
static DoubleValue ZERO
           
 
Fields inherited from class net.sf.saxon.value.AtomicValue
typeLabel
 
Fields inherited from class net.sf.saxon.value.Value
INDETERMINATE_ORDERING
 
Fields inherited from interface net.sf.saxon.om.ValueRepresentation
EMPTY_VALUE_ARRAY
 
Constructor Summary
DoubleValue(double value)
          Constructor supplying a double
DoubleValue(double value, AtomicType type)
          Constructor supplying a double and an AtomicType, for creating a value that belongs to a user-defined subtype of xs:double.
 
Method Summary
 NumericValue abs()
          Get the absolute value as defined by the XPath abs() function
 NumericValue ceiling()
          Implement the XPath ceiling() function
 int compareTo(long other)
          Compare the value to a long.
 AtomicValue copyAsSubType(AtomicType typeLabel)
          Create a copy of this atomic value, with a different type label
static CharSequence doubleToString(double value)
          Internal method used for conversion of a double to a string
 boolean effectiveBooleanValue()
          Get the effective boolean value
 NumericValue floor()
          Implement the XPath floor() function
static DoubleValue fromInternalForm(String hex)
           
 CharSequence getCanonicalLexicalRepresentation()
          Get the canonical lexical representation as defined in XML Schema.
 BigDecimal getDecimalValue()
          Get the numeric value converted to a decimal
 double getDoubleValue()
          Return this numeric value as a double
 float getFloatValue()
          Get the numeric value converted to a float
 CharSequence getPrimitiveStringValue()
          Convert the double to a string according to the XPath 2.0 rules
 BuiltInAtomicType getPrimitiveType()
          Determine the primitive type of the value.
 Comparable getSchemaComparable()
          Get an object that implements XML Schema comparison semantics
 int hashCode()
          Get the hashCode.
 boolean isIdentical(Value v)
          Determine whether two atomic values are identical, as determined by XML Schema rules.
 boolean isNaN()
          Test whether the value is the double/float value NaN
 boolean isWholeNumber()
          Determine whether the value is a whole number, that is, whether it compares equal to some integer
 long longValue()
          Return the numeric value as a Java long.
static void main(String[] args)
           
static DoubleValue makeDoubleValue(double value)
          Static factory method (for convenience in compiled bytecode)
 NumericValue negate()
          Negate the value
static void printInternalForm(double d)
          Diagnostic method: print the sign, exponent, and significand
 NumericValue round(int scale)
          Implement the XPath round() function
 NumericValue roundHalfToEven(int scale)
          Implement the XPath round-to-half-even() function
 int signum()
          Determine whether the value is negative, zero, or positive
 
Methods inherited from class net.sf.saxon.value.NumericValue
compareTo, equals, getXPathComparable, isInteger, parseNumber, toString
 
Methods inherited from class net.sf.saxon.value.AtomicValue
asAtomic, checkPermittedContents, getCardinality, getComponent, getItemType, getLength, getStringValue, getStringValueCS, getTypedValue, getTypeLabel, itemAt, iterate, process, setTypeLabel, subsequence
 
Methods inherited from class net.sf.saxon.value.Value
asItem, asItem, asIterator, asValue, convertToJava, fromItem, getIterator, getSequenceLength, reduce
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

ZERO

public static final DoubleValue ZERO

NEGATIVE_ZERO

public static final DoubleValue NEGATIVE_ZERO

ONE

public static final DoubleValue ONE

NaN

public static final DoubleValue NaN
Constructor Detail

DoubleValue

public DoubleValue(double value)
Constructor supplying a double

Parameters:
value - the value of the NumericValue

DoubleValue

public DoubleValue(double value,
                   AtomicType type)
Constructor supplying a double and an AtomicType, for creating a value that belongs to a user-defined subtype of xs:double. It is the caller's responsibility to ensure that the supplied value conforms to the supplied type.

Parameters:
value - the value of the NumericValue
type - the type of the value. This must be a subtype of xs:double, and the value must conform to this type. The methosd does not check these conditions.
Method Detail

makeDoubleValue

public static DoubleValue makeDoubleValue(double value)
Static factory method (for convenience in compiled bytecode)

Parameters:
value - the value of the double
Returns:
a new DoubleValue

copyAsSubType

public AtomicValue copyAsSubType(AtomicType typeLabel)
Create a copy of this atomic value, with a different type label

Specified by:
copyAsSubType in class AtomicValue
Parameters:
typeLabel - the type label of the new copy. The caller is responsible for checking that the value actually conforms to this type.
Returns:
the copied value

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

getDoubleValue

public double getDoubleValue()
Return this numeric value as a double

Specified by:
getDoubleValue in class NumericValue
Returns:
the value as a double

getFloatValue

public float getFloatValue()
Get the numeric value converted to a float

Specified by:
getFloatValue in class NumericValue
Returns:
a float representing this numeric value; NaN if it cannot be converted

getDecimalValue

public BigDecimal getDecimalValue()
                           throws XPathException
Get the numeric value converted to a decimal

Specified by:
getDecimalValue in class NumericValue
Returns:
a decimal representing this numeric value;
Throws:
XPathException - if the value cannot be converted, for example if it is NaN or infinite

longValue

public long longValue()
               throws XPathException
Return the numeric value as a Java long.

Specified by:
longValue in class NumericValue
Returns:
the numeric value as a Java long. This performs truncation towards zero.
Throws:
XPathException - if the value cannot be converted

hashCode

public int hashCode()
Get the hashCode. This must conform to the rules for other NumericValue hashcodes

Specified by:
hashCode in class NumericValue
Returns:
the hash code of the numeric value
See Also:
NumericValue.hashCode()

isNaN

public boolean isNaN()
Test whether the value is the double/float value NaN

Overrides:
isNaN in class AtomicValue
Returns:
true if the value is float NaN or double NaN or precisionDecimal NaN; otherwise false

effectiveBooleanValue

public boolean effectiveBooleanValue()
Get the effective boolean value

Overrides:
effectiveBooleanValue in class AtomicValue
Returns:
the effective boolean value (true unless the value is zero or NaN)

getPrimitiveStringValue

public CharSequence getPrimitiveStringValue()
Convert the double to a string according to the XPath 2.0 rules

Specified by:
getPrimitiveStringValue in class AtomicValue
Returns:
the string value

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 xs:double, the canonical representation always uses exponential notation.

Overrides:
getCanonicalLexicalRepresentation in class Value<AtomicValue>
Returns:
the canonical lexical representation if defined in XML Schema; otherwise, the result of casting to string according to the XPath 2.0 rules

doubleToString

public static CharSequence doubleToString(double value)
Internal method used for conversion of a double to a string

Parameters:
value - the actual value
Returns:
the value converted to a string, according to the XPath casting rules.

negate

public NumericValue negate()
Negate the value

Specified by:
negate in class NumericValue
Returns:
a value, of the same type as the original, with its sign inverted

floor

public NumericValue floor()
Implement the XPath floor() function

Specified by:
floor in class NumericValue
Returns:
a value, of the same type as that supplied, rounded towards minus infinity

ceiling

public NumericValue ceiling()
Implement the XPath ceiling() function

Specified by:
ceiling in class NumericValue
Returns:
a value, of the same type as that supplied, rounded towards plus infinity

round

public NumericValue round(int scale)
Implement the XPath round() function

Specified by:
round in class NumericValue
Returns:
a value, of the same type as that supplied, rounded towards the nearest whole number (0.5 rounded up)

roundHalfToEven

public NumericValue roundHalfToEven(int scale)
Implement the XPath round-to-half-even() function

Specified by:
roundHalfToEven in class NumericValue
Parameters:
scale - the decimal position for rounding: e.g. 2 rounds to a multiple of 0.01, while -2 rounds to a multiple of 100
Returns:
a value, of the same type as the original, rounded towards the nearest multiple of 10**(-scale), with rounding towards the nearest even number if two values are equally near

signum

public int signum()
Determine whether the value is negative, zero, or positive

Specified by:
signum in class NumericValue
Returns:
-1 if negative, 0 if zero (including negative zero) or NaN, +1 if positive

isWholeNumber

public boolean isWholeNumber()
Determine whether the value is a whole number, that is, whether it compares equal to some integer

Specified by:
isWholeNumber in class NumericValue
Returns:
true if the value is a whole number

abs

public NumericValue abs()
Get the absolute value as defined by the XPath abs() function

Specified by:
abs in class NumericValue
Returns:
the absolute value
Since:
9.2

compareTo

public int compareTo(long other)
Compare the value to a long.

Specified by:
compareTo in class NumericValue
Parameters:
other - the value to be compared with
Returns:
-1 if this is less, 0 if this is equal, +1 if this is greater or if this is NaN

getSchemaComparable

public Comparable getSchemaComparable()
Get an object that implements XML Schema comparison semantics

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

isIdentical

public boolean isIdentical(Value v)
Determine whether two atomic values are identical, as determined by XML Schema rules. This is a stronger test than equality (even schema-equality); for example two dateTime values are not identical unless they are in the same timezone.

Note that even this check ignores the type annotation of the value. The integer 3 and the short 3 are considered identical, even though they are not fully interchangeable. "Identical" means the same point in the value space, regardless of type annotation.

NaN is identical to itself.

Overrides:
isIdentical in class AtomicValue
Parameters:
v - the other value to be compared with this one
Returns:
true if the two values are identical, false otherwise.

printInternalForm

public static void printInternalForm(double d)
Diagnostic method: print the sign, exponent, and significand

Parameters:
d - the double to be diagnosed

fromInternalForm

public static DoubleValue fromInternalForm(String hex)

main

public static void main(String[] args)


Copyright (c) 2004-2011 Saxonica Limited. All rights reserved.