Package net.sf.saxon.value

Class NumericValue

java.lang.Object
net.sf.saxon.value.Value
net.sf.saxon.value.AtomicValue
net.sf.saxon.value.NumericValue
All Implemented Interfaces:
Serializable, Comparable, PullEvent, SequenceIterable, GroundedValue, Item, ValueRepresentation, ConversionResult
Direct Known Subclasses:
DecimalValue, DoubleValue, FloatValue, IntegerValue
public abstract class NumericValue extends AtomicValue implements Comparable
NumericValue is an abstract superclass for IntegerValue, DecimalValue, FloatValue, and DoubleValue
See Also:

  • Constructor Details

    • NumericValue

      public NumericValue()

  • Method Details

    • parseNumber

      public static NumericValue parseNumber(String in)
      Get a numeric value by parsing a string; the type of numeric value depends on the lexical form of the string, following the rules for XPath numeric literals.
      Parameters:
      in - the input string
      Returns:
      a NumericValue representing the value of the string. Returns Double.NaN if the value cannot be parsed as a string.

    • getDoubleValue

      public double getDoubleValue()
      Get the numeric value as a double
      Returns:
      A double representing this numeric value; NaN if it cannot be converted

    • getFloatValue

      public float getFloatValue()
      Get the numeric value converted to a float
      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
      Returns:
      a decimal representing this numeric value;
      Throws:
      XPathException - if the value cannot be converted, for example if it is NaN or infinite

    • isInteger

      public static boolean isInteger(AtomicValue value)
      Test whether a value is an integer (an instance of a subtype of xs:integer)
      Parameters:
      value - the value being tested
      Returns:
      true if the value is an instance of xs:integer or a type derived therefrom

    • longValue

      public long longValue() throws XPathException
      Return the numeric value as a Java long.
      Returns:
      the numeric value as a Java long. This performs truncation towards zero.
      Throws:
      XPathException - if the value cannot be converted

    • negate

      public abstract NumericValue negate()
      Change the sign of the number
      Returns:
      a value, of the same type as the original, with its sign inverted

    • floor

      public abstract NumericValue floor()
      Implement the XPath floor() function
      Returns:
      a value, of the same type as that supplied, rounded towards minus infinity

    • ceiling

      public abstract NumericValue ceiling()
      Implement the XPath ceiling() function
      Returns:
      a value, of the same type as that supplied, rounded towards plus infinity

    • round

      public abstract NumericValue round()
      Implement the XPath round() function
      Returns:
      a value, of the same type as that supplied, rounded towards the nearest whole number (0.5 rounded up)

    • roundHalfToEven

      public abstract NumericValue roundHalfToEven(int scale)
      Implement the XPath 2.0 round-half-to-even() function
      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 abstract double signum()
      Determine whether the value is negative, zero, or positive
      Returns:
      -1 if negative, 0 if zero (including negative zero), +1 if positive, NaN if NaN

    • isWholeNumber

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

    • getXPathComparable

      public Object getXPathComparable(boolean ordered, StringCollator collator, XPathContext context)
      Get a Comparable value that implements the XPath ordering comparison semantics for this value. Returns null if the value is not comparable according to XPath rules. The default implementation returns null. This is overridden for types that allow ordered comparisons in XPath: numeric, boolean, string, date, time, dateTime, yearMonthDuration, dayTimeDuration, and anyURI.
      Specified by:
      getXPathComparable in class AtomicValue
      Parameters:
      ordered -
      collator -
      context -
      Returns:
      an Object whose equals() and hashCode() methods implement the XPath comparison semantics with respect to this atomic value. If ordered is specified, the result will either be null if no ordering is defined, or will be a Comparable

    • compareTo

      public int compareTo(Object other)
      Compare the value to another numeric value
      Specified by:
      compareTo in interface Comparable
      Parameters:
      other - The other numeric value
      Returns:
      -1 if this one is the lower, 0 if they are numerically equal, +1 if this one is the higher, or if either value is NaN. Where NaN values are involved, they should be handled by the caller before invoking this method.
      Throws:
      ClassCastException - if the other value is not a NumericValue (the parameter is declared as Object to satisfy the Comparable interface)

    • compareTo

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

    • equals

      public final boolean equals(Object other)
      The equals() function compares numeric equality among integers, decimals, floats, doubles, and their subtypes
      Specified by:
      equals in class AtomicValue
      Parameters:
      other - the value to be compared with this one
      Returns:
      true if the two values are numerically equal

    • promote

      public static ItemType promote(ItemType v1, ItemType v2, TypeHierarchy typeHierarchy)
      Identify lowest common supertype of two numeric values for promotion purposes
      Parameters:
      v1 - the item type of the first operand
      v2 - the item type of the second operand
      typeHierarchy - the type hierarchy cache
      Returns:
      the item type that should be used for arithmetic between operands of the two specified item types

    • hashCode

      public abstract int hashCode()
      hashCode() must be the same for two values that are equal. One way to ensure this is to convert the value to a double, and take the hashCode of the double. But this is expensive in the common case where we are comparing integers. So we adopt the rule: for values that are in the range of a Java Integer, we use the int value as the hashcode. For values outside that range, we convert to a double and take the hashCode of the double. This method needs to have a compatible implementation in each subclass.
      Overrides:
      hashCode in class Object
      Returns:
      the hash code of the numeric value

    • toString

      public String toString()
      Produce a string representation of the value
      Overrides:
      toString in class AtomicValue
      Returns:
      The result of casting the number to a string