Class NumberFn

    • Constructor Detail

      • NumberFn

        public NumberFn()
    • Method Detail

      • evaluateItem

        public Item evaluateItem​(XPathContext context)
                          throws XPathException
        Evaluate in a general context
        Specified by:
        evaluateItem in interface Expression
        Overrides:
        evaluateItem in class ComputedExpression
        Parameters:
        context - The context in which the expression is to be evaluated
        Returns:
        the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
        Throws:
        XPathException - if any dynamic error occurs evaluating the expression
      • convert

        public static DoubleValue convert​(AtomicValue value)
        Static method to perform the same conversion as the number() function. This is different from the convert(Type.DOUBLE) in that it produces NaN rather than an error for non-numeric operands.
      • map

        public Item map​(Item item)
                 throws XPathException
        Mapping function for use when converting a sequence of atomic values to doubles using the rules of the number() function
        Specified by:
        map in interface ItemMappingFunction
        Parameters:
        item - The input item to be mapped.
        Returns:
        either the output item, or null.
        Throws:
        XPathException