Class FormatNumber

    • Constructor Detail

      • FormatNumber

        public FormatNumber()
    • Method Detail

      • fixArguments

        public Expression fixArguments​(Expression... arguments)
                                throws XPathException
        Allow the function to create an optimized call based on the values of the actual arguments. This handles the case where the decimal format name is supplied as a literal (or defaulted), and the picture string is also supplied as a literal.
        fixArguments in class SystemFunction
        arguments - the supplied arguments to the function call
        either a function call on this function, or an expression that delivers the same result, or null indicating that no optimization has taken place
        XPathException - if an error is detected
      • adjustToDecimal

        public static java.math.BigDecimal adjustToDecimal​(double value,
                                                           int precision)
        Convert a double to a BigDecimal. In general there will be several BigDecimal values that are equal to the supplied value, and the one we want to choose is the one with fewest non-zero digits. The algorithm used is rather pragmatic: look for a string of zeroes or nines, try rounding the number down or up as appropriate, then convert the adjusted value to a double to see if it's equal to the original: if not, use the original value unchanged.
        value - the double to be converted
        precision - 2 for a double, 1 for a float
        the result of conversion to a double
      • call

        public StringValue call​(XPathContext context,
                                Sequence[] arguments)
                         throws XPathException
        Call the format-number function, supplying two or three arguments
        Specified by:
        call in interface Callable
        context - the dynamic evaluation context
        arguments - the values of the arguments, supplied as Sequences.

        Generally it is advisable, if calling iterate() to process a supplied sequence, to call it only once; if the value is required more than once, it should first be converted to a GroundedValue by calling the utility methd SequenceTool.toGroundedValue().

        If the expected value is a single item, the item should be obtained by calling Sequence.head(): it cannot be assumed that the item will be passed as an instance of Item or AtomicValue.

        It is the caller's responsibility to perform any type conversions required to convert arguments to the type expected by the callee. An exception is where this Callable is explicitly an argument-converting wrapper around the original Callable.

        the result of the function
        XPathException - if any dynamic error occurs
      • getNamedDecimalFormat

        protected DecimalSymbols getNamedDecimalFormat​(DecimalFormatManager dfm,
                                                       java.lang.String lexicalName)
                                                throws XPathException
        Get a decimal format, given its lexical QName
        dfm - the decimal format manager
        lexicalName - the lexical QName (or EQName) of the decimal format
        the decimal format
        XPathException - if the lexical QName is invalid or if no decimal format is found.
      • formatExponential

        public static java.lang.String formatExponential​(DoubleValue value)
        Format a double as required by the adaptive serialization method
        value - the value to be formatted
        the formatted value
      • copy

        public FormatNumber copy()
        Make a copy of this SystemFunction. This is required only for system functions such as regex functions that maintain state on behalf of a particular caller.
        Specified by:
        copy in interface StatefulSystemFunction
        a copy of the system function able to contain its own copy of the state on behalf of the caller.
      • getFormatter

        public static java.util.function.Function<java.lang.Double,​java.lang.String> getFormatter​(java.lang.String picture)
                                                                                                 throws XPathException
        Get a function to format a double as a string using a supplied picture
        picture - the supplied picture
        a function that converts a double to a string
        XPathException - if the picture is invalid