Package net.sf.saxon.expr

Class Calculator

  • All Implemented Interfaces:
    java.io.Serializable
    public abstract class Calculator
extends java.lang.Object
implements java.io.Serializable
    This class evaluates arithmetic expressions; it acts as a helper class to the ArithmeticExpression class. There are many subclasses for the different kinds of arithmetic expression, and static methods that allow the right subclass to be selected, either at compile time or at run time.
    See Also:
    Serialized Form

    • Field Detail

      • ANY_ANY

        public static Calculator[] ANY_ANY
        Calculators used for the six operators when the static type information does not allow a more specific calculator to be chosen

      • DOUBLE_DOUBLE

        public static Calculator[] DOUBLE_DOUBLE
        Calculators used when the first operand is a double

      • DOUBLE_FLOAT

        public static Calculator[] DOUBLE_FLOAT

      • DOUBLE_DECIMAL

        public static Calculator[] DOUBLE_DECIMAL

      • DOUBLE_INTEGER

        public static Calculator[] DOUBLE_INTEGER

      • FLOAT_DOUBLE

        public static Calculator[] FLOAT_DOUBLE
        Calculators used when the first operand is a float

      • FLOAT_FLOAT

        public static Calculator[] FLOAT_FLOAT

      • FLOAT_DECIMAL

        public static Calculator[] FLOAT_DECIMAL

      • FLOAT_INTEGER

        public static Calculator[] FLOAT_INTEGER

      • DECIMAL_DOUBLE

        public static Calculator[] DECIMAL_DOUBLE
        Calculators used when the first operand is a decimal

      • DECIMAL_FLOAT

        public static Calculator[] DECIMAL_FLOAT

      • DECIMAL_DECIMAL

        public static Calculator[] DECIMAL_DECIMAL

      • DECIMAL_INTEGER

        public static Calculator[] DECIMAL_INTEGER

      • INTEGER_DOUBLE

        public static Calculator[] INTEGER_DOUBLE
        Calculators used when the first operand is an integer

      • INTEGER_FLOAT

        public static Calculator[] INTEGER_FLOAT

      • INTEGER_DECIMAL

        public static Calculator[] INTEGER_DECIMAL

      • INTEGER_INTEGER

        public static Calculator[] INTEGER_INTEGER

      • DATETIME_DATETIME

        public static Calculator[] DATETIME_DATETIME
        Calculators used when both operands are xs:dateTime, xs:date, or xs:time

      • DATETIME_DURATION

        public static Calculator[] DATETIME_DURATION
        Calculators used when the first operand is xs:dateTime, xs:date, or xs:time, and the second is a duration

      • DURATION_DATETIME

        public static Calculator[] DURATION_DATETIME
        Calculators used when the second operand is xs:dateTime, xs:date, or xs:time, and the first is a duration

      • DURATION_DURATION

        public static Calculator[] DURATION_DURATION
        Calculators used when the both operands are durations

      • DURATION_NUMERIC

        public static Calculator[] DURATION_NUMERIC
        Calculators used when the first operand is a duration and the second is numeric

      • NUMERIC_DURATION

        public static Calculator[] NUMERIC_DURATION
        Calculators used when the second operand is a duration and the first is numeric

    • Constructor Detail

      • Calculator

        public Calculator()

    • Method Detail

      • getCalculator

        public static Calculator getCalculator​(int typeA,
                                       int typeB,
                                       int operator,
                                       boolean mustResolve)
        Factory method to get a calculator for a given combination of types
        Parameters:
        typeA - fingerprint of the primitive type of the first operand
        typeB - fingerprint of the primitive type of the second operand
        operator - the arithmetic operator in use
        mustResolve - indicates that a concrete Calculator is required (rather than an ANY_ANY calculator which needs to be further resolved at run-time)
        Returns:
        null if no suitable Calculator can be found.

      • getCalculatorSetName

        public static java.lang.String getCalculatorSetName​(int typeA,
                                                    int typeB)
        Get the name of the calculator set for a given combination of types
        Parameters:
        typeA - the fingerprint of the primitive type of the first operand
        typeB - the fingerprint of the primitive type of the second operand
        Returns:
        null if no suitable Calculator can be found.

      • compute

        public abstract AtomicValue compute​(AtomicValue a,
                                    AtomicValue b,
                                    XPathContext c)
                             throws XPathException
        Perform an arithmetic operation
        Parameters:
        a - the first operand. Must not be null, and must be an instance of the type implied by the class name.
        b - the second operand. Must not be null, and must be an instance of the type implied by the class name.
        c - the XPath dynamic evaluation context
        Returns:
        the result of the computation, as a value of the correct primitive type
        Throws:
        XPathException - in the event of an arithmetic error

      • getResultType

        public abstract AtomicType getResultType​(AtomicType typeA,
                                         AtomicType typeB)
        Get the type of the result of the calculator, given arguments types typeA and typeB
        Parameters:
        typeA - the type of the first operand
        typeB - the type of the second operand
        Returns:
        the type of the result