Class ArithmeticExpression

All Implemented Interfaces:
Serializable, SourceLocator, Container, Expression, InstructionInfoProvider
Direct Known Subclasses:
ArithmeticExpression.DateAndDuration, ArithmeticExpression.DateDifference, ArithmeticExpression.DurationAddition, ArithmeticExpression.DurationDivision, ArithmeticExpression.DurationMultiplication, ArithmeticExpression.NumericArithmetic

public class ArithmeticExpression extends BinaryExpression
Arithmetic Expression: an expression using one of the operators plus, minus, multiply, div, idiv, mod.
See Also:
  • Constructor Details

  • Method Details

    • typeCheck

      public Expression typeCheck(StaticContext env, ItemType contextItemType) throws XPathException
      Type-check the expression statically. We try to work out which particular arithmetic function to use if the types of operands are known an compile time.
      Specified by:
      typeCheck in interface Expression
      Overrides:
      typeCheck in class BinaryExpression
      Parameters:
      env - the static context of the expression
      contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
      Returns:
      the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
      Throws:
      XPathException
    • getItemType

      public ItemType getItemType(TypeHierarchy th)
      Determine the data type of the expression, if this is known statically
      Parameters:
      th -
      Returns:
      a value such as Type.STRING, Type.BOOLEAN, Type.NUMBER, Type.NODE, or Type.ITEM (meaning not known at compile time)
    • evaluateItem

      public Item evaluateItem(XPathContext context) throws XPathException
      Evaluate the expression. We only take this path if the type could not be determined statically.
      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