Class FunctionArity

All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, CallableExpression, InstructionInfo, Locator

public class FunctionArity extends SystemFunction implements CallableExpression
This class implements the function function-arity(), which is a standard function in XQuery 1.1
See Also:
  • Constructor Details

    • FunctionArity

      public FunctionArity()
  • Method Details

    • getIntegerBounds

      public IntegerValue[] getIntegerBounds()
      For an expression that returns an integer or a sequence of integers, get a lower and upper bound on the values of the integers that may be returned, from static analysis. The default implementation returns null, meaning "unknown" or "not applicable". Other implementations return an array of two IntegerValue objects, representing the lower and upper bounds respectively. The values UNBOUNDED_LOWER and UNBOUNDED_UPPER are used by convention to indicate that the value may be arbitrarily large. The values MAX_STRING_LENGTH and MAX_SEQUENCE_LENGTH are used to indicate values limited by the size of a string or the size of a sequence.
      Overrides:
      getIntegerBounds in class Expression
      Returns:
      the lower and upper bounds of integer values in the result, or null to indicate unknown or not applicable.
    • evaluateItem

      public Item evaluateItem(XPathContext context) throws XPathException
      Evaluate this function call at run-time
      Overrides:
      evaluateItem in class Expression
      Parameters:
      context - The XPath dynamic evaluation context
      Returns:
      the result of the function, or null to represent an empty sequence
      Throws:
      XPathException - if a dynamic error occurs during evaluation of the function.
    • call

      public SequenceIterator call(SequenceIterator[] arguments, XPathContext context) throws XPathException
      Evaluate the expression
      Specified by:
      call in interface CallableExpression
      Parameters:
      arguments - the values of the arguments, supplied as SequenceIterators
      context - the dynamic evaluation context
      Returns:
      the result of the evaluation, in the form of a SequenceIterator
      Throws:
      XPathException - if a dynamic error occurs during the evaluation of the expression