Class StringFn

All Implemented Interfaces:
Serializable, SourceLocator, LocationProvider, SaxonLocator, EvaluableItem, SequenceIterable, InstructionInfo, Locator

public class StringFn extends SystemFunction
Implement XPath function string()
See Also:
  • Constructor Details

    • StringFn

      public StringFn()
  • Method Details

    • simplify

      public Expression simplify(ExpressionVisitor visitor) throws XPathException
      Simplify and validate. This is a pure function so it can be simplified in advance if the arguments are known
      Overrides:
      simplify in class FunctionCall
      Parameters:
      visitor - an expression visitor
      Returns:
      the simplified expression
      Throws:
      XPathException - if an error is discovered during expression rewriting
    • addDocToPathMap

      public PathMap.PathMapNodeSet addDocToPathMap(PathMap pathMap, PathMap.PathMapNodeSet pathMapNodes)
      Add a representation of a doc() call or similar function to a PathMap. This is a convenience method called by the addToPathMap() methods for doc(), document(), collection() and similar functions. These all create a new root expression in the path map.
      Overrides:
      addDocToPathMap in class SystemFunction
      Parameters:
      pathMap - the PathMap to which the expression should be added
      pathMapNodes - the node in the PathMap representing the focus at the point where this expression is called. Set to null if this expression appears at the top level.
      Returns:
      the pathMapNode representing the focus established by this expression, in the case where this expression is the first operand of a path expression or filter expression
    • evaluateItem

      public Item evaluateItem(XPathContext c) throws XPathException
      Evaluate the function
      Specified by:
      evaluateItem in interface EvaluableItem
      Overrides:
      evaluateItem in class Expression
      Parameters:
      c - 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