Class SimplePathInterpreter


  • public class SimplePathInterpreter
    extends java.lang.Object
    An evaluation mechanism for simple XPaths, which is much faster than the usual process. It is only used for xpaths which have no context-dependent parts, consist entirely of child::name and self::node() steps with predicates that either integer or have the form [@name = ...].
    Version:
    $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
    Author:
    Dmitri Plotnikov
    • Constructor Detail

      • SimplePathInterpreter

        public SimplePathInterpreter()
    • Method Detail

      • interpretSimpleLocationPath

        public static NodePointer interpretSimpleLocationPath​(EvalContext context,
                                                              NodePointer root,
                                                              Step[] steps)
        Interpret a simple path that starts with the given root and follows the given steps. All steps must have the axis "child::" and a name test. They can also optionally have predicates of type [@name=expression] or simply [expression] interpreted as an index.
        Parameters:
        context - evaluation context
        root - root pointer
        steps - path steps
        Returns:
        NodePointer
      • interpretSimpleExpressionPath

        public static NodePointer interpretSimpleExpressionPath​(EvalContext context,
                                                                NodePointer root,
                                                                Expression[] predicates,
                                                                Step[] steps)
        Interpret the steps of a simple expression path that starts with the given root, which is the result of evaluation of the root expression of the expression path, applies the given predicates to it and then follows the given steps. All steps must have the axis "child::" or "attribute::" and a name test. They can also optionally have predicates of type [@name=...] or simply [...] interpreted as an index.
        Parameters:
        context - evaluation context
        root - root pointer
        predicates - predicates corresponding to steps
        steps - path steps
        Returns:
        NodePointer
      • createNullPointer

        public static NodePointer createNullPointer​(EvalContext context,
                                                    NodePointer parent,
                                                    Step[] steps,
                                                    int currentStep)
        Creates a "null pointer" that a) represents the requested path and b) can be used for creation of missing nodes in the path.
        Parameters:
        context - evaluation context
        parent - parent pointer
        steps - path steps
        currentStep - step number
        Returns:
        NodePointer