Package net.sf.saxon.xpath

Class XPathFunctionLibrary

  • All Implemented Interfaces:
    FunctionLibrary
    public class XPathFunctionLibrary
extends java.lang.Object
implements FunctionLibrary
    The XPathFunctionLibrary is a FunctionLibrary that supports binding of XPath function calls to instances of the JAXP XPathFunction interface returned by an XPathFunctionResolver.

    • Constructor Summary

      Constructors 
      Constructor Description
      XPathFunctionLibrary()
      Construct a XPathFunctionLibrary

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Expression bind​(SymbolicName.F functionName, Expression[] staticArgs, java.util.Map<StructuredQName,​java.lang.Integer> keywords, StaticContext env, java.util.List<java.lang.String> reasons)
      Bind a function, given the URI and local parts of the function name, and the list of expressions supplied as arguments.
      FunctionLibrary copy()
      This method creates a copy of a FunctionLibrary: if the original FunctionLibrary allows new functions to be added, then additions to this copy will not affect the original, or vice versa.
      FunctionItem getFunctionItem​(SymbolicName.F symbolicName, StaticContext staticContext)
      Test whether a function with a given name and arity is available; if so, return a function item that can be dynamically called.
      javax.xml.xpath.XPathFunctionResolver getXPathFunctionResolver()
      Get the resolver
      boolean isAvailable​(SymbolicName.F functionName, int languageLevel)
      Test whether a function with a given name and arity is available
      void setXPathFunctionResolver​(javax.xml.xpath.XPathFunctionResolver resolver)
      Set the resolver

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • XPathFunctionLibrary

        public XPathFunctionLibrary()
        Construct a XPathFunctionLibrary

    • Method Detail

      • setXPathFunctionResolver

        public void setXPathFunctionResolver​(javax.xml.xpath.XPathFunctionResolver resolver)
        Set the resolver
        Parameters:
        resolver - The XPathFunctionResolver wrapped by this FunctionLibrary

      • getXPathFunctionResolver

        public javax.xml.xpath.XPathFunctionResolver getXPathFunctionResolver()
        Get the resolver
        Returns:
        the XPathFunctionResolver wrapped by this FunctionLibrary

      • bind

        public Expression bind​(SymbolicName.F functionName,
                       Expression[] staticArgs,
                       java.util.Map<StructuredQName,​java.lang.Integer> keywords,
                       StaticContext env,
                       java.util.List<java.lang.String> reasons)
        Bind a function, given the URI and local parts of the function name, and the list of expressions supplied as arguments. This method is called at compile time.
        Specified by:
        bind in interface FunctionLibrary
        Parameters:
        functionName - The name of the function
        staticArgs - The expressions supplied statically in the function call. The intention is that the static type of the arguments (obtainable via getItemType() and getCardinality() may be used as part of the binding algorithm.
        keywords - May be null if no keywords are used in the function call. Otherwise, a map identifying the keywords appearing in the function call, and the 0-based position at which they appeared.
        env - The static context
        reasons - If no matching function is found by the function library, it may add a diagnostic explanation to this list explaining why none of the available functions could be used.
        Returns:
        An object representing the extension function to be called, if one is found; null if no extension function was found matching the required name, arity, or signature.

      • getFunctionItem

        public FunctionItem getFunctionItem​(SymbolicName.F symbolicName,
                                    StaticContext staticContext)
                             throws XPathException
        Test whether a function with a given name and arity is available; if so, return a function item that can be dynamically called.

        This supports the function-lookup() function in XPath 3.0.

        Specified by:
        getFunctionItem in interface FunctionLibrary
        Parameters:
        symbolicName - the qualified name of the function being called
        staticContext - the static context to be used by the function, in the event that it is a system function with dependencies on the static context
        Returns:
        if a function of this name and arity is available for calling, then a corresponding function item; or null if the function does not exist
        Throws:
        XPathException - in the event of certain errors, for example attempting to get a function that is private

      • isAvailable

        public boolean isAvailable​(SymbolicName.F functionName,
                           int languageLevel)
        Test whether a function with a given name and arity is available

        This supports the function-available() function in XSLT.

        Specified by:
        isAvailable in interface FunctionLibrary
        Parameters:
        functionName - the qualified name of the function being called
        languageLevel - the XPath language level (times 10, e.g. 31 for XPath 3.1)
        Returns:
        true if a function of this name and arity is available for calling

      • copy

        public FunctionLibrary copy()
        This method creates a copy of a FunctionLibrary: if the original FunctionLibrary allows new functions to be added, then additions to this copy will not affect the original, or vice versa.
        Specified by:
        copy in interface FunctionLibrary
        Returns:
        a copy of this function library. This must be an instance of the original class.