Class VendorFunctionLibrary

java.lang.Object
net.sf.saxon.functions.VendorFunctionLibrary
All Implemented Interfaces:
Serializable, FunctionLibrary

public class VendorFunctionLibrary extends Object implements FunctionLibrary
The VendorFunctionLibrary represents specially-recognized functions in the Saxon namespace. It doesn't handle Saxon extension functions that are implemented as normal extension functions, which are bound using the JavaExtensionLibrary.
See Also:
  • Constructor Details

    • VendorFunctionLibrary

      public VendorFunctionLibrary()
  • Method Details

    • register

      protected StandardFunction.Entry register(String name, Class implementationClass, int opcode, int minArguments, int maxArguments, ItemType itemType, int cardinality)
      Register an extension function in the table of function details.
      Parameters:
      name - the function name
      implementationClass - the class used to implement the function
      opcode - identifies the function when a single class implements several functions
      minArguments - the minimum number of arguments required
      maxArguments - the maximum number of arguments allowed
      itemType - the item type of the result of the function
      cardinality - the cardinality of the result of the function
      Returns:
      the entry describing the function. The entry is incomplete, it does not yet contain information about the function arguments.
    • init

      protected void init()
    • isAvailable

      public boolean isAvailable(int fingerprint, String uri, String local, int arity)
      Test whether a Saxon function with a given name and arity is available. This supports the function-available() function in XSLT. This method may be called either at compile time or at run time.
      Specified by:
      isAvailable in interface FunctionLibrary
      Parameters:
      fingerprint - The namepool fingerprint of the function name. This must match the uri and localName; the information is provided redundantly to avoid repeated lookups in the name pool.
      uri - The URI of the function name
      local - The local part of the function name
      arity - The number of arguments. This is set to -1 in the case of the single-argument function-available() function; in this case the method should return true if there is some matching extension function, regardless of its arity.
    • bind

      public Expression bind(int nameCode, String uri, String local, Expression[] staticArgs) throws XPathException
      Bind an extension 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:
      nameCode - The namepool nameCode of the function name. The uri and local name are also supplied (redundantly) to avoid fetching them from the name pool.
      uri - The URI of the function name
      local - The local part of the function name
      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.
      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 and arity.
      Throws:
      XPathException - if a function is found with the required name and arity, but the implementation of the function cannot be loaded or used; or if an error occurs while searching for the function; or if this function library "owns" the namespace containing the function call, but no function was found.
    • makeSaxonFunction

      public Expression makeSaxonFunction(String localName, StaticContext env, Expression[] arguments) throws XPathException
      Make a Saxon function with a given name
      Throws:
      XPathException
    • pluralArguments

      public static String pluralArguments(int num)
      Utility routine used in constructing error messages
    • 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.