net.sf.saxon.style
Class StylesheetFunctionLibrary

java.lang.Object
  extended by net.sf.saxon.style.StylesheetFunctionLibrary
All Implemented Interfaces:
Serializable, FunctionLibrary

public class StylesheetFunctionLibrary
extends Object
implements FunctionLibrary

A StylesheetFunctionLibrary contains functions defined by the user in a stylesheet. This library is used at compile time only, as it contains references to the actual XSLFunction objects. Binding to a function in this library registers the function call on a fix-up list to be notified when the actual compiled function becomes available.

See Also:
Serialized Form

Constructor Summary
StylesheetFunctionLibrary(XSLStylesheet sheet, boolean overriding)
          Create a FunctionLibrary that provides access to stylesheet functions
 
Method Summary
 Expression bind(StructuredQName functionName, Expression[] staticArgs, StaticContext env)
          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.
 List getAllFunctions()
          Get a list of all functions in this StylesheetFunctionLibrary
 boolean isAvailable(StructuredQName functionName, int arity)
          Test whether a Saxon function with a given name and arity is available.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

StylesheetFunctionLibrary

public StylesheetFunctionLibrary(XSLStylesheet sheet,
                                 boolean overriding)
Create a FunctionLibrary that provides access to stylesheet functions

Parameters:
sheet - The XSLStylesheet element of the principal stylesheet module
overriding - set to true if this library is to contain functions specifying override="yes", or to false if it is to contain functions specifying override="no". (XSLT uses two instances of this class, one for overriding functions and one for non-overriding functions.)
Method Detail

isAvailable

public boolean isAvailable(StructuredQName functionName,
                           int arity)
Test whether a Saxon 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 -
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
Returns:
true if a function of this name and arity is available for calling.

bind

public Expression bind(StructuredQName functionName,
                       Expression[] staticArgs,
                       StaticContext env)
                throws XPathException
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 -
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.
env -
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.

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.

getAllFunctions

public List getAllFunctions()
Get a list of all functions in this StylesheetFunctionLibrary



Copyright (C) Michael H. Kay. All rights reserved.