Package net.sf.saxon.style

Class StylesheetFunctionLibrary

java.lang.Object

net.sf.saxon.style.StylesheetFunctionLibrary

All Implemented Interfaces:

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.

Constructor Summary

Constructors

Constructor	Description
StylesheetFunctionLibrary(StylesheetPackage sheet, boolean overrideExtensionFunction)	Create a FunctionLibrary that provides access to stylesheet functions

Method Summary

Modifier and Type	Method	Description
Expression	bind(SymbolicName.F functionName, Expression[] staticArgs, Map<StructuredQName,Integer> keywords, StaticContext env, List<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 functionName, 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.
StylesheetPackage	getStylesheetPackage()	Get the stylesheet package to which this function library relates
boolean	isAvailable(SymbolicName.F functionName, int languageLevel)	Test whether a function with a given name and arity is available
boolean	isOverrideExtensionFunction()	Ask whether the functions in this library are "overrideExtensionFunction" functions, that is, defined with xsl:function override="yes".

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.saxon.functions.FunctionLibrary

setConfiguration

Constructor Details

StylesheetFunctionLibrary

public StylesheetFunctionLibrary(StylesheetPackage sheet,
 boolean overrideExtensionFunction)

Create a FunctionLibrary that provides access to stylesheet functions

Parameters:

sheet - The XSLT package

overrideExtensionFunction - 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 overrideExtensionFunction functions and one for non-overrideExtensionFunction functions.)

Method Details

isOverrideExtensionFunction

public boolean isOverrideExtensionFunction()

Ask whether the functions in this library are "overrideExtensionFunction" functions, that is, defined with xsl:function override="yes".

Returns:

true if these are overrideExtensionFunction functions, false otherwise

getStylesheetPackage

public StylesheetPackage getStylesheetPackage()

Get the stylesheet package to which this function library relates

Returns:

the stylesheet package

bind

public Expression bind(SymbolicName.F functionName,
 Expression[] staticArgs,
 Map<StructuredQName,Integer> keywords,
 StaticContext env,
 List<String> reasons)
                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 - 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 - In the event that a function cannot be bound, this output parameter may be populated with one or more diagnostic messages indicating possible reasons why no function binding was possible.

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 matching function was identified, but the call is incorrect, for example because it uses incorrect argument keywords

getFunctionItem

public FunctionItem getFunctionItem(SymbolicName.F functionName,
 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:

functionName - 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.