net.sf.saxon.xpath

Class XPathFunctionLibrary

public class XPathFunctionLibrary extends 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
XPathFunctionLibrary()
Construct a XPathFunctionLibrary
Method Summary
Expressionbind(int nameCode, String uri, String local, Expression[] staticArgs)
Bind a function, given the URI and local parts of the function name, and the list of expressions supplied as arguments.
FunctionLibrarycopy()
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.
XPathFunctionResolvergetXPathFunctionResolver()
Get the resolver
booleanisAvailable(int fingerprint, String uri, String local, int arity)
Test whether an XPath function with a given name and arity is available.
voidsetXPathFunctionResolver(XPathFunctionResolver resolver)
Set the resolver

Constructor Detail

XPathFunctionLibrary

public XPathFunctionLibrary()
Construct a XPathFunctionLibrary

Method Detail

bind

public Expression bind(int nameCode, String uri, String local, Expression[] staticArgs)
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.

Parameters: nameCode The namepool code of the function name. This must match the supplied URI and local name. 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, arity, or signature.

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.

Returns: a copy of this function library. This must be an instance of the original class.

getXPathFunctionResolver

public XPathFunctionResolver getXPathFunctionResolver()
Get the resolver

Returns: the XPathFunctionResolver wrapped by this FunctionLibrary

isAvailable

public boolean isAvailable(int fingerprint, String uri, String local, int arity)
Test whether an XPath function with a given name and arity is available. This supports the function-available() function in XSLT. It is thus never used, and always returns false

Parameters: fingerprint The code that identifies the function name in the NamePool. This must match the supplied URI and local name. 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.

setXPathFunctionResolver

public void setXPathFunctionResolver(XPathFunctionResolver resolver)
Set the resolver

Parameters: resolver The XPathFunctionResolver wrapped by this FunctionLibrary