net.sf.saxon.functions
Class FunctionLibraryList
java.lang.Object
net.sf.saxon.functions.FunctionLibraryList
- FunctionLibrary, Serializable, FunctionLibrary, XQueryFunctionBinder
public class FunctionLibraryList
extends java.lang.Object
A FunctionLibraryList is a list of FunctionLibraries. It is also a FunctionLibrary in its own right.
When required, it searches the list of FunctionLibraries to find the required function.
libraryList
public List libraryList
addFunctionLibrary
public int addFunctionLibrary(FunctionLibrary lib)
Add a new FunctionLibrary to the list of FunctionLibraries in this FunctionLibraryList. Note
that libraries are searched in the order they are added to the list.
lib
- A function library to be added to the list of function libraries to be searched.
- the position of the library in the list
bind
public Expression bind(StructuredQName functionName,
Expression[] staticArgs,
StaticContext env)
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.
- bind in interface FunctionLibrary
functionName
- staticArgs
- The expressions supplied statically in arguments to the function call.
The length of this array represents the arity of the function. The intention is
that the static type of the arguments (obtainable via getItemType() and getCardinality() may
be used as part of the binding algorithm. In some cases it may be possible for the function
to be pre-evaluated at compile time, for example if these expressions are all constant values.env
-
- 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.
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.
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.
- copy in interface FunctionLibrary
- a copy of this function library. This must be an instance of the original class.
get
public FunctionLibrary get(int n)
Get the n'th function library in the list
getLibraryList
public List getLibraryList()
Get the list of contained FunctionLibraries. This method allows the caller to modify
the library list, for example by adding a new FunctionLibrary at a chosen position,
by removing a library from the list, or by changing the order of libraries in the list.
Note that such changes may violate rules in the
language specifications, or assumptions made within the product.
- a list whose members are of class FunctionLibrary
isAvailable
public boolean isAvailable(StructuredQName functionName,
int arity)
Test whether an extension 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.
- isAvailable in interface FunctionLibrary
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