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Provides a basic XSLT 2.0 and XQuery 1.0 processor (W3C Recommendations,
January 2007). Command line interfaces and implementations of several
Java APIs (DOM, XPath, s9api) are also included.
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package net.sf.saxon.functions;
import net.sf.saxon.Err;
import net.sf.saxon.expr.Expression;
import net.sf.saxon.expr.StaticContext;
import net.sf.saxon.expr.StaticProperty;
import net.sf.saxon.om.NamespaceConstant;
import net.sf.saxon.om.StructuredQName;
import net.sf.saxon.pattern.NodeKindTest;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.type.BuiltInAtomicType;
import net.sf.saxon.type.ItemType;
import net.sf.saxon.type.Type;
import java.util.HashMap;
/**
* 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 {@link net.sf.saxon.functions.JavaExtensionLibrary}.
*/
public class VendorFunctionLibrary implements FunctionLibrary {
private HashMap functionTable;
/**
* Create the Vendor Function Library for Saxon
*/
public VendorFunctionLibrary() {
init();
}
/**
* Register an extension function in the table of function details.
* @param name the function name
* @param implementationClass the class used to implement the function
* @param opcode identifies the function when a single class implements several functions
* @param minArguments the minimum number of arguments required
* @param maxArguments the maximum number of arguments allowed
* @param itemType the item type of the result of the function
* @param cardinality the cardinality of the result of the function
* @return the entry describing the function. The entry is incomplete, it does not yet contain information
* about the function arguments.
*/
protected StandardFunction.Entry register( String name,
Class implementationClass,
int opcode,
int minArguments,
int maxArguments,
ItemType itemType,
int cardinality ) {
StandardFunction.Entry e = StandardFunction.makeEntry(
name, implementationClass, opcode, minArguments, maxArguments, itemType, cardinality);
functionTable.put(name, e);
return e;
}
protected void init() {
functionTable = new HashMap(30);
StandardFunction.Entry e;
e = register("evaluate", Evaluate.class, Evaluate.EVALUATE, 1, 10, Type.ITEM_TYPE, StaticProperty.ALLOWS_ZERO_OR_MORE);
StandardFunction.arg(e, 0, BuiltInAtomicType.STRING, StaticProperty.EXACTLY_ONE, null);
e = register("evaluate-node", Evaluate.class, Evaluate.EVALUATE_NODE, 1, 1, Type.ITEM_TYPE, StaticProperty.ALLOWS_ZERO_OR_MORE);
StandardFunction.arg(e, 0, Type.NODE_TYPE, StaticProperty.EXACTLY_ONE, null);
e = register("eval", Evaluate.class, Evaluate.EVAL, 1, 10, Type.ITEM_TYPE, StaticProperty.ALLOWS_ZERO_OR_MORE);
StandardFunction.arg(e, 0, BuiltInAtomicType.ANY_ATOMIC, StaticProperty.EXACTLY_ONE, null);
e = register("expression", Evaluate.class, Evaluate.EXPRESSION, 1, 1, BuiltInAtomicType.ANY_ATOMIC, StaticProperty.EXACTLY_ONE);
StandardFunction.arg(e, 0, BuiltInAtomicType.STRING, StaticProperty.EXACTLY_ONE, null);
e = register("is-whole-number", IsWholeNumber.class, 1, 1, 1, BuiltInAtomicType.BOOLEAN, StaticProperty.EXACTLY_ONE);
StandardFunction.arg(e, 0, BuiltInAtomicType.NUMERIC, StaticProperty.ALLOWS_ZERO_OR_ONE, null);
e = register("item-at", ItemAt.class, 1, 2, 2, StandardFunction.SAME_AS_FIRST_ARGUMENT, StaticProperty.ALLOWS_ZERO_OR_ONE);
StandardFunction.arg(e, 0, Type.ITEM_TYPE, StaticProperty.ALLOWS_ZERO_OR_MORE, null);
StandardFunction.arg(e, 1, BuiltInAtomicType.NUMERIC, StaticProperty.ALLOWS_ZERO_OR_ONE, null);
e = register("parse", Parse.class, 0, 1, 1, NodeKindTest.DOCUMENT, StaticProperty.EXACTLY_ONE);
StandardFunction.arg(e, 0, BuiltInAtomicType.STRING, StaticProperty.EXACTLY_ONE, null);
e = register("serialize", Serialize.class, 0, 2, 2, BuiltInAtomicType.STRING, StaticProperty.EXACTLY_ONE);
StandardFunction.arg(e, 0, Type.NODE_TYPE, StaticProperty.ALLOWS_ZERO_OR_ONE, null);
StandardFunction.arg(e, 1, Type.ITEM_TYPE, StaticProperty.EXACTLY_ONE, null);
}
/**
* 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.
* @param functionName the name of the function
* @param 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
*/
public boolean isAvailable(StructuredQName functionName, int arity) {
if (functionName.getNamespaceURI().equals(NamespaceConstant.SAXON)) {
StandardFunction.Entry entry = (StandardFunction.Entry)functionTable.get(functionName.getLocalName());
return entry != null && (arity == -1 ||
(arity >= entry.minArguments && arity <= entry.maxArguments));
} else {
return false;
}
}
/**
* 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.
* @param functionName the name of the function
* @param 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.
* @param env
* @return 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 net.sf.saxon.trans.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.
*/
public Expression bind(StructuredQName functionName, Expression[] staticArgs, StaticContext env)
throws XPathException {
String uri = functionName.getNamespaceURI();
String local = functionName.getLocalName();
if (uri.equals(NamespaceConstant.SAXON)) {
StandardFunction.Entry entry = (StandardFunction.Entry)functionTable.get(local);
if (entry == null) {
return null;
}
Class functionClass = entry.implementationClass;
SystemFunction f;
try {
f = (SystemFunction)functionClass.newInstance();
} catch (Exception err) {
throw new AssertionError("Failed to load Saxon extension function: " + err.getMessage());
}
f.setDetails(entry);
f.setFunctionName(functionName);
f.setArguments(staticArgs);
checkArgumentCount(staticArgs.length, entry.minArguments, entry.maxArguments, local);
return f;
} else {
return null;
}
}
/**
* Make a Saxon function with a given name
* @param localName the local name of the function
* @param env the static context
* @param arguments the arguments of the function
* @return an exprssion representing a call on the given function
*/
public Expression makeSaxonFunction(String localName, StaticContext env, Expression[] arguments)
throws XPathException {
String uri = NamespaceConstant.SAXON;
StructuredQName functionName = new StructuredQName("saxon", uri, localName);
return bind(functionName, arguments, env);
}
/**
* Check number of arguments.
* A convenience routine for use in subclasses.
* @param numArgs the actual number of arguments
* @param min the minimum number of arguments allowed
* @param max the maximum number of arguments allowed
* @param local the local name of the function, used for diagnostics
* @return the actual number of arguments
* @throws net.sf.saxon.trans.XPathException if the number of arguments is out of range
*/
private int checkArgumentCount(int numArgs, int min, int max, String local) throws XPathException {
if (min==max && numArgs != min) {
throw new XPathException("Function " + Err.wrap("saxon:"+local, Err.FUNCTION) + " must have "
+ min + pluralArguments(min));
}
if (numArgs < min) {
throw new XPathException("Function " + Err.wrap("saxon:"+local, Err.FUNCTION) + " must have at least "
+ min + pluralArguments(min));
}
if (numArgs > max) {
throw new XPathException("Function " + Err.wrap("saxon:"+local, Err.FUNCTION) + " must have no more than "
+ max + pluralArguments(max));
}
return numArgs;
}
/**
* Utility routine used in constructing error messages
* @param num a number
* @return the string " argument" or " arguments" if num is plural
*/
public static String pluralArguments(int num) {
if (num==1) return " argument";
return " arguments";
}
/**
* 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.
*
* @return a copy of this function library. This must be an instance of the original class.
*/
public FunctionLibrary copy() {
return this;
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (the "License");
// you may not use this file except in compliance with the License. You may obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
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