/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2006 The eXist team
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
package org.exist.xquery.functions.fn;
import org.exist.dom.QName;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
import org.exist.xquery.ErrorCodes;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.AnyURIValue;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
import org.w3c.dom.Node;
/**
* xpath-library function: namespace-uri()
*
*/
public class FunNamespaceURI extends Function {
protected static final String FUNCTION_DESCRIPTION_0_PARAM =
"Returns the namespace URI of the xs:QName of the context item.\n\n";
protected static final String FUNCTION_DESCRIPTION_1_PARAM =
"Returns the namespace URI of the xs:QName of $arg.\n\n" +
"If the argument is omitted, it defaults to the context node (.). ";
protected static final String FUNCTION_DESCRIPTION_COMMON =
"The behavior of the function if the argument is omitted is exactly " +
"the same as if the context item had been passed as the argument.\n\n" +
"The following errors may be raised: if the context item is undefined " +
"[err:XPDY0002]XP; if the context item is not a node [err:XPTY0004]XP.\n\n" +
"If $arg is neither an element nor an attribute node, or if it is an " +
"element or attribute node whose expanded-QName (as determined by the " +
"dm:node-name accessor in the Section 5.11 node-name AccessorDM) is " +
"in no namespace, then the function returns the xs:anyURI " +
"corresponding to the zero-length string.";
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("namespace-uri", Function.BUILTIN_FUNCTION_NS),
FUNCTION_DESCRIPTION_0_PARAM + FUNCTION_DESCRIPTION_COMMON,
new SequenceType[0],
new FunctionReturnSequenceType(Type.ANY_URI, Cardinality.EXACTLY_ONE, "the namespace URI"),
false),
new FunctionSignature(
new QName("namespace-uri", Function.BUILTIN_FUNCTION_NS),
FUNCTION_DESCRIPTION_1_PARAM + FUNCTION_DESCRIPTION_COMMON,
new SequenceType[] {
new FunctionParameterSequenceType("arg", Type.NODE, Cardinality.ZERO_OR_ONE, "The input node")
},
new FunctionReturnSequenceType(Type.ANY_URI, Cardinality.EXACTLY_ONE, "the namespace URI"),
false)
};
public FunNamespaceURI(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES, "DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT SEQUENCE", contextSequence);}
if (contextItem != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT ITEM", contextItem.toSequence());}
}
Item item = null;
// check if the node is passed as an argument or should be taken from the context sequence
if(getArgumentCount() > 0) {
final Sequence seq = getArgument(0).eval(contextSequence, contextItem);
if(!seq.isEmpty())
{item = seq.itemAt(0);}
} else {
if (contextItem == null)
{throw new XPathException(this, ErrorCodes.XPDY0002, "Undefined context item");}
item = contextItem;
}
Sequence result;
if(item == null)
{result = AnyURIValue.EMPTY_URI;}
else {
if(!Type.subTypeOf(item.getType(), Type.NODE))
{throw new XPathException(this, ErrorCodes.XPTY0004, "Context item is not a node; got: " +
Type.getTypeName(item.getType()));}
//TODO : how to improve performance ?
final Node n = ((NodeValue)item).getNode();
result = new AnyURIValue(n.getNamespaceURI());
}
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
}