/* eXist Open Source Native XML Database
* Copyright (C) 2000-2009, 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;
import org.exist.dom.QName;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
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.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.StringValue;
import org.exist.xquery.value.Type;
import org.w3c.dom.Node;
/**
* Built-in function fn:local-name().
*
*/
public class FunLocalName extends Function {
protected static final String FUNCTION_DESCRIPTION =
"Returns the local part of the name of $arg as an xs:string that " +
"will either be the zero-length string or will have the lexical form of an xs:NCName.\n\n" +
"If the argument is omitted, it defaults to the context item (.). " +
"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 the argument is supplied and is the empty sequence, the function " +
"returns the zero-length string.\n\n" +
"If the target node has no name (that is, if it is a document node, a " +
"comment, or a text node), the function returns the zero-length string.\n\n" +
"Otherwise, the value returned will be the local part of the expanded-QName " +
"of the target node (as determined by the dm:node-name accessor in Section " +
"5.11 node-name AccessorDM. This will be an xs:string whose lexical form is an xs:NCName." ;
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName("local-name", Function.BUILTIN_FUNCTION_NS),
FUNCTION_DESCRIPTION,
new SequenceType[0],
new FunctionReturnSequenceType(Type.STRING, Cardinality.EXACTLY_ONE, "the local name")
),
new FunctionSignature(
new QName("local-name", Function.BUILTIN_FUNCTION_NS),
FUNCTION_DESCRIPTION,
new SequenceType[] { new FunctionParameterSequenceType("arg", Type.NODE, Cardinality.ZERO_OR_ONE, "The node to retrieve the local name from") },
new FunctionReturnSequenceType(Type.STRING, Cardinality.EXACTLY_ONE, "the local name")
)
};
public FunLocalName(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());
}
if(contextItem != null)
contextSequence = 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) {
Sequence seq = getArgument(0).eval(contextSequence);
if (!seq.isEmpty())
item = seq.itemAt(0);
} else {
if (contextSequence == null || contextSequence.isEmpty())
throw new XPathException(this, "XPDY0002: Undefined context item");
item = contextSequence.itemAt(0);
}
Sequence result;
if (item == null)
result = StringValue.EMPTY_STRING;
else {
if (!Type.subTypeOf(item.getType(), Type.NODE))
throw new XPathException(this, "XPTY0004: item is not a node; got '" + Type.getTypeName(item.getType()) + "'");
//TODO : how to improve performance ?
Node n = ((NodeValue)item).getNode();
result = new StringValue(n.getLocalName());
}
if (context.getProfiler().isEnabled())
context.getProfiler().end(this, "", result);
return result;
}
}