/* * eXist Open Source Native XML Database * Copyright (C) 2001-09 Wolfgang M. Meier * wolfgang@exist-db.org * http://exist-db.org * * 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., 675 Mass Ave, Cambridge, MA 02139, USA. * * $Id$ */ package org.exist.xquery.functions; import org.exist.dom.QName; import org.exist.dom.QNameable; 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.QNameValue; import org.exist.xquery.value.Sequence; import org.exist.xquery.value.SequenceType; import org.exist.xquery.value.Type; import org.w3c.dom.Node; /** * Implements the fn:node-name library function. * * @author wolf */ public class FunNodeName extends Function { public final static FunctionSignature signature = new FunctionSignature( new QName("node-name", Function.BUILTIN_FUNCTION_NS), "Returns an expanded-QName for node kinds that can have names. For other kinds " + "of nodes it returns the empty sequence. If $arg is the empty sequence, the " + "empty sequence is returned.", new SequenceType[] { new FunctionParameterSequenceType("arg", Type.NODE, Cardinality.ZERO_OR_ONE, "The input node") }, new FunctionReturnSequenceType(Type.QNAME, Cardinality.ZERO_OR_ONE, "the expanded QName")); /** * @param context */ public FunNodeName(XQueryContext context) { 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()); } Sequence result; Sequence seq = getArgument(0).eval(contextSequence, contextItem); if(seq.isEmpty()) result = Sequence.EMPTY_SEQUENCE; else { Item item = seq.itemAt(0); 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(); //Returns an expanded-QName for node kinds that can have names. if (n instanceof QNameable) { QName qn= ((QNameable)n).getQName(); if (qn.equalsSimple(QName.EMPTY_QNAME)) result = Sequence.EMPTY_SEQUENCE; else result = new QNameValue(context, qn); //For other kinds of nodes it returns the empty sequence. } else result = Sequence.EMPTY_SEQUENCE; } if (context.getProfiler().isEnabled()) context.getProfiler().end(this, "", result); return result; } }