/*
* eXist Open Source Native XML Database
* Copyright (C) 2010 The eXist Project
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
package org.exist.xquery.modules.sort;
import org.exist.EXistException;
import org.exist.dom.QName;
import org.exist.indexing.sort.SortIndex;
import org.exist.indexing.sort.SortIndexWorker;
import org.exist.util.LockException;
import org.exist.xquery.*;
import org.exist.xquery.value.*;
public class HasIndex extends BasicFunction {
public final static FunctionSignature signature =
new FunctionSignature(
new QName("has-index", SortModule.NAMESPACE_URI, SortModule.PREFIX),
"Check if the sort index, $id, exists.",
new SequenceType[] {
new FunctionParameterSequenceType("id", Type.STRING, Cardinality.EXACTLY_ONE, "The name of the index.")
},
new FunctionReturnSequenceType(Type.BOOLEAN, Cardinality.EXACTLY_ONE, "true() if the sort index, $id, exists, false() otherwise."));
public HasIndex(XQueryContext context) {
super(context, signature);
}
@Override
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
String id = args[0].getStringValue();
SortIndexWorker index = (SortIndexWorker)
context.getBroker().getIndexController().getWorkerByIndexId(SortIndex.ID);
try {
return BooleanValue.valueOf(index.hasIndex(id));
} catch (EXistException e) {
throw new XPathException(this, e.getMessage(), e);
} catch (LockException e) {
throw new XPathException(this, "Caught lock error while searching index. Giving up.", e);
}
}
}